The path toward a renewable energy future relies on the development of materials for electrochemical energy technologies that are not only highly functional but also stable. In this Perspective, we will discuss a framework for the relationships between function and stability, starting by revisiting how we measure stability that should focus on changes to the nature and number of active centers (materials stability) together with monitoring how current/potential change over time during operation (reaction durability). By shifting our focus to materials properties, we then discuss how subtractive and additive processes such as dissolution, deposition, and (de)intercalation contribute to changes in the local surface composition, coordination environment, and phase restructuring that accompany the degradation of electrochemical materials. Ultimately, gaining insights into the processes responsible for changes to active centers during operation will help us better predict and control the durability of materials for clean energy.

Understanding the interaction between biomaterials and blood is critical in the design of novel biomaterials for use in biomedical applications. Depending on the application, biomaterials can be designed to promote hemostasis, slow or stop bleeding in an internal or external wound, or prevent thrombosis for use in permanent or temporary medical implants. Bacterial nanocellulose (BNC) is a natural, biocompatible biopolymer that has recently gained interest for its potential use in blood-contacting biomedical applications (e.g., artificial vascular grafts), due to its high porosity, shapeability, and tissue-like properties. To promote hemostasis, BNC has been modified through oxidation or functionalization with various peptides, proteins, polysaccharides, and minerals that interact with the coagulation cascade. For use as an artificial vascular graft or to promote vascularization, BNC has been extensively researched, with studies investigating different modification techniques to enhance endothelialization such as functionalizing with adhesion peptides or extracellular matrix (ECM) proteins as well as tuning the structural properties of BNC such as surface roughness, pore size, and fiber size. While BNC inherently exhibits comparable mechanical characteristics to endogenous blood vessels, these mechanical properties can be enhanced through chemical functionalization or through altering the fabrication method. In this review, we provide a comprehensive overview of the various modification techniques that have been implemented to enhance the suitability of BNC for blood-contacting biomedical applications and different testing techniques that can be applied to evaluate their performance. Initially, we focused on the modification techniques that have been applied to BNC for hemostatic applications. Subsequently, we outline the different methods used for the production of BNC-based artificial vascular grafts and to generate vasculature in tissue engineered constructs. This sequential organization enables a clear and concise discussion of the various modifications of BNC for different blood-contacting biomedical applications and highlights the diverse and versatile nature of BNC as a natural biomaterial.

We are issuing a correction to a typo in eq 6 on page 95. In the text, we describe the surface-catalyzed decomposition of the electrolyte salt that produces the same products as LiPF6 hydrolysis. We propose a reaction between acidic hydroxyl groups on the active particles and LiPF6 (not PF5), and thus eq 6 should appear as follows: To further elaborate, the overall reaction shown in eq 6 is reached via Mnsurface–OH catalyzed decomposition of LiPF6 as follows: The statement that introduces the proposed surface-catalyzed decomposition of LiPF6 should state, “...supporting that PF6– decomposition reactions (eqs 6 and 7) proceed via an alternative proton source...” The data interpretation and the conclusions remain unchanged. This article has not yet been cited by other publications.

Partial cation exchange reactions provide a synthetic pathway for rationally constructing heterostructured nanoparticles that incorporate different materials at precise locations. Multiple sequential partial cation exchange reactions can produce libraries of exceptionally complex heterostructured nanoparticles, but the first partial exchange reaction is responsible for defining the intraparticle frameworks that persist throughout and help to direct subsequent exchanges. Here, we studied the partial cation exchange behavior of spherical nanoparticles of roxbyite copper sulfide, Cu1.8S, with substoichiometric amounts of Zn2+. We observed the formation of ZnS–Cu1.8S–ZnS sandwich spheres, which are already well known in this system, as well as ZnS–Cu1.8S Janus spheres and Cu1.8S–ZnS–Cu1.8S central band spheres, which have not been observed previously as significant subpopulations of samples. Aliquots taken during the formation of the heterostructured nanoparticles suggest that substoichiometric amounts of Zn2+ limit the number of sites per particle where exchange initiates and/or propagates, thereby helping to define intraparticle frameworks that are different from those observed using excess amounts of exchanging cations. We applied these insights from mixed-population samples to the higher-yield synthesis of ZnS–Cu1.8S Janus spheres, as well as the higher-order derivatives ZnS–(CdS–Cu1.8S), ZnS–(CdS–ZnS), and ZnS–(CdS–CoS), which have unique features relative to previously reported analogues. These results demonstrate how the diversity of intraparticle frameworks in spherical nanoparticles can be expanded to produce a broader range of downstream heterostructured products.

Close collaboration between basic researchers and clinicians is at the root of medical material and technology innovation. However, the distinctly different educational curricula and various boundary conditions put barriers on such interactions. This short perspective describes current challenges and provides subsequent solutions that may help research laboratories to overcome frequent hurdles and maximize interdisciplinary interactions. The involvement of various stakeholders is key to establishing an environment for barrier-free, effective collaboration, overcoming disciplinary boundaries and creating a strong source of inspiration and motivation for biomedical innovations with clinical impact.

Cancer is a major healthcare burden and cause of death worldwide, with an estimated 19.3 million new cancer cases and 10 million cancer deaths globally only in 2020. While several anticancer therapeutics are available to date, many of these still show low treatment efficacy and high off-target effects and adverse reactions. This prompts a serious need to develop novel therapies that can decrease the side effects and increase treatment efficacy. MicroRNAs (miRNAs) can have a role in tumor development and progression, making them important targets for the improvement of anticancer therapies. In this context, gold nanoparticles have been widely studied for different clinical applications due to their biocompatibility and possibility of customization, and gold nanoconjugates targeting miRNAs are being developed for cancer diagnosis and treatment. Here we summarize the research developed so far and how it can contribute to cancer treatment, discuss how it can be improved, and present the current challenges and future perspectives on their design and application.

