Amorphous nanomaterials have emerged as potential candidates for energy storage and conversion owing to their amazing physicochemical properties. Recent studies have proved that the manipulation of amorphous nanomaterials can further enhance electrochemical performance. To date, various feasible strategies have been proposed, of which amorphous/crystalline (a-c) heterointerface engineering is deemed an effective approach to break through the inherent activity limitations of electrode materials. The following review discusses recent research progress on a-c heterointerfaces for enhanced electrochemical processes. The general strategies for synthesizing a-c heterojunctions are first summarized. Subsequently, we highlight various advanced applications of a-c heterointerfaces in the field of electrochemistry, including for supercapacitors, batteries, and electrocatalysts. We also elucidate the synergistic mechanism of the crystalline phase and amorphous phase for electrochemical processes. Lastly, we summarize the challenges, present our personal opinions, and offer a critical perspective on the further development of a-c nanomaterials.

The performance of tin-based perovskite solar cells has been substantially hampered by voltage loss caused by energy level mismatch, charge recombination, energetic disorder, and other issues. Here, a fused-ring electron acceptor based on indacenodithiophene (IDIC) was for the first time introduced as a transition layer between a tin-based perovskite layer and a C60 electron transport layer, leading to better matched energy levels in the device. In addition, coordination interactions between IDIC and perovskite improved the latter's crystallinity. The introduction of IDIC raised the power conversion efficiency from 8.98% to 11.5% and improved the device's stability. The decomposition mechanism of tin-based perovskite was also revealed by detecting the optical properties of perovskite microdomains through innovative integration of confocal laser scanning microscopy and photoluminescence spectroscopy.

Li–CO2 batteries, which integrate CO2 utilization and electrochemical energy storage, offer the prospect of utilizing a greenhouse gas and providing an alternative to the well-established lithium-ion batteries. However, they still suffer from rather limited reversibility, low energy efficiency, and sluggish CO2 redox reaction kinetics. To address these key issues, a nanoporous Ni3Al intermetallic/Ni heterojunction (NP–Ni3Al/Ni) is purposely engineered here via an alloying–etching protocol, whereby the unique interactions between Al and Ni in Ni3Al endow NP-Ni3Al/Ni with optimum reactant/product adsorption and thus unique catalytic performance for the CO2 redox reaction. Furthermore, the nanoporous spongy structure benefits mass transport as well as discharge product storage and enables a rich multiphase reaction interface. In situ Raman studies and theoretical simulations reveal that both CO2 reduction and the co-decomposition of Li2CO3 and C are distinctly promoted by NP-Ni3Al/Ni, thereby greatly improving catalytic activity and stability. NP-Ni3Al/Ni offers promising application potential in Li–CO2 batteries, with its scalable fabrication, low production cost, and superior catalytic performance.

Crystal structure determines electrochemical energy storage characteristics; this is the underlying logic of material design. To date, hundreds of electrode materials have been developed to pursue superior performance. However, it remains a great challenge to understand the fundamental structure–performance relationship and achieve quantitative crystal structure design for efficient energy storage. In this review, we introduce the concept of crystal packing factor (PF), which can quantify crystal packing density. We then present and classify the typical crystal structures of attractive cathode/anode materials. Comparative PF analyses of different materials, including polymorphs, isomorphs, and others, are performed to clarify the influence of crystal packing density on energy storage performance through electronic and ionic conductivities. Notably, the practical electronic/ionic conductivities of energy storage materials are based on their intrinsic characteristics related to the PF yet are also affected by extrinsic factors. The PF provides a novel avenue for understanding the electrochemical performance of pristine materials and may offer guidance on designing better materials. Additional approaches involve size regulation, doping, carbon additives, and other methods. We also propose extended PF concepts to understand charge storage and transport behavior at different scales. Finally, we provide our insights on the major challenges and prospective solutions in this highly exciting field.

