Aluminum-doped zinc oxide (AZO) is considered as a promising candidate as transparent conductive oxide (TCO) for silicon heterojunction solar cells due to its high carrier density, nontoxic nature, and low cost. Herein, it is presented that the transparency of the AZO film can be optimized through co-sputtering of AZO and molybdenum oxide (MoOx). Furthermore, aluminum and molybdenum co-doped zinc oxide (MAZO) can be used as both the TCO layer and electron-selective contact (ESC) for silicon heterojunction solar cells. The surface morphology, cation oxidation state, and optical and electrical properties of all MAZO films are characterized. It is found that the transmittance of all MAZO films is significantly increased at a wavelength of 450–800 nm due to MAZO with a stronger Zn–O bond and a wider band gap. The conductivity of MAZO films is approximate to AZO films at a low MoOx target deposit power (50 W), and the sheet resistance of MAZO films increases significantly by increasing the deposition power up to 100 W. Finally, the optimized MAZO films are used as TCO and ESC for silicon heterojunction solar cells, showing a power conversion efficiency of 19.58%. The results show an effective stage to improve the optical properties of AZO through co-doping and the possibility of applying MAZO as a dual-functional layer for silicon solar cells.

Natural phenolic compounds have antioxidant properties owing to their free radical-scavenging capability. The combined effect of a mixture of phenolic compounds has been studied; however, the detailed investigation for finding a correlation between single phenolic molecules and antioxidant activity has not been explored. Herein, we revealed that the number of phenolic hydroxyl groups in phenolics played a central role in their antioxidant capacity. Based on the finding, tannic acid showed the most effective antioxidant potential, e.g., 76% in tannic acid versus 22% in vitamin C as a standard antioxidant component. Because cancer progression is closely related to oxidative processes at the cellular level, we further applied the surface treatment of tannic acid drug-delivery nanocarriers. Tannic acid-loaded nanocarriers reduced reactive oxygen species of cancer cells as much as 41% of vehicle treatment and remodeled cytoskeletal network. By a gelatin degradation study, TA-loaded nanocarrier-treated cells induced 44.6% reduction of degraded area than vehicle-treated cells, implying a potential of blocking invasiveness of cancer cells.

Multidentate hydrogen-bonding interactions are a promising strategy to improve underwater adhesion. Molecular and macroscale experiments have revealed an increase in underwater adhesion by incorporating multidentate H-bonding groups, but quantitatively relating the macroscale adhesive strength to cooperative hydrogen-bonding interactions remains challenging. Here, we investigate whether tridentate alcohol moieties incorporated in a model epoxy act cooperatively to enhance adhesion. We first demonstrate that incorporation of tridentate alcohol moieties leads to comparable adhesive strength with mica and aluminum in air and in water. We then show that the presence of tridentate groups leads to energy release rates that increase with an increase in crack velocity in air and in water, while materials lacking these groups do not display rate-dependent adhesion. We model the rate-dependent adhesion to estimate the activation energy of the interfacial bonds. Based on our data, we estimate the lifetime of these bonds to be between 2 ms and 6 s, corresponding to an equilibrium activation energy between 23kBT and 31kBT. These values are consistent with tridentate hydrogen bonding, suggesting that the three alcohol groups in the Tris moiety bond cooperatively form a robust adhesive interaction underwater.

In this work, decomposable and combustible flexible organic transistors with a cellulose-based dielectric and substrate were demonstrated in an effort to produce biodegradable systems for eco-sustainable electronics. High-k cyanoethyl cellulose (CEC) was explored as a suitable gate dielectric candidate for enhancing the biodegradability of flexible devices fabricated on a paper substrate. The fabricated flexible biodegradable transistors exhibited high performance for −5 V operation with excellent saturation in the output characteristics along with remarkable environmental, operational, electromechanical, and thermal stability. Upon thermal annealing, the performance of the devices did not degrade till the temperature of 60 °C, indicating their suitability for practical operating environments. Moreover, the devices exhibited decent stability upon exposure to very high humidity. Most importantly, these devices were decomposed in water-rich soil in 19 days due to the microorganisms present in soil, confirming the excellent biodegradability, which is highly essential for eco-sustainable electronics. Moreover, the combustion of the devices in fire, one of the quickest methods for degradation, led to a significant reduction in mass of more than 75%, leaving ashes primarily consisting of the remains of Ag bottom-gate and Au source/drain electrodes. Our results on the demonstration of flexible devices with full decomposability in soil and high combustibility can be a significant step toward the preparation of fully biodegradable flexible electronics to minimize the effects of e-waste on environment and soil.