Over the past several years, significant advances have been made in the development of high-surface-area porous cages. Despite this, relatively little work has been done to explore their use for the storage of hydrogen and other gases. To address this knowledge gap, we explored hydrogen storage across 20 porous cages of a variety of structure types. Trends across various structure types are discussed in some detail, with adsorption sites for a subset of the materials contextualized using powder neutron diffraction data for structurally related metal–organic framework (MOF) pores. Of the studied materials, the carbazole-based octahedral cages, M12(cdc)12 (M = Cr2+, Mo2+; cdc2– = carbazole-dicarboxylic acid), performed the best, with a 1 bar, 77 K hydrogen uptake of 9.26 mmol/g (13.9 g/L) for M = Cr2+.

We report a series of adamantane-functionalized azobenzenes that store photon and thermal energy via reversible photoisomerization in the solid state for molecular solar thermal (MOST) energy storage. The adamantane unit serves as a 3D molecular separator that enables the spatial separation of azobenzene groups and results in their facile switching even in the crystalline phase. Upon isomerization, the phase transition from crystalline to amorphous solid occurs and contributes to additional energy storage. The exclusively solid-state MOST compounds with solid–solid phase transition overcome a major challenge of solid–liquid phase transition materials that require encapsulation for practical applications.

In this work, we developed an atomic layer deposition (ALD) process for gold metal thin films from chloro(triethylphosphine)gold(I) [AuCl(PEt3)] and 1,4-bis(trimethylgermyl)-1,4-dihydropyrazine [(Me3Ge)2DHP]. High purity gold films were deposited on different substrate materials at 180 °C for the first time with thermal reductive ALD. The growth rate is 1.7 Å/cycle after the film reaches full coverage. The films have a very low resistivity close to the bulk value, and a minimal amount of impurities could be detected. The reaction mechanism of the process is studied in situ with a quartz crystal microbalance and a quadrupole mass spectrometer.

Molecular systems composed of information-rich nucleic acids have emerged as one of the most robust materials due to their programmability, editability, and designability. Among their various applications, the specific and sensitive in vitro detection of biomolecules for the purpose of disease diagnosis has attracted increasing attention from both fundamental and translational researchers. In this perspective, we introduce the basic design principles for nucleic acid molecular systems toward in vitro detection of biomolecules, accompanied by representative examples from reported works. The perspective concludes with perspectives and outlooks to tackle a variety of technical hurdles for the development and practical translation of nucleic acid molecular systems for biomolecule detection.

Due to the contamination and global warming problems, it is necessary to search for alternative environmentally friendly energy sources. In this area, hydrogen is a promising alternative. Hydrogen is even more promising, when it is obtained through water electrolysis operated with renewable energy sources. Among the possible devices to perform electrolysis, proton exchange membrane (PEM) electrolyzers appear as the most promising commercial systems for hydrogen production in the coming years. However, their massification is affected by the noble metals used as electrocatalysts in their electrodes, with high commercial value: Pt at the cathode where the hydrogen evolution reaction occurs (HER) and Ru/Ir at the anode where the oxygen evolution reaction (OER) happens. Therefore, to take full advantage of the PEM technology for green H2 production and build up a mature PEM market, it is imperative to search for more abundant, cheaper, and stable catalysts, reaching the highest possible activities at the lowest overpotential with the longest stability under the harsh acidic conditions of a PEM. In the search for new electrocatalysts and considering the predictions of a Trasatti volcano plot, rhenium appears to be a promising candidate for HER in acidic media. At the same time, recent studies provide evidence of its potential as an OER catalyst. However, some of these reports have focused on chemical and photochemical water splitting and have not always considered acidic media. This review summarizes rhenium-based electrocatalysts for water splitting under acidic conditions: i.e., potential candidates as cathode materials. In the various sections, we review the mechanism concepts of electrocatalysis, evaluation methods, and the different rhenium-based materials applied for the HER in acidic media. As rhenium is less common for the OER, we included a section about its use in chemical and photochemical water oxidation and as an electrocatalyst under basic conditions. Finally, concluding remarks and perspectives are given about rhenium for water splitting.

The long-unresolved issue of CO2 release and the resulting atmospheric change can be solved through the application of effective catalysts. Thus, single-atom catalysts (SACs) have been rapidly developed for the CO2 reduction reaction (CO2RR), as they show improved catalytic metrics and enable the generation of C2+ products. Among numerous novel SACs, such as those based on graphene, metal–organic frameworks, and covalent organic frameworks (COFs), the COF-based SACs are the most promising owing to their high stability, porosity, and designability. Considering this, we describe two synthesis methods of COF-based SACs: ligand coordination and macrocycle backbone integration, and explore the pros and cons of each. We also propose routes for designing superior COF-based SACs and evaluate the factors influencing CO2RRs over COF-based SACs, such as metal loading and ligand types.