Covalent organic polymers (COPs) have emerged as a unique class of luminescent polymers with pre-designed quasi-ordered architectures. However, their layered stacks and limited solubility preclude further processing for large-scale applications in devices, especially optoelectronic equipment. Herein, a universal strategy to adjust the electron donor–acceptor (D-A) moieties of the building blocks in COPs is proposed, achieved by in situ charge exfoliation of COP blocks into few-layer true solutions in (Lewis) acid and base media. The electron D-A moieties of the building blocks endow the COPs with the ability to accept or donate electrons, by altering the electron cloud distribution as well as the relative energy levels of the frontier molecular orbitals. The resultant soluble COPs can easily be processed into a uniform film by solution processing via the spin-coat method. The obtained COP-N achieves efficient and stable perovskite electroluminescence as a novel hole injection material on indium tin oxide, and the operating lifetime for a perovskite quantum dot light-emitting diodes device exceeds that of a poly(ethylene dioxythiophene):polystyrene sulphonate counterpart. This straightforward electronic regulation strategy provides a new avenue for the rational synthesis of processable reticular molecular polymers for practical electronic devices.

Owing to their outstanding optoelectronic properties, all-inorganic CsPbBr3 perovskite nanocrystals (NCs) are regarded as excellent materials for various optoelectronic applications. Unfortunately, their practical applications are limited by poor stability against water, heat, and polar solvents. Here, we propose a facile synthesis strategy for CsPbBr3@Cs4PbBr6 NCs via tetraoctylammonium bromide ligand induction at room temperature. The resulting CsPbBr3@Cs4PbBr6 NCs show a high photoluminescence quantum yield of 94%. In order to prevent Cs4PbBr6 from being converted back to CsPbBr3 NCs when exposed to water, a second coating layer of SiO2 is formed on the surface of the CsPbBr3@Cs4PbBr6 NCs by the facile hydrolysis of tetramethoxysilane. The resulting CsPbBr3@Cs4PbBr6/SiO2 NCs with their double coating structure have outstanding stability against not only a polar solvent (ethanol) but also water and heat. The as-prepared CsPbBr3@Cs4PbBr6/SiO2 NCs serve as green emitters in efficient white light-emitting diodes (WLEDs) with a high color rendering index (CRI) of 91 and a high power efficiency 59.87 lm W−1. Furthermore, the use of these WLEDs in visible light communication (VLC) results in a maximum rate of 44.53 Mbps, suggesting the great potential of the reported methods and materials for solid-state illumination and VLC.

Using inorganic fibrous membranes as protective layers has yielded success in suppressing dendrite growth. However, conventional fibrous membranes usually have large voids and low affinity for Li, promoting inhomogeneous charge distribution and allowing some dendrites to grow. Herein, we introduce a highly aligned TiO2/SiO2 (A-TS) electrospun nanofiber membrane as a protective layer for the Li metal anode. The A-TS membrane is fabricated by a custom-made electrospinning system with an automatic fiber alignment collector that allows control of the fibers’ orientation. At the scale of the individual fibers, their high binding energies with Li can attract more “dead” Li by reacting with the SiO2 component of the composite, avoiding uncontrollable deposition on the metal anode. At the membrane scale, these highly ordered structures achieve homogeneous contact and charge distribution on the Li metal surface, leaving no vulnerable areas to nucleate dendrite formation. Additionally, the excellent mechanical and thermal stability properties of the A-TS membrane prevent any potential puncturing by dendrites or thermal runaway in a battery. Hence, an A-TS@Li anode exhibits stable cycling performance when used in both Li–S and Li–NCM811 batteries, highlighting significant reference values for the future design and development of high-energy-density metal-based battery systems.

