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Degraded LiCoO2 cathode from retired Li‐ion batteries is urgently required to be recycled in a greener way for economic and environmental considerations. The coarse metallurgy technologies for Li/Co extraction with massive CO2 emission and energy consumption cannot satisfy the requirements of carbon neutralization. Herein, it is proposed that direct regeneration of degraded LiCoO2 cathode could be realized via 9‐fluorenone‐mediated Li supplementation and follow‐up structural restoration. The 9‐fluorenone‐lithium reagent is elaborately selected to compensate for the missing Li+ into lattice with targeted stoichiometry owing to its compatible redox potential of 1.95 V versus Li+/Li, which is located just between the reversible intercalation (3.8 V) and irreversible conversion (1.2 V) potentials of LiCoO2 electrode. Then, thermal energy‐driven structure reorganization enables Li/Co atoms to occupy the right sites, accomplishing desirable structure healing within a short annealing time of 4 h. The regenerated LiCoO2 cathode exhibits comparable Li‐storage capability to commercial LiCoO2, benefiting from the non‐destructive direct regeneration technology. In addition, the regeneration route is regarded as environmentally (0.13 kg CO2 kg−1 cell) and economically (10.07 $ kg−1 cell) superior to conventional recycling routes based on life‐cycle analysis. The precise surgery on spent LiCoO2 cathode provides a promising solution for the forthcoming retirement rush of Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Interfacial modification is a key strategy for improving the performance of perovskite photovoltaic devices. While the modification of the top surface of the perovskite active layer is well established, engineering of the buried interface is highly challenging. Here, the spontaneous formation of a 1D/3D perovskite heterojunction at the buried interface of a perovskite active layer by incorporating choline acetate alongside the perovskite precursors is reported. Importantly, extensive spectroscopic and microscopic characterization and solid‐state nuclear magnetic resonance experiments demonstrate the formation of phase‐pure 1D and 3D domains. The 1D/3D junction results in a suppression of the defect states and an improved energetic level alignment at the buried interface, leading to a maximum power conversion efficiency of >24% when incorporated in inverted architecture perovskite solar cells. This work introduces a versatile approach to the modification of the buried interface of the perovskite active layer. [ABSTRACT FROM AUTHOR]

Photocatalytic N2 reduction to ammonia rises as a cost‐effective, environmentally benign, and efficient route to generate ammonia as a transportable/storable energy carrier and essential fertilizer. Recently, photocatalysts anchored with various atomically scattered active centers (ASACs), such as Ru, Fe, Au, Pt, Cu, Mo, and La, are extensively explored in photocatalytic N2‐to‐ammonia transformation. This review critically summarizes the current achievements in the synthesis of various photocatalyst supports (such as metal oxide, carbon nitride, metal‐organic framework, and covalent organic framework) anchored with the above‐mentioned ASACs for N2 reduction to form ammonia. The synthesis routes, structural/compositional characteristics, and performances of these ASACs anchored photocatalysts are summarized and introduced. Furthermore, the atomic‐scale relationship between the structure/composition and performance of these ASACs anchored photocatalysts is also introduced. The reaction mechanism including the reaction kinetics/thermodynamics, reaction pathways, and charge carrier kinetics, especially those revealed by various state‐of‐art characterization techniques, have been highlighted. This review also outlines the basic principles for the synthesis of novel photocatalysts aimed at ammonia evolution. Finally, the current challenges, opportunities, and future outlooks of ASACs anchored photocatalysts for ammonia evolution are introduced. [ABSTRACT FROM AUTHOR]