The thiospinel group of nickel cobalt sulfides (NixCo3–xS4) are promising materials for energy applications such as supercapacitors, fuel cells, and solar cells. Solution-processible nanoparticles of NixCo3–xS4 have advantages of low cost and fabrication of high-performance energy devices due to their high surface-to-volume ratio, which increases the electrochemically active surface area and shortens the ionic diffusion path. The current approaches to synthesize NixCo3–xS4 nanoparticles are often based on hydrothermal or solvothermal methods that are difficult to scale up safely and efficiently and that preclude monitoring the reaction through aliquots, making optimization of size and dispersity challenging, typically resulting in aggregated nanoparticles with polydisperse sizes. In this work, we report a scalable “heat-up” method to colloidally synthesize NixCo3–xS4 nanoparticles that are smaller than 15 nm in diameter with less than 15% in size dispersion, using two inexpensive, earth-abundant sulfur sources. Our method provides a reliable synthetic pathway to produce phase-pure, low-dispersity, gram-scale nanoparticles of ternary metal sulfides. This method enhances the current capabilities of NixCo3–xS4 nanoparticles to meet the performance demands to improve renewable energy technologies.

For indoor light harvesting, the adjustable band gap of molecular semiconductors is a significant advantage relative to many inorganic photovoltaic technologies. However, several challenges have to be overcome that include processability in nonhalogenated solvents, sufficiently high thicknesses (>250 nm) and high efficiencies at illuminances typically found in indoor environments. Here, we report on the development and application of new methods to quantify and identify performance losses based on thickness- and intensity-dependent current density–voltage measurements. Furthermore, we report on the fabrication of solar cells based on the blend PBDB-T:F-M processed in the nonhalogenated solvent o-xylene. In the low-intensity regime, insufficiently high shunt resistances limit the photovoltaic performance and by analyzing current density voltage–curves for solar cells with various shunt resistances we find that ∼100 kΩ cm2 are required at 200 lux. We provide a unified description of fill factor losses introducing the concept of light-intensity-dependent apparent shunts that originate from incomplete and voltage-dependent charge collection. In experiment and simulation, we show that good fill factors are associated with a photo-shunt inversely scaling with intensity. Intensity regions with photo-shunt resistances close to the dark-shunt resistance are accompanied by severe extraction losses. To better analyze recombination, we perform a careful analysis of the light intensity and thickness dependence of the open-circuit voltage and prove that trap-assisted recombination dominates the recombination losses at low light intensities.

Donor-doped melilite materials with interstitial oxygen defects in the structure are good oxide ion conductors with negligible electronic conduction and show great potential in the ceramic electrolyte of intermediate-temperature solid oxide fuel cells (IT-SOFC). However, the parent melilite-structured materials with stoichiometric oxygen are usually insulators. Herein, we reported high and pure oxide ion conduction in the parent K2ZnV2O7 material with a melilite-related structure, e.g., ∼1.14 × 10–3 S/cm at 600 °C, which is comparable to that of the state-of-the-art yttrial-stabilized ZrO2 applied in practical fuel cells. Neutron diffraction data revealed the interesting thermally induced formation of oxygen vacancies at elevated temperatures, which triggered the transformation of the material from electronically conducting to purely and highly oxide ion-conducting. The VO4 tetrahedron with non-bridging terminal oxygen in K2ZnV2O7 was proved to be the key structural factor for transporting oxygen vacancies. The molecular dynamic simulation based on the interatomic potential approach revealed that long-range oxide ion diffusion was achieved by breaking and re-forming the 5-fold MO4 (M = Zn and V) tetrahedral rings. These findings enriched our knowledge of melilite and melilite-related materials, and creating oxygen vacancies in a melilite-related material may be a new strategy for developing novel oxide ion conductors.

We have developed room-temperature smectic liquid-crystalline (LC) ion conductors by the self-assembly of a zwitterionic mesogenic compound and a series of fluorinated lithium salts. The conductivity of lithium bis(trifluoromethylsulfonyl)imide LC complex reached 4 × 10–3 S cm–1 at ambient conditions. This LC complex sandwiched between two conductive polymer electrodes can be used in low-voltage mechanical actuators with a peak-to-peak bending deflection of ca. 20 mm upon ±1 V, 0.03 Hz excitation.

Burn injury represents a major global public healthcare problem and has a significant health-economics impact. In this study, we report on a 3D printed poly(lactic-co-glycolic acid) (PLGA) dermal scaffold containing bioactive PLGA for burn wound healing. Bioactive brush copolymers containing pendant side chains of PLGA and PEGylated Arg-Gly-Asp tripeptide (RGD) or hyaluronic acid (HA) were synthesized by ring-opening metathesis polymerization (ROMP). These copolymers exhibited good thermal stability for material processing using melt-extrusion-based methods. The copolymers were blended with commercial PLGA, extruded into filaments and 3D printed using fused filament fabrication (FFF) methods with incorporated porosities. The 3D printed scaffolds demonstrated good biocompatibility in in vitro cell assays and in vivo murine models. Porcine study based on partial thickness burn wound model showed that these PLGA scaffolds facilitated re-epithelization with reduced inflammation as compared to the clinical gold standard for second-degree burn wound treatment, Biobrane. The bioactive PLGA scaffolds presented herein are beneficial in wound healing and have therapeutic potential in burn wounds treatment.