With their intrinsic safety and environmental benignity, aqueous Zn-ion batteries (ZIBs) have been considered the most appropriate candidates for replacing alkali metal systems. However, polycrystalline Zn anodes in aqueous environments still pose enormous issues, such as dendrite growth and side reactions. Although many efforts have been made to address these obstacles through interphase modification and electrolyte design, researchers have not been able to improve the inherent thermodynamic stability and ion deposition behavior of the Zn anode. It is imperative to understand and explore advanced anode construction methods from the perspective of crystallinity. This review delves into the feasibility of precisely regulating the crystallographic features of metallic zinc, examines the challenges and merits of reported strategies for fabricating textured zinc, and offers constructive suggestions for the large-scale production and commercial application of aqueous ZIBs.

Aqueous rechargeable Li/Na-ion batteries have shown promise for sustainable large-scale energy storage due to their safety, low cost, and environmental benignity. However, practical applications of aqueous batteries are plagued by water's intrinsically narrow electrochemical stability window, which results in low energy density. In this perspective article, we review several strategies to broaden the electrochemical window of aqueous electrolytes and realize high-energy aqueous batteries. Specifically, we highlight our recent findings on stabilizing aqueous Li storage electrochemistry using a deuterium dioxide-based aqueous electrolyte, which shows significant hydrogen isotope effects that trigger a wider electrochemical window and inhibit detrimental parasitic processes.

A robust three-dimensional (3D) interconnected sulfur host and a polysulfide-proof interlayer are key components in high-performance Li–S batteries. Herein, cellulose-based 3D hierarchical porous carbon (HPC) and two-dimensional (2D) lamellar porous carbon (LPC) are employed as the sulfur host and polysulfide-proof interlayer, respectively, for a Li–S battery. The 3D HPC displays a cross-linked macroporous structure, which allows high sulfur loading and restriction capability and provides unobstructed electrolyte diffusion channels. With a stackable carbon sheet of 2D LPC that has a large plane view size and is ultrathin and porous, the LPC-coated separator effectively inhibits polysulfides. An optimized combination of the HPC and LPC yields an electrode structure that effectively protects the lithium anode against corrosion by polysulfides, giving the cell a high capacity of 1339.4 mAh g−1 and high stability, with a capacity decay rate of 0.021% per cycle at 0.2C. This work provides a new understanding of biomaterials and offers a novel strategy to improve the performance of Li–S batteries for practical applications.

Low-dimensional luminescent lead-free metal halides have received substantial attention due to their unique optoelectronic properties. Among them, zero-dimensional (0D) manganese (II)-based metal halides with negligible self-absorption have emerged as potential candidates in X-ray scintillators. Herein, we for the first time report a novel lead-free (TBA)2MnBr4 single crystal synthesized via a facile solvent evaporation method. In this crystal, [MnBr4]2− units are isolated by large TBA+ organic cations, resulting in a unique 0D structure. The prepared manganese-based crystals exhibit a bright-green emission centered at 512 ​nm with a high photoluminescence quantum yield (PLQY) of 93.76% at room temperature, originating from the 4T1–6A1 transition of Mn2+. Apart from their outstanding optical performance, the crystals also show excellent stability and can maintain 94.4% of the initial PLQY even after being stored in air for 90 days. Flexible (TBA)2MnBr4 films prepared as X-ray imaging scintillators exhibit a low detection limit of 63.3 nGyair/s, a high light yield of 68000 ​ph/MeV, and a high spatial resolution of 15.4 ​lp/mm. Thus, this work not only enriches the family of lead-free metal halides but also expands the application of manganese (II)-based halides in flexible X-ray scintillators.

SiO-based materials represent a promising class of anodes for lithium-ion batteries (LIBs), with a high theoretical capacity and appropriate and safe Li-insertion potential. However, SiO experiences a large volume change during the electrochemical reaction, low Li diffusivity, and low electron conductivity, resulting in degradation and low rate capability for LIBs. Here, we report on the rapid crafting of SiO–Sn2Fe@C composites via a one-step plasma milling process, leading to an alloy of Sn and Fe and in turn refining SiO and Sn2Fe into nanoparticles that are well dispersed in a nanosized, few-layer graphene matrix. The Sn and Fe nanoparticles generated during the first Li-insertion process form a stable network to improve Li diffusivity and electron conductivity. As an anode material, the SiO–Sn2Fe@C composite manifests high reversible capacities, superior cycling stability, and excellent rate capability. The capacity retention is found to be as high as 95% and 84% at the 100th and 300th cycles under 0.3 ​C. During rate capability testing at 3, 6, and 11 ​C, the capacity retentions are 71%, 60%, and 50%, respectively. This study highlights that this simple, one-step plasma milling strategy can further improve SiO-based anode materials for high-performance LIBs.