Transducers made from graphene-type materials are widely used in sensing applications. However, utilization of graphene oxide obtained from electrochemical exfoliation of graphite (EGO) has remained relatively unexplored. In this study, electrochemical cocaine aptasensors based on large-size EGO flakes were investigated. In particular, the influence of the following parameters on the sensor performance was examined: (i) aptamer’s terminal group (−NH2 vs −OH), (ii) functionalization of EGO with the aptamer via physical adsorption and covalent immobilization, and (iii) intrinsic electrochemical properties of EGO such as the electrochemical surface area (ESA) and standard rate constant of electron transfer (k0). The results demonstrate that EGO-based electrochemical aptasensors fabricated by physical adsorption with an NH2-modified aptamer have very good reproducibility, shelf-life stability, and high sensitivity for detecting cocaine with a detection limit of 50 nM. Their performance is comparable to that of the aptasensors prepared using the covalent immobilization. Additionally, it is shown that EGO materials with high ESA and k0 can enhance the sensing performance. The fast (less than 10 min) and strong adsorption of the NH2-modified cocaine aptamer on the surface of large EGO flakes makes the fabrication of the sensing platform simple and rapid. This simple approach has the potential to simplify the fabrication of sensors.

Organic capping agents are a ubiquitous and crucial part of preparing reproducible and homogeneous batches of nanomaterials, particularly nanocrystals with well-defined facets. Despite studies reporting surface ligands (e.g., capping agents) having a non-negligible role in catalytic behavior, their impact is less understood in contaminant adsorption, an important consideration given their potential to obfuscate facet-dependent trends in performance. To ascribe observed behaviors to the facet or the ligand, this report evaluates the impact of poly(N-vinyl-2-pyrrolidone) (PVP), a commonly utilized capping agent, on the adsorption performance of nanohematite particles of varying prevailing facet in the removal of selenite (Se(IV)) as a model system. The PVP capping agent reduces the available surface area for contaminant binding, thus resulting in a reduction in overall Se(IV) adsorbed. However, accounting for the effects of surface area, {012}-faceted nanohematite demonstrates a significantly higher sorption capacity for Se(IV) compared with that of {001}-faceted nanohematite. Notably, chemical treatment is minimally effective in removing strongly bound PVP, indicating that complete removal of surface ligands remains challenging.

Enzyme immobilization enables the fabrication of flexible and powerful biocatalytic systems that can meet the needs of green and efficient development in various fields. However, restricted electron and mass transfer during enzymatic reactions and disruption of the enzyme structure during encapsulation limit the wide application of the immobilized enzyme systems. Herein, we report an encapsulation strategy based on hollow-shell-layered double hydroxides (LDHs; ZnCo-LDH) for green and nondestructive enzyme immobilization. Benefiting from the protective and enzyme-friendly microenvironment provided by the hydrophilic hollow structure of ZnCo-LDH, the encapsulated enzyme maintains a nearly natural enzyme biostructure and enhanced stability. Notably, mesoporous ZnCo-LDH with excellent electrical properties considerably facilitates electron and mass transport during enzymatic reactions, exhibiting 5.56 times the catalytic efficiency of free enzymes or traditional enzyme encapsulation systems. The current study broadens the family of encapsulated carriers and alleviates the trade-off between enzyme stability and catalytic activity in the encapsulated state, presenting a promising avenue for the industrial application of the enzyme.