In acidic media, many transition-metal phosphides are reported to be stable catalysts for the hydrogen evolution reaction (HER) but typically exhibit poor stability toward the corresponding oxygen evolution reaction (OER). A notable exception appears to be Rh2P/C nanoparticles, reported to be active and stable toward both the HER and OER. Previously, we investigated base-metal-substituted Rh2P, specifically Co2–xRhxP and Ni2–xRhxP, for HER and OER as a means to reduce the noble-metal content and tune the reactivity for these disparate reactions. In alkaline media, the Rh-rich phases were found to be most active for the HER, while base-metal-rich phases were found to be the most active for the OER. However, Co2–xRhxP was not stable in acidic media due to the dissolution of Co. In this study, the activity and stability of our previously synthesized Ni2–xRhxP nanoparticle catalysts (x = 0, 0.25, 0.50, 1.75) toward the HER and OER in acidic electrolyte are probed. For the HER, the Ni0.25Rh1.75P phase was found to have comparable geometric activity (overpotential at 10 mA/cmgeo2) and stability to Rh2P. In contrast, for OER, all of the tested Ni2–xRhxP phases had similar overpotential values at 10 mA/cmgeo2, but these were >2x the initial value for Rh2P. However, the activity of Rh2P fades rapidly, as does Ni2P and Ni-rich Ni2–xRhxP phases, whereas Ni0.25Rh1.75P shows only modest declines. Overall water splitting (OWS) conducted using Ni0.25Rh1.75P as a catalyst relative to the state-of-the-art (RuO2||20% Pt/C) revealed comparable stabilities, with the Ni0.25Rh1.75P system demanding an additional 200 mV to achieve 10 mA/cmgeo2. In contrast, a Rh2P||Rh2P OWS cell had a similar initial overpotential to RuO2||20% Pt/C, but is unstable, completely deactivating over 140 min. Thus, Rh2P is not a stable anode for the OER in acidic media, but can be stabilized, albeit with a loss of activity, by incorporation of nominally modest amounts of Ni.