The ternary strategy has proven to be an effective method for improving the efficiency of organic solar cells (OSCs). However, designing and selecting the third component still pose challenges. In this study, this issue is addressed by focusing on the PBDB‐T:Y18‐F binary system and introducing a new, strong luminescent, asymmetric small‐molecule acceptor (SMA) called L8‐CBIC‐Cl, which shares a similar skeleton with Y18‐F. The similarity in molecular framework facilitates good compatibility between the two acceptors, resulting in the formation of an alloy‐like acceptor phase. Furthermore, the norbornenyl‐modified end group in L8‐CBIC‐Cl contributes to its strong luminescent properties, which in turn leads to a low non‐radiative energy loss and a high open‐circuit voltage. Consequently, the PBDB‐T:L8‐CBIC‐Cl:Y18‐F based ternary devices realize a high power conversion efficiency (PCE) up to 17.01%, which is higher than PBDB‐T:Y18‐F device (14.49%). Importantly, L8‐CBIC‐Cl exhibits a good universality as a guest acceptor in other three binary systems (D18:Y6, D18:BTP‐eC9‐4F, and D18:L8‐BO). The D18:L8‐BO:L8‐CBIC‐Cl device shows an impressive efficiency of 19%. The work demonstrates that employing SMA with a high PLQY and better miscibility with host acceptor as the third component has a great potential for developing high‐efficiency ternary OSCs. [ABSTRACT FROM AUTHOR]

The discovery of ductile Ag2(S, Se, Te) materials opens a new avenue toward high‐performance flexible/hetero‐shaped thermoelectrics. Specifically, the cubic‐structured materials are quite attractive by combining remarkable plasticity, decent thermoelectric figure of merit (zT), and no phase transition above room temperature. However, such materials are quite few and the understanding is inadequate on their mechanical and thermoelectric properties. Enlightened by the high‐entropy principles, a series of pseudo‐ternary Ag2S‐Ag2Se‐Ag2Te alloys is designed and comprehensive diagrams of composition‐structure‐plasticity‐zT are compiled. Subsequently, the compositional region for the cubic phase is outlined. As a high‐entropy example featuring with anion‐site alloying and disordered Ag ions, Ag2‐xS1/3Se1/3Te1/3 materials exhibit impressively large elongations of 60–97%, ultralow lattice thermal conductivities of ≈0.2 W m−1 K−1, and decent zT values of 0.45 at 300 K, 0.8 at 460 K. The materials can be readily rolled into thin foils, showing excellent flexibility. Finally, a six‐leg in‐plane device is fabricated, achieving an output voltage of 13.6 mV, a maximal power of 12.8 µW, and a power density of 14.3 W m−2 under the temperature difference of 30 K, much higher than the organic counterparts. This study largely enriches the members of cubic ductile inorganic materials for the applications in flexible and hetero‐shaped energy and electronic devices. [ABSTRACT FROM AUTHOR]

Tin‐based perovskite solar cells (TPSCs) have attracted significant research interest due to their exceptional optoelectronic properties and environmentally friendly characteristics. However, TPSCs with ideal bandgap suffer from substantial current losses, necessitating the development of innovative interface engineering strategies to enhance device performance. In this study, an unprecedented approach constructing charge transfer path is presented by a simple post‐growth treatment of 3‐Aminomethylbenzo[b]thiophene (3‐AMBTh) on the perovskite film. The selective reaction of 3‐AMBTh with exposed FA+ on the perovskite surface suppresses the formation of iodine vacancy defects, leading to a reduction in trap density. Additionally, the residual aromatic rings on the surface form an effective π–π stacking interaction system with subsequently deposited ICBA, facilitating enhanced charge transfer at the interface. By harnessing the potential of the charge transfer path, the TPSCs exhibit remarkable device efficiency of up to 14.53%, positioning them among the top‐performing TPSCs reported to date. [ABSTRACT FROM AUTHOR]

Designing textile‐based energy storage with both high electrochemical performance and available textile performance is crucial for developing smart textile. In this perspective, the concept of textile‐based energy storage and the viewpoint of balancing electrochemical performance and textile performance is proposed, which is paramount to establish high‐energy‐power density textile‐based energy storage devices; some key challenges are discussed in order to provide a framework on how textile materials and structures are employed in textile energy storage research; it further compiles and generalizes current findings in the fiber, yarn, and fabric‐type components/devices area and preliminary work in the manufactured and programmed textile‐based energy storage. The objective here is to establish a set of practical principles for commercial textile energy storage from textile perspective and describe in detail the scientific and technological breakthroughs that are shaping in energy storage area. [ABSTRACT FROM AUTHOR]