Nickel-rich layered oxides are promising cathodes in commercial materials for lithium-ion batteries. However, the increase of the nickel content leads to the decay of cyclic performance and thermal stability. Herein, in situ surface-fluorinated W-doping LiNi0.90Co0.05Mn0.05O2 cathodes enhance integral lithium-ion migration (transfer in bulk and diffusion in the interface) kinetics by synergistically solving the problems of bulk and interface structural degradation. Owing to the introduction of tungsten, the growth of primary particles is regulated toward the (003) crystal plane and with the acicular structure, which further stabilizes the bulk structure during cycling. Moreover, the LiF coating layer on the cathode/electrolyte interface physically isolates the attack of the electrolyte on the surface cathodes and accelerates the lithium-ion diffusion rate, ultimately ameliorating the interfacial dynamics and structural stability. Dual-modified LiNi0.90Co0.05Mn0.05O2 exhibits superior electrochemical properties, especially more remarkable cyclic retention (88.16% vs 70.44%) after 100 cycles at 1 C and more outstanding high current rate properties (173.31 mAh·g–1 vs 135.97 mAh·g–1) at 5 C than the pristine one. This work emphasizes the probability of an integrated optimization strategy for Ni-rich materials, which provides an innovative idea for ameliorating (bulk and interfacial) structure degradation and promoting the diffusion of lithium ions during cycling.

Polymer-derived processing of ceramics (PDC) is an efficient technique to prepare porous nanocomposites with precise control over their phase composition and in relation to the Si-based ceramic matrix containing free carbon. The microstructure of these nanocomposites can be fine-tuned at the molecular scale for obtaining necessary properties by tailoring the chemical configuration of the preceramic polymer. In the present work, vanadium-based nanocomposites were synthesized as oxygen reduction reaction (ORR) catalysts with the objective of elucidating the effect of microstructure changes on catalytic efficiency. For this purpose, a single-source precursor (SSP) was synthesized by crosslinking phenyl- and hydrido-substituted polysiloxane and vanadium acetylacetonate followed by pyrolysis at 1100 °C. The resulting solid was composed of sparsely distributed nanodomains of vanadium carbide (VC) crystals precipitated within an amorphous silicon oxycarbide (−Si–O–C−) matrix. High-temperature treatment of the pyrolyzed samples beyond 1300 °C induced the crystallization of β-SiC as well as VC. Furthermore, Raman spectroscopy confirmed the segregation of sp2-hybridized, turbostratic free carbon. The samples exposed to 1300 °C revealed a specific surface area of 239 m2/g. The electrocatalytic activity of the sample heat-treated at 1300 °C showed the best performance with respect to the ORR performance with onset potential (Eo) and half-wave potential (E1/2) values of 0.81 and 0.72 V, respectively. In addition, improved kinetics with a Tafel slope of 57 mV/dec and enhanced current density in the diffusion-controlled region (Id) of 3.7 mA/cm2 were observed for this sample. The increase in Eo was attributed to the optimal interfacial characteristics between the VC and SiOC matrix with better embedment of VC with free carbon through V–C bonds. The higher E1/2 and faster kinetics are because of the higher electronic conductivity caused by the free carbon effectively connecting metallic VC crystallites. Besides, the higher specific surface area of this sample enhanced Id.

The self-organization of embryonic stem cells (ESCs) into organized tissues with three distinct germ layers is critical to morphogenesis and early development. While the regulation of this self-organization by soluble signals is well established, the involvement of mechanical force gradients in this process remains unclear due to the lack of a suitable platform to study this process. In this study, we developed a 3D microenvironment to examine the influence of mechanical tension gradients on ESC-patterned differentiation during morphogenesis by controlling the geometrical signals (shape and size) of ESC colonies. We found that changes in colony geometry impacted the germ layer pattern, with Cdx2-positive cells being more abundant at edges and in areas with high curvatures. The differentiation patterns were determined by geometry-mediated cell tension gradients, with an extraembryonic mesoderm-like layer forming in high-tension regions and ectodermal-like lineages at low-tension regions in the center. Suppression of cytoskeletal tension hindered ESC self-organization. These results indicate that geometric confinement-mediated mechanical tension plays a crucial role in linking multicellular organization to cell differentiation and impacting tissue patterning.