As the Editors of ACS Materials Au, we are excited to share with you our inaugural Rising Stars in Materials Science! These 17 early career materials researchers from around the world are pushing scientific boundaries, conducting impactful research at the forefront of fundamental or applied research, and interfacing with other disciplines. Each of these Rising Stars has contributed a fantastic peer-reviewed Article, Letter, Perspective, or Review to the journal, and we are delighted to gather these contributions into a virtual special issue, showcasing the ACS Materials Au 2022 Rising Stars in Materials Science. The 2022 Rising Stars collection represents the breadth and depth of the discipline and provides new insights and directions for advancing materials research. ACS Materials Au’s 2022 Rising Stars in Materials Science. To introduce you to these scientists and their research, we are pleased to provide brief biographies and links to their contributions in the collection. We hope you enjoy getting to know these Rising Stars as much as we have, and that their science inspires you, as it does us! The novel biomaterials and polymers being developed by Dr. Brisbois and her research group hold great potential to overcome major biomedical device-associated challenges by providing hemocompatible, antimicrobial, and anti-inflammatory properties at device interfaces. Elizabeth J. Brisbois is currently an Assistant Professor in the School of Chemical, Materials, & Biomedical Engineering at the University of Georgia. She completed her National Institutes of Health Individual F32 Postdoctoral Fellowship at the University of Michigan Medical School in the Department of Surgery, where she worked in the Extracorporeal Life Support (ECLS) laboratory under the direction of Dr. Robert H. Bartlett (Emeritus Surgeon). She completed her Ph.D. in Chemistry at the University of Michigan in 2014 under the supervision of Dr. Mark E. Meyerhoff. She also obtained a B.S. degree in Chemistry and a B.S.Ed. in Secondary Education at Concordia University Nebraska in 2008. Dr. Brisbois’ current research is focused in the fields of polymeric biomaterials and the development of therapeutic biomolecules aimed at addressing challenges related to medical devices, diseases, and patient care. Her translational research aims to design novel multifunctional polymers and small molecule therapeutics, characterize these biomaterials for their properties in vitro, and evaluate their potential biomedical applications in clinically relevant animal models. More information about Dr. Brisbois and her research can be found here: http://brisboislab.uga.edu. Dr. Brisbois’ Rising Stars Review is titled “Recent Developments in Multifunctional Antimicrobial Surfaces and Applications toward Advanced Nitric Oxide-Based Biomaterials” (DOI: 10.1021/acsmaterialsau.2c00040). Dr. Canepa’s approaches can simulate a temperature–composition phase diagram in a fraction of the time usually needed by real experiments. This is crucial for the development of the next generation of electrode materials for power-hungry applications. Pieremanuele Canepa is an Assistant Professor in the Department of Materials Science and Engineering at the National University of Singapore (NUS) and has a joint appointment with the Department of Chemical and Biomolecular Engineering at the same institution. Dr. Canepa is also part of the Singapore-MIT Alliance. Between June 2013 and November 2016, Dr. Canepa was a Postdoctoral fellow under the guidance of Prof. Gerbrand Ceder initially at the Massachusetts Institute of Technology and later at Lawrence Berkeley National Laboratory. Between November 2016 and August 2018, Dr. Canepa was an independent Ramsay Memorial Fellow at the University of Bath. He received his bachelor’s (2006) and master’s (2008) degrees in Chemistry from the University of Torino. In 2012, Dr. Canepa was awarded his Ph.D. in Chemistry from the University of Kent under the supervision of Prof. Maria Alfredsson. At NUS Dr. Canepa runs the CARE research laboratory, which applies and develops computational methods to advance the understanding of materials properties for energy storage and conversion. The models derived from this research contribute to the rational design of new materials for clean energy technologies, such as electrode materials for batteries, ionic conductors, and liquid electrolytes for energy-dense and sustainable energy storage systems. More information about Dr. Canepa and his research can be found here: http://caneparesearch.org. Dr. Canepa’s Rising Stars Perspective is titled “Pushing Forward Simulation Techniques of Ion Transport in Ion Conductors for Energy Materials” (DOI: 10.1021/acsmaterialsau.2c00057). “Modelling Matters for Energy Revolution and Sustainable Environment” – the motto of my research. (S. Chakraborty) Sudip Chakraborty is leading the MAterials Theory for Energy Scavenging group (MATES Lab) in India’s premier theoretical research institute, Harish-Chandra Research Institute (HRI) Allahabad (Prayagraj), an Aided Institute of the Department of Atomic Energy, Government of India. After completing his Ph.D. on modeling semiconductor quantum dots, in a collaboration between Bhabha Atomic Research Centre (BARC) and University of Pune, he moved to Max Planck Institute, Düsseldorf, in March, 2011 as a Max Planck Postdoctoral Fellow. In February, 2013, he joined the Materials Theory Division, Uppsala University. In March, 2019, he came back to India and established his group in the Department of Physics, Indian Institute of Technology (IIT) Indore, as an Assistant Professor. Since May, 2021, he has been working at HRI, Allahabad as Reader. His current research group mainly focuses on development and application of electronic structure calculations for energy materials. He recently started working on materials properties for neuromorphic computing. More information about Dr. Chakraborty and his research can be found here: http://sudiphys.wixsite.com/ceslab-sudip/research-group. Dr. Chakraborty’s Rising Stars Perspective is titled: “Rationalization of Double Perovskite Oxides as Energy Materials: A Theoretical Insight from Electronic and Optical Properties” (DOI: 10.1021/acsmaterialsau.2c00031). The use of surface-supported clusters as molecular cocatalysts is a promising way to address the complexity that the design of modern photocatalytic materials entails. (A. Cherevan) Alexey Cherevan is currently a subgroup leader at TU Wien. After receiving his master’s degree in Chemistry (Moscow State University, 2010), he was awarded a Ph.D. scholarship from the Graduate School of Chemistry of Münster University (2011), which allowed him to pursue a doctoral degree in the fields of heterogeneous catalysis and hybrid nanomaterials, under the supervision of Prof. Dominik Eder. Supported by the Ewald-Wicke Scholarship (2012), Dr. Cherevan had the opportunity to visit the group of Prof. K. Domen (University of Tokyo), which helped him to complete his Ph.D. degree with distinction in 2014. After a short period of postdoctoral training with Prof. Dominik Eder (University of Münster, 2014–2015), Dr. Cherevan joined the division of Molecular Materials Chemistry of the TU Wien (2015) as a subgroup leader. Dr. Cherevan’s research group explores all-inorganic oxo- and thiometalate clusters in light-driven catalytic applications, aiming to generate green hydrogen and other solar fuels. More information on Dr. Cherevan and his research can be found here: http://www.tuwien.at/en/tch/mmc/team/dr-alexey-cherevan. Dr. Cherevan’s Rising Stars Article is titled “Immobilization of a [CoIIICoII(H2O)W11O39]7– Polyoxoanion for the Photocatalytic Oxygen Evolution Reaction” (DOI: 10.1021/acsmaterialsau.2c00025). The main focus of our research is the use of Cancer Nanotechnology for Precision Medicine in order to tackle crucial medical problems involved in the development of novel and highly effective diagnostic and therapy platforms for cancer. (J. Conde) João Conde is an Assistant Professor and Group Leader at NOVA Medical School, Universidade Nova de Lisboa. He received his Ph.D. in Biology, with a specialty in NanoBiotechnology from NOVA University and Universidad de Zaragoza in 2014, under the FP7 European Consortium NanoScieE+ – NANOTRUCK, for the development of multifunctional gold nanoparticles for gene silencing. He was then a Marie Curie Fellow at the Massachusetts Institute of Technology, Harvard-MIT Division for Health Sciences and Technology, and in the School of Engineering and Materials Science, Queen Mary University of London. From 2017 to 2019 he was a Junior Investigator at Instituto de Medicina Molecular. In 2019, he won an ERC Starting Grant to build a genetic biobarcode to profile breast cancer heterogeneity. He is also cofounder of the biotech company