Layered oxide cathodes with high Ni content promise high energy density and competitive cost for Li-ion batteries (LIBs). However, Ni-rich cathodes suffer from irreversible interface reconstruction and undesirable cracking with severe performance degradation upon long-term operation, especially at elevated temperatures. Herein, we demonstrate in situ surface engineering of Ni-rich cathodes to construct a dual ion/electron-conductive NiTiO3 coating layer and Ti gradient doping (NC90–Ti@NTO) in parallel. The dual-modification synergy helps to build a thin, robust cathode–electrolyte interface with rapid Li-ion transport and enhanced reaction kinetics, and effectively prevents unfavorable crystalline phase transformation during long-term cycling under harsh environments. The optimized NC90–Ti@NTO delivers a high reversible capacity of 221.0 mAh g−1 at 0.1C and 158.9 mAh g−1 at 10C. Impressively, it exhibits a capacity retention of 88.4% at 25 ​°C after 500 cycles and 90.7% at 55 ​°C after 300 cycles in a pouch-type full battery. This finding provides viable clues for stabilizing the lattice and interfacial chemistry of Ni-rich cathodes to achieve durable LIBs with high energy density.

Electrochemical CO2 reduction is a typical surface-mediated reaction, with its reaction kinetics and product distributions largely dependent on the dynamic evolution of reactive species at the cathode–catholyte interface and on the resultant mass transport within the hydrodynamic boundary layer in the vicinity of the cathode. To resolve the complex local reaction environment of branching CO2 reduction pathways, we here present a differential electrochemical mass spectroscopic (DEMS) approach for Cu electrodes to investigate CO2 mass transport, the local concentration gradients of buffering anions, and the Cu surface topology effects on CO2 electrolysis selectivity at a temporal resolution of ∼400 ms. As a proof of concept, these tuning knobs were validated on an anion exchange membrane electrolyzer, which delivered a Faradaic efficiency of up to 40.4% and a partial current density of 121 mA cm–2 for CO2-to-C2H4 valorization. This methodology, which bridges the study of fundamental surface electrochemistry and the upgrading of practical electrolyzer performance, could be of general interest in helping to achieve a sustainable circular carbon economy.

Organic optoelectronic materials enable cutting-edge, low-cost organic photodiodes, including organic solar cells (OSCs) for energy conversion and organic photodetectors (OPDs) for image sensors. The bulk heterojunction (BHJ) structure, derived by blending donor and acceptor materials in a single solution, has dominated in the construction of active layer, but its morphological evolution during film formation poses a great challenge for obtaining an ideal nanoscale morphology to maximize exciton dissociation and minimize nongeminate recombination. Solution sequential deposition (SSD) can deliver favorable p–i–n vertical component distribution with abundant donor/acceptor interfaces and relatively neat donor and acceptor phases near electrodes, making it highly promising for excellent device performance and long-term stability. Focusing on the p–i–n structure, this review provides a systematic retrospect on regulating this morphology in SSD by summarizing solvent selection and additive strategies. These methods have been successfully implemented to achieve well-defined morphology in ternary OSCs, all-polymer solar cells, and OPDs. To provide a practical perspective, comparative studies of device stability with BHJ and SSD film are also discussed, and we review influential progress in blade-coating techniques and large-area modules to shed light on industrial production. Finally, challenging issues are outlined for further research toward eventual commercialization.