In the field of electromagnetic shielding, it has become an important trend to manufacture thinner and better-performing electromagnetic interference (EMI) shielding materials. However, EMI shielding materials that are recyclable and resistant to extreme environments are of great significance for sustainable development and expanding their application areas. In this study, a composite paper with a “rebar-concrete” layered structure through the vacuum-assisted filtration approach by utilizing basalt fibers (BF) and aramid nanofibers (ANFs) with excellent temperature resistance and multiwalled carbon nanotubes with high electrical conductivity was prepared. The composite paper not only delivers a high electrical conductivity of 15.9 S cm–1 and a high electromagnetic interference shielding efficiency (EMI SE) of 24.6 dB but also exhibits a high specific shielding efficiency (SSE/t) of 12,504 dB cm2 g–1 at a thickness of 48 μm. Thanks to the excellent thermal stability of basalt fibers and aramid nanofibers, the composite paper exhibits long-term stable EMI shielding performance and structural integrity in various extreme environments, including fire, high/low temperature (−196 to 300 °C), and acid–base corrosion. Furthermore, the BF/ANF/CNT composite paper also shows excellent Joule heating performance, rapid electrothermal response, and good temperature controllability. Based on these excellent properties, the BF/ANF/CNT composite paper shows tremendous potential for practical applications to meet the requirements of various extreme environments.

The theoretical efficiency limit of fluorescence organic light-emitting diodes (OLEDs) was successfully surpassed by utilizing the localized surface plasmon resonance (LSPR) effect with conventional emissive materials. The interaction between polaritons and plexcitons generated during the LSPR process was also analyzed experimentally. As a result, the external quantum efficiency (EQE) increased dramatically from 6.01 to 15.43%, significantly exceeding the theoretical efficiency limit of fluorescent OLEDs. Additionally, we introduced a new concept of the LSPR effect, called “LSPR sensitizer”, which allowed for simultaneous improvement in color conversion and efficiency through cascade transfer of the LSPR effect. To the best of our knowledge, the EQE and the current efficiency of our LSPR–OLED are the highest among LSPR-based fluorescent OLEDs to date.

In this study, a Ag/WO3/InGaN hybrid heterostructure was successfully developed by sputtering and molecular beam epitaxy techniques, to obtain unique Ag nanospheres adorned with cauliflower-like WO3 nanostructure over the InGaN nanorods (NRs). Exploiting the localized surface plasmon resonance of Ag, the Ag/WO3/InGaN heterostructure exhibited superior photoabsorption ability in the visible region (400–700 nm) of the solar spectrum, with a surface plasmon resonance band centered around 440 nm. Comprehensive analysis through photoluminescence spectroscopy, photocurrent measurements, and electrochemical impedance spectroscopy revealed that the Ag/WO3/InGaN hybrid heterostructure significantly enhances the charge carrier separation and transfer kinetics leading to improved overall photoelectrochemical (PEC) performance. The photocurrent density of the Ag/WO3/InGaN photoanode is 1.17 mA/cm2, which is about 2.72 times higher than that of pure InGaN NRs under visible light irradiation. The photoanode exhibited excellent stability for about 12 h. From the study, it has been found that the maximum applied bias photon-to-current efficiency (ABPE) is ∼1.67% at the applied bias of 0.6 V. The improved PEC water splitting efficiency of the Ag/WO3/InGaN photoanode is attributed to the synergistic effects of localized surface plasmon resonance (LSPR), efficient charge carrier separation and transport, and the presence of a Schottky junction. Consequently, the plasmonic metal-assisted heterojunction-based semiconductor Ag/WO3/InGaN demonstrates immense potential for practical applications in photoelectrochemical water splitting.