TargTex, Targeted Therapeutics for Glioblastoma Multiforme. Since 2020, he has also been part of the Global Burden of Disease (GBD) consortium from the Institute for Health Metrics and Evaluation (IHME), University of Washington. More information on Dr. Conde and his research can be found here: http://www.conde-nanolab.com/. Dr. Conde’s Rising Stars Perspective is titled “Gold Nanoconjugates for miRNA Modulation in Cancer Therapy: From miRNA Silencing to miRNA Mimics” (DOI: 10.1021/acsmaterialsau.2c00042). Our research bridges the gap between the understanding of molecular-level photophysics in solutions and the observed bulk-scale materials properties in condensed phases, which is crucial for the development of functional optical materials. (G. Han) Grace G. D. Han is currently a Landsman Assistant Professor of Chemistry at Brandeis University. Grace received her B.S. in Chemistry from POSTECH, Korea in 2010. Then she completed a Ph.D. in Chemistry at MIT with Prof. Timothy Swager in 2015, and her thesis focused on developing organic semiconductors for photovoltaics. Grace joined the Department of Materials Science and Engineering at MIT as a postdoctoral associate with Prof. Jeffrey Grossman before she started her faculty position at Brandeis in 2018. Her research group focuses on the design of light-responsive organic materials that incorporate photoswitches such as azoheteroarenes. The photoinduced reversible isomerization of switches translates to their phase transitions, which is investigated to control the storage of photon and thermal energy as well as the recycling of organocatalysts. More information about Dr. Han and her research can be found here: http://go.brandeis.edu/hangroup. Dr. Han’s Rising Stars Letter is titled “Light-Responsive Solid–Solid Phase Change Materials for Photon and Thermal Energy Storage” (DOI: 10.1021/acsmaterialsau.2c00055). The development of novel (bio)materials and devices is a key pillar of medical innovation and a major contributor to healthcare of the future. (I. Herrmann) Inge K. Herrmann currently is an Assistant Professor in the Department of Mechanical and Process Engineering at ETH Zürich and the Swiss Federal Laboratories for Materials Science and Technology (Empa). She obtained her B.Sc. in Chemical Engineering in 2006 and her Ph.D. in 2010 both from ETH Zürich. She joined the Beck-Schimmer Lab at University Hospital Zürich 2011–2013 and the Stevens Lab at Imperial College London 2013–2015 as a research associate. Her research is focused on medical technology innovation and her lab has developed novel surgical adhesives, multiscale medical imaging methods, and nanoparticle radioenhancers. More information about Dr. Herrmann and her research can be found here: www.nse.ethz.ch. Dr. Herrmann’s Rising Stars Perspective is titled “Fostering Medical Materials Innovation” (DOI: 10.1021/acsmaterialsau.2c00054). Our research group aspires to fully exploit the potential of solution-processed nanomaterials toward future electronics. (J. Kang) Joohoon Kang is an Assistant Professor of Materials Science and Engineering at Sungkyunkwan University (SKKU) in Korea. He received his B.S. and M.S. in Materials Science and Engineering from Yonsei University in 2009 and 2011, respectively, and his Ph.D. in Materials Science and Engineering from Northwestern University in 2018 under the supervision of Professor Mark C. Hersam. He was a postdoctoral fellow under Professor Peidong Yang at the University of California, Berkeley from 2018 to 2019. His current research interests include solution-based processing of nanoscale materials and their scalable applications in electronics, optoelectronics, and catalysis. More information about Dr. Kang and his research can be found here: http://mfmp.skku.edu. Dr. Kang’s Rising Stars Perspective is titled “Revisiting Solution-Based Processing of van der Waals Layered Materials for Electronics” (DOI: 10.1021/acsmaterialsau.2c00034). Fundamental studies on porous and crystalline materials and their developments will drive innovations in single-atom catalysts for CO2 reduction and rechargeable batteries. (Y. Kim) Yoonseob Kim is an Assistant Professor in the Department of Chemical and Biological Engineering at The Hong Kong University of Science and Technology. He studied Chemical Engineering at Hanyang University (2010), and received his Ph.D. from the Department of Chemical Engineering at the University of Michigan in 2016 (advisor: Prof. Nicholas A. Kotov). Subsequently, he worked in the Chemistry Department, Massachusetts Institute of Technology, as a postdoctoral associate from 2016 to 2019 with Prof. Timothy M. Swager. His research group currently synthesizes porous crystalline polymers and applies them to tackle energy and environmental problems. Current research topics include all-solid-state Li-metal batteries, solid electrolytes from covalent organic frameworks, and single-atom catalysts on covalent organic frameworks for CO2 reduction reaction. More information on Dr. Kim and his research can be found here: http://yoonseobkim.com/. Dr. Kim’s Rising Stars Perspective is titled “Single-Atom Catalysts on Covalent Organic Frameworks for CO2 Reduction” (DOI: 10.1021/acsmaterialsau.2c00061). Currently, the degradation of materials employed in electrochemical energy and conversion technologies limits their operational lifetime. If we can uncover how materials degrade at the fundamental level, we will be able to better predict, control, and ultimately develop regeneration strategies to recover their initial functionality. (P. Lopes) Pietro Papa Lopes is an Assistant Staff Scientist at the Materials Science Division, Argonne National Laboratory. Dr. Lopes obtained a bachelor’s degree in Chemistry from the University of Sao Paulo, Sao Carlos Chemistry Institute, in Brazil in 2007, and his Ph.D. in Chemistry under the supervision of Prof. Edson A. Ticianelli from the same university in 2013. He performed his postdoctoral research at Argonne National Laboratory in collaboration with Dr. Nenad Markovic from 2013 to 2016. His research is dedicated to advancing electrochemical processes critical to sustainable energy conversion and storage technologies, such as fuel cells, electrolyzers, and aqueous-based grid storage battery systems. His current focus is on understanding material structure–function–stability relationships at the fundamental level, employing well-defined materials and interfaces to uncover degradation mechanisms to allow the development of regeneration strategies and recover material functionality. More information about Dr. Lopes and his research can be found here: http://www.anl.gov/profile/pietro-papa-lopes. Dr. Lopes’ Rising Stars Perspective is titled “A Framework for the Relationships between Stability and Functional Properties of Electrochemical Energy Materials” (DOI: 10.1021/acsmaterialsau.2c00044). Our work uses operando magnetic resonance to probe battery degradation at the molecular-level to identify new routes to control and optimize electrochemical properties. (L. Marbella) Lauren Marbella is an Assistant Professor in the Department of Chemical Engineering at Columbia University. She received her B.S. degree in 2009 in Biochemistry from Duquesne University, where she did undergraduate research with Prof. Partha Basu. She went on to complete her Ph.D. in Chemistry at the University of Pittsburgh in 2016, under the direction of Prof. Jill Millstone. In 2017, she was named a Marie Curie Postdoctoral Fellow at the University of Cambridge, where she was supervised by Prof. Clare Gray, FRS. There, she was also named the Charles and Katharine Darwin Research Fellow, which recognizes the top junior fellow at Darwin College at the University of Cambridge. She joined the chemical engineering faculty at Columbia University in 2018. Her research group focuses on understanding the relationship between electrochemical performance and interfacial chemistry in devices for energy storage and conversion. Her research relies heavily on the use of nuclear magnetic resonance imaging (MRI) and spectroscopy to evaluate changes in material properties in real time to elucidate the chemical mechanisms underpinning degradation in Li and beyond Li-ion batteries. More information on Dr. Marbella and her research can be found here: http://www.marbella-lab.com. Dr. Marbella’s Rising Stars Article is titled “Transition Metal Dissolution Mechanisms and Impacts on Electronic Conductivity in Composite LiNi0.5Mn1.5O4 Cathode Films” (DOI: 10.1021/acsmaterialsau.2c00060). A fundamental requirement for advancing materials research is understanding how the nanoscale properties (e.g., defects) dictate the observed ensemble optoelectronic properties. (L. Nienhaus) Lea Nienhaus is an Assistant Professor in the Department of Chemistry at Florida State University. She