Although single-atom catalysts (SACs) have attracted enormous attention for their applications in the electrochemical reduction of CO2 (CO2RR) due to their extraordinary catalytic activity and well-defined active centers, neighboring effects and their influence on the electrochemical performance of SACs have not been well investigated. In this review, we present a summary of the neighboring effects on SACs for the CO2RR process, where the surrounding atoms not only induce electronic modulation of the metal atom but also participate in the CO2RR. Both theoretical and experimental studies have pointed out that the neighboring sites of the anchored metal center can provide second active/adsorption locations during the catalytic process, enhancing CO2RR performance tremendously. This review supplies advanced insights into the significant roles and impacts of neighboring effects on the catalytic process, which also benefit the development of advanced SACs to achieve efficient electrocatalysis.

Microenvironments of the catalytic center, which play a vital role in adjusting electrocatalytic CO2 reduction reaction (ECO2RR) activity, have received increasing attention during the past few years. However, controllable microenvironment construction and the effects of multi-microenvironment variations for improving ECO2RR performance remain unclear. Herein, we summarize the representative strategies for tuning the catalyst and local microenvironments to enhance ECO2RR selectivity and activity. The multifactor synergetic effects of microenvironment regulation for enhancing CO2 accessibility, stabilizing key intermediates, and improving the performance of ECO2RR catalysts are discussed in detail, as well as perspectives on the challenges when investigating ECO2RR microenvironments. We anticipate that the discussions in this review will inspire further research in microenvironment engineering to accelerate the development of the ECO2RR for practical application.

Sn-based materials are promising candidates for lithium storage but suffer generally from huge volume change during the (de)lithiation processes. Sn-organic materials with monodispersed Sn centers surrounded by lithium active ligands can alleviate the volume change of anode materials based on reversible (de)lithiation processes. However, the structural factors governing the kinetics of lithium storage and utilization efficiency of active sites are not well understood to date. Herein, we report three two-dimensional Sn-organic materials with enhanced lithium storage performance by manipulation of π-aromatic conjugation of the ligands. The increasing π-aromatic conjugation plays a key role in promoting efficient lithium storage, and the volume expansion during the (de)lithiation reaction is suppressed in these Sn-organic materials. This work reveals that the π-aromatic conjugation of the ligand is crucial for improving the kinetics of lithium storage and the utilization of active sites in metal-organic materials with minimised volume expansion.

The practical applications of lithium metal batteries are limited by uncontrolled dendrite growth during cycling. Herein, we propose a simple and scalable approach to stabilize lithium metal anodes using laser scribing technology to integratively design and construct a laser-induced graphene (LIG) with lithiophilic metal oxide nanoparticles. The porous LIG and lithiophilic MnOx nanoparticles effectively reduce the nucleation overpotential of Li and regulate uniform Li plating, while the array structure offers continuous and ultra-fast ion/electron transport channels, accelerating Li+ transport kinetics at high rate and high capacity. Consequently, the Li@MnOx@LIG-a anode exhibits superior rate capability of up to 40 mA cm−2 with low nucleation overpotential. It also can withstand ultra-high Li capacity to 20 mAh cm−2 without dendrite growth and stably cycle for 3000 h with 100% depth of discharge at 40 mA cm−2. More importantly, this technology can be expanded to other metal oxides for various metal batteries.

Understanding and tuning charge transport over a single molecule is a fundamental topic in molecular electronics. Single-molecule junctions composed of individual molecules attached to two electrodes are the most common components built for single-molecule charge transport studies. During the past two decades, rapid technical and theoretical advances in single-molecule junctions have increased our understanding of the conductance properties and functions of molecular devices. In this perspective article, we introduce the basic principles of charge transport in single-molecule junctions, then give an overview of recent progress in modulating single-molecule transport through external stimuli such as electric field and potential, light, mechanical force, heat, and chemical environment. Lastly, we discuss challenges and offer views on future developments in molecular electronics.