The increasing concern about climate change has led scientists around the world to develop clean energy technologies that may replace the traditional use of fossil fuels. A promising approach is the utilization of unicellular organisms as electron donors in bio-fuel cells. To date, this method has been limited to microorganisms such as bacteria, yeast, and microalgae. In this work, we show for the first time the concept of using mammalian cell cultures and organoids as electron donors in biofuel cells. We apply cyclic voltammetry to show that upon association of ARPE19 cells with the anode, they release reducing molecules to produce electricity. Furthermore, we apply 2D-fluorescence measurements and show that upon illumination, photosensitive stem cell-derived retinal organoids, which consist of rod photoreceptors and interneurons, secrete NADH and NADPH molecules that can donate electrons at the anode to produce photocurrent.

Photothermal therapy (PTT) has emerged as a promising strategy for the treatment of tumors. However, the intrinsic self-repair mechanism of cells and the nonspecific photothermal effect of photothermal agents can result in poor treatment outcomes and normal tissue injury. To address this issue, we developed a dual light activatable perylenediimide derivative (P-NO) for nitric oxide-enhanced PTT. P-NO can self-assemble into nanoparticles in aqueous solutions. The P-NO nanoparticles are capable of releasing both NO and a photothermal molecule (P-NH) upon green light irradiation. The simultaneous release of NO and P-NH activates the photothermal effect and inhibits cell protection autophagy, thereby improving the therapeutic efficacy of PTT under near-infrared (NIR) light. Moreover, the switch on of NIR fluorescence allows real-time monitoring of the release of P-NH. Remarkably, in a mouse subcutaneous tumor model, significant tumor ablation can be achieved following dual light activated photothermal gas therapy. This work offers a promising and straightforward approach to constructing activatable perylenediimide-based photothermal agents for enhancing the effectiveness of photothermal gas therapy.

The pyrolysis of metal–organic frameworks (MOF) has been widely used approach to generate hierarchical structures with the corresponding metal, metal carbide, or metal oxide nanoparticles embedded in a porous carbon matrix with a high specific surface area for industrial catalysis, energy storage and transfer, etc. MOF-derived heterogeneous catalysts can be constructed by the encapsulation of carbon dots (CDs) with plenty of hydroxyl and amine groups to enhance the performance of the final product. Controlled formation of metallic carbon structures at the nanoscale, especially matter cycling and transformation on the nanoscale interface, is important for the production of industrial catalysts as well as the research of materials science and engineering progress. However, the mass transfer at the nanoscale during the processing of MOF pyrolysis remains less understood due to the lack of direct observation. Herein, by using in situ environmental transmission electron microscopy, real-time imaging and quantitative evolution of porous carbon decorated with metal species by the pyrolysis of CDs-encapsulated zeolitic imidazolate framework-67 are achieved. The migration of Co, the flow of aggregates, and the growth of carbon nanotubes observed in the nanoscale pyrolysis laboratory working at 600 °C with an air atmosphere are present. Experimental studies based on reduction and oxidation reaction models reveal that the synergistic effect between doped graphite nitrogen and confined Co nanoparticles is beneficial for boosting catalytic performance.

Quantification in the driving patterns of activity descriptors on structure–activity relationships and reaction mechanisms over heterogeneous catalysts is still a great challenge and needs to be addressed urgently. Herein, with the example of typical Mn-based catalysts, based on the activity regularity and many characterizations, the chemisorbed oxygen density (ρOβ) and particle size (dTEM) have been proposed as the two-dimensional descriptors for selective catalytic reduction of NO, whose role is in quantifying the contents of vacancy defects and the amounts of active sites located on terraces or interfaces, respectively. They can be utilized to construct and quantify the driving patterns for the structure–activity relationships and reaction mechanisms of NO reduction. As a consequence, a complementary modulation for Ea by ρOβ and dTEM is described quantitatively in terms of the fitted functions. Moreover, based on the structure–activity relationships and the quantification laws of in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), the reaction efficiency (RE) of the specific combined NOx-intermediate is identified as the trigger to drive the Langmuir–Hinshelwood mechanism and modulated by the descriptors complementally and collaboratively following the fitted quantification functions. Either of the two descriptors at its lower values plays a dominant role in regulating Ea and RE, and the dominant factor evolves progressively: dTEM ↔ coupling dTEM with ρOβ ↔ ρOβ, when the dependency of Ea and RE on the descriptors is adopted to identify the dominant factor and domains. Therefore, this work has quantitatively accounted for the essence of activity modulation and may provide insight into the quantitative driving patterns for reaction activity and mechanism.