obtained her B.Sc. in 2010 from the University of Ulm and then moved to the University of Illinois at Urbana–Champaign to pursue her Ph.D. in Physical Chemistry under the guidance of Professor Martin Gruebele. After successfully defending her Ph.D. in 2015, she moved to the Massachusetts Institute of Technology for her postdoctoral studies working on upconversion with Professor Moungi Bawendi. In 2018, she started her research program at Florida State University. Her work focuses on understanding the intricate (molecular level) optoelectronic processes occurring in hybrid organic/inorganic semiconductors by a combination of optical spectroscopy and scanning probe microscopy. More information on Dr. Nienhaus and her research can be found here: http://www.chem.fsu.edu/~nienhaus/index.html.. Dr. Nienhaus’ Rising Stars Perspective is titled “A Sensitizer of Purpose: Generating Triplet Excitons with Semiconductor Nanocrystals” (DOI: 10.1021/acsmaterialsau.2c00047). I hope that the materials we develop will help build a more sustainable and equitable future by providing access to efficient solar cells and affordable X-ray medical diagnostic tools. (M. Saidaminov) Makhsud I. Saidaminov is a Canada Research Chair Tier II in Advanced Functional Materials, and an Assistant Professor in the Department of Chemistry and Department of Electrical and Computer Engineering at the University of Victoria. Prior to this position, he was a Banting postdoctoral fellow with Prof. Edward H. Sargent at the University of Toronto (2017–2019), and a postdoctoral fellow with Prof. Osman Bakr at King Abdullah University of Science and Technology (2014–2016). Growing up in Tajikistan, he received his bachelor’s (2010) and Ph.D. (2013) degrees from Lomonosov Moscow State University. Dr. Saidaminov’s current research interests focus on physics and chemistry of hybrid materials, including halide perovskites for energy applications, all the way from sustainable harvesting of energy to its efficient consumption. More information on Dr. Saidaminov and his research can be found here: http://saidaminovlab.com/. Dr. Saidaminov’s Rising Stars Perspective is titled “High-Throughput Synthesis of Thin Films for the Discovery of Energy Materials: A Perspective” (DOI: 10.1021/acsmaterialsau.2c00028). Incorporating dynamic cross-links in polymer networks contributes to product life extension and waste reduction of 3D printed materials, and therefore offers a promising route toward closed-loop additive manufacturing. (V. Voet) Vincent Voet obtained his M.Sc. degree in Polymer Chemistry in 2010 at the University of Groningen in The Netherlands, after completing an external internship at Lawrence Berkeley National Laboratory, in California. He received his Ph.D. degree in 2015 for his research on the synthesis and self-assembly of fluorinated block copolymers for data storage applications in the research group of Prof. Dr. Katja Loos at the Zernike Institute for Advanced Materials, University of Groningen. Afterward, he stayed for one year in Lesotho, South Africa, where he developed new educational programs in Science at the Paray School of Nursing. In 2016, Dr. Voet started his career at NHL Stenden University of Applied Sciences in The Netherlands, and was appointed in 2018 as Associate Professor in the research group Circular Plastics. His current research focuses on (de)polymerization of polyesters, application of dynamic covalent polymer networks and 3D printing of sustainable photopolymers, in close collaboration with industrial partners and other knowledge institutes. More information about Dr. Voet and his research can be found here: http://www.nhlstenden.com/onderzoek/vincent-voet. Dr. Voet’s Rising Stars Perspective is titled “Closed-Loop Additive Manufacturing: Dynamic Covalent Networks in Vat Photopolymerization” (DOI: 10.1021/acsmaterialsau.2c00058). Nucleic acids–powerful building blocks for precise materials. (P. Wang) Pengfei Wang is currently a Professor at Shanghai Jiao Tong University School of Medicine. He earned his bachelor’s and master’s degrees in materials science and engineering from Tianjin University in 2007 and 2009, respectively. He then earned his doctoral degree in biomedical engineering from Purdue University in 2014 under the supervision of Prof. Chengde Mao. He conducted postdoctoral research study at Emory University School of Medicine in the lab of Prof. Yonggang Ke from 2014 to 2018. His research interest centers on building functional materials from the programmable self-assembly of nucleic acids for diverse applications in disease diagnostics and therapy. More information on Dr. Wang and his research can be found here: www.pengfeiwang.org. Dr. Wang’s Rising Stars Perspective is titled “Nucleic Acid Molecular Systems for In Vitro Detection of Biomolecules” (DOI: 10.1021/acsmaterialsau.2c00056). The thermal motion of atoms and molecules often dominates the electronic properties of molecular crystals. This Rising Stars Article investigates the relationship between molecular structure and the type of motion in the crystal. (O. Yaffe) Omer Yaffe is currently a senior scientist in the Chemical and Biological Physics Department at the Weizmann Institute of Science. He obtained a dual B.Sc. in Chemistry and Chemical Engineering at Ben Gurion University in 2005. He then completed his Ph.D. in the Department of Materials and Interfaces at the Weizmann Institute of Science in 2012, working with Prof. David Cahen. From 2013 to 2016, he worked as a postdoctoral fellow with Prof. Louis Brus and Prof. Tony Heinz at the Columbia University Energy Frontier Research Center. Dr. Yaffe’s group uncovers the connection between atomic and molecular structural dynamics and the functional properties of materials. They combine state-of-the-art optical spectroscopy methods, heat capacity, and electronic transport measurements to demonstrate that thermal fluctuations often profoundly affect the dielectric constant, heat capacity and transport, charge transport, and optical properties of materials. More information on Dr. Yaffe and his research can be found here: http://www.weizmann.ac.il/chembiophys/Yaffe/node/3. Dr. Yaffe’s Rising Stars Article is titled “Chemical Modifications Suppress Anharmonic Effects in the Lattice Dynamics of Organic Semiconductors” (DOI: 10.1021/acsmaterialsau.2c00020). New compounds enabling advances in material science are being thought out. We diversify the search for novel compounds by implementing unconventional synthesis methods. We further advance our understanding of how structure affects the properties by using an ensemble of synergistic characterization techniques. (J. Zaikina) Julia V. Zaikina has been an Assistant Professor at the Department of Chemistry, Iowa State University, since August 2017. Dr. Zaikina received her B.S. and M.S. degrees in Chemistry from Moscow State University, in 2005. She obtained her Ph.D. degree in 2008 while performing a joint research project between the Department of Chemistry, Moscow State University (Ph.D. advisor: Prof. Andrei V. Shevelkov) and Max-Plank-Institute for Chemical Physics of Solids, Dresden (Ph.D. adviser: Prof. Juri Grin). From 2008 to 2010, Dr. Zaikina did her first postdoctoral stint at the Department of Chemistry & Biochemistry, Florida State University, with Prof. Susan E. Latturner, and then in 2012, she joined the groups of Prof. Susan M. Kauzlarich and Prof. Alexandra Navrotsky at the Department of Chemistry, U. C. Davis for her second postdoctoral stint. Between 2014 and 2017, Dr. Zaikina held the position of research scientist in the group of Prof. Susan M. Kauzlarich and was a lecturer for general/inorganic chemistry in the Department of Chemistry, U. C. Davis. Her research interests are in the realm of inorganic and materials chemistry. In particular, her research utilizes unconventional synthesis routes to obtain complex solids and establishes their atomic and electronic structure to create new functional materials that address current scientific challenges in sustainable energy. More information about Dr. Zaikina and her research can be found here: http://group.chem.iastate.edu/Zaikina/index.html#. Dr. Zaikina’s Rising Stars Article is titled “Path Less Traveled: A Contemporary Twist on Synthesis and Traditional Structure Solution of Metastable LiNi12B8” (DOI: 10.1021/acsmaterialsau.2c00033). We look forward to watching these Rising Stars take their place in the firmament! We want to sincerely thank the researchers who contributed to this issue, to those in the community who nominated someone for this honor, our reviewers, and the materials research community that supports our early career scientists. Sincerely Yours, This article has not yet been cited by other publications. ACS Materials Au’s 2022 Rising Stars in Materials Science.

Phonons play a crucial role in the thermodynamic and transport properties of solid materials. Nevertheless, rather little is known about phonons in organic semiconductors. Thus, we employ highly reliable quantum mechanical calculations for studying the phonons in the α-polymorph of quinacridone. This material is particularly interesting, as it has highly anisotropic properties with distinctly different bonding types (H-bonding, π-stacking, and dispersion interactions) in different spatial directions. By calculating the overlaps of modes in molecular quinacridone and the α-polymorph, we associate Γ-point phonons with molecular vibrations to get a first impression of the impact of the crystalline environment. The situation becomes considerably more complex when analyzing phonons in the entire 1st Brillouin zone, where, due to the low symmetry of α-quinacridone, a multitude of avoided band crossings occur. At these, the character of the phonon modes typically switches, as can be inferred from mode participation ratios and mode longitudinalities. Notably, avoided crossings are observed not only as a function of the length but also as a function of the direction of the phonon wave vector. Analyzing these avoided crossings reveals how it is possible that the highest frequency acoustic band is always the one with the largest longitudinality, although longitudinal phonons in different crystalline directions are characterized by fundamentally different molecular displacements. The multiple avoided crossings also give rise to a particularly complex angular dependence of the group velocities, but combining the insights from the various studied quantities still allows drawing general conclusions, e.g., on the relative energetics of longitudinal vs transverse deformations (i.e., compressions and expansions vs slips of neighboring molecules). They also reveal how phonon transport in α-quinacridone is impacted by the reinforcing H-bonds and by π-stacking interactions (resulting from a complex superposition of van der Waals, charge penetration, and exchange repulsion).