Ammonia is produced through the energy-intensive Haber–Bosch process, which undergoes catalytic oxidation for the production of commercial nitric acid by the senescent Ostwald process. The two energy-intensive industrial processes demand for process sustainability. Hence, single-step electrocatalysis offers a promising approach toward a more environmentally friendly solution. Herein, we report a 10-electron pathway associated one-step electrochemical dinitrogen oxidation reaction (N2OR) to nitric acid by manganese phthalocyanine (MnPc) hollow nano-structures under ambient conditions. The catalyst delivers a nitric acid yield of 513.2 μmol h–1 gcat–1 with 33.9% Faradaic efficiency @ 2.1 V versus reversible hydrogen electrode. The excellent N2OR performances are achieved due to the specific-selectivity, presence of greater number of exposed active sites, recyclability, and long period stability. The extended X-ray absorption fine structure confirms that Mn atoms are coordinated to the pyrrolic and pyridinic nitrogen via Mn–N4 coordination. Density functional theory-based theoretical calculations confirm that the Mn–N4 site of MnPc is the main active center for N2OR, which suppresses the oxygen evolution reaction. This work provides a new arena about the successful example of one step nitric acid production utilizing a Mn–N4 active site-based metal phthalocyanine electrocatalyst by dinitrogen oxidation for the development of a carbon-neutral sustainable society.

Although cesium halide lead (CsPbX3, X = Cl, Br, I) perovskite quantum dots (QDs) have excellent photovoltaic properties, their unstable characteristics are major limitations to application. Previous research has demonstrated that the core–shell structure can significantly improve the stability of CsPbX3 QDs and form heterojunctions at interfaces, enabling multifunctionalization of perovskite materials. In this article, we propose a convenient method to construct core–shell-structured perovskite materials, in which CsPbBr3@CsPb2Br5 core–shell micrometer crystals can be prepared by controlling the ratio of Cs+/Pb2+ in the precursor and the reaction time. The materials exhibited enhanced optical properties and stability that provided for further postprocessing. Subsequently, CsPbBr3@CsPb2Br5@TiO2 composites were obtained by coating a layer of dense TiO2 nanoparticles on the surfaces of micrometer crystals through hydrolysis of titanium precursors. According to density functional theory (DFT) calculations and experimental results, the presence of surface TiO2 promoted delocalization of photogenerated electrons and holes, enabling the CsPbBr3@CsPb2Br5@TiO2 composites to exhibit excellent performance in the field of photocatalysis. In addition, due to passivation of surface defects by CsPb2Br5 and TiO2 shells, the luminous intensity of white light-emitting diodes prepared with the materials only decayed by 2%–3% at high temperatures (>100 °C) when working for 24 h.

As a common defect-capping ligand in metal–organic frameworks (MOFs), the hydroxyl group normally exhibits Brønsted acidity or basicity, but the presence of inherent hydroxyl groups in the MOF structure makes it a great challenge to identify the exact role of defect-capping hydroxyl groups in catalysis. Herein, we used hydroxyl-free MIL-140A as the platform to generate terminal hydroxyl groups on defect sites via a continuous post-synthetic treatment. The structure and acidity of MIL-140A were properly characterized. The hydroxyl-contained MIL-140A-OH exhibited 4.6-fold higher activity than the pristine MIL-140A in methanol dehydration. Spectroscopic and computational investigations demonstrated that the reaction was initiated by the respective adsorption of two methanol molecules on the terminal-OH and the adjacent Zr vacancy. The dehydration of the adsorbed methanol molecules then occurred in the Brønsted–Lewis acid site co-participated associative pathway with the lowest energy barrier.