LaTiO2N is a promising narrow‐bandgap semiconductor photocatalyst that shows great promise for water redox reactions. However, its performance is often hindered by fast photocarrier recombination events. Herein, LaTiO2N mesoporous single crystals (MSCs) are successfully fabricated via a topotactic conversion route by using the Ruddlesden–Popper compound NaLaTiO4 as the precursor. The LaTiO2N MSCs are characterized by high crystallinity, abundant mesopores, no grain boundaries (GBs), and exposure of (010) and (101) crystal facets. A facet‐assisted photocarrier separation mechanism is identified for these LaTiO2N MSCs which contributes to the much better photocarrier separation than conventional counterparts. By loading proper cocatalysts, LaTiO2N MSCs serve as an efficient photocatalyst for water‐splitting half‐reactions and are capable of photocatalyzing overall water‐splitting reactions, delivering an impressive apparent quantum efficiency (AQE) as high as 65.07% at 420 ± 20 nm for O2‐evolution and a solar‐to‐hydrogen (STH) efficiency as high as 0.012% for solar‐driven overall water splitting. These findings not only highlight the grain‐boundary‐free MSCs with peculiar crystal‐facet exposure as highly active photocatalysts for particulate photocatalysis but also provide a rational design approach for developing efficient photocatalysts. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous calcium‐ion batteries (CIBs) are promising for reliable large‐scale energy storage. However, they face significant challenges, primarily stemming from suboptimal anodes, resulting in unfavorable voltage profiles, limited capacity, and diminished durability, all of which hinder the development of CIBs. Here, a covalent organic framework (PTHAT‐COF) featuring repeated pyrazine and pyridinamine units, employed as the anode material for aqueous CIBs, is introduced. This innovative approach results in a remarkably flat ultralow potential plateau ranging from −0.6 to −1.05 V (vs Ag/AgCl), attributed to the high level of the lowest unoccupied molecular orbital. Furthermore, the PTHAT‐COF anode exhibits outstanding rate performance (152.3 mAh g−1 @ 1 A g−1), exceptional long‐term cycling stability, and remarkable capacity retention (10 000 cycles with 89.9% retention). Mechanistic studies, including experimental and theoretical calculations, reveal that C═N active sites reversibly trap Ca2+ ions via chemisorption during the discharging/charging process. The PTHAT‐COF demonstrates exceptional structural stability throughout cycling. Finally, by pairing PTHAT‐COF with a high‐voltage manganese‐based Prussian blue cathode, a complete aqueous CIB with a voltage interval of 2.2 V is achieved, exhibiting extraordinary durability (10 000 cycles with 83.6% retention). This research illuminates the potential of organic anode materials in aqueous batteries to achieve higher battery voltages. [ABSTRACT FROM AUTHOR]

Using a screen‐printing techniques is thought to be a good candidate for simplified, cost‐effective, reliable, and scalable fabrication of fully printed perovskite solar cells (PSCs) for industrialization. Nevertheless, the screen‐printing of perovskite film has not been realized until recently. This group finished the work using ionic liquid methylamine acetate (MAAc) as pure solvent. However, the space‐confining effect during the perovskite crystallization in mesoporous impeded the escape of bottom MAAc molecules, which leads to the poor crystalline quality of the screen‐printed film. In this work, ionic liquid methylamine propionate (MAPa) with stronger coordination is introduced as a co‐solvent to promote the escape of MAAc molecules by forming the solvent volatilization channels in a confined mesoporous structure, which results in the complete MAAc volatilization and high filling degree of perovskite crystals inside the mesoporous structure. Also, MAPa promotes the vertical growth of perovskite crystals and coordinates with unbonded Pb2+ on the perovskite surface, leading to efficient charge transport and interfacial band alignment of the screen‐printed film. Finally, fully screen‐printed PSCs yields a champion power conversion efficiency (PCE) of ≈17%, which is the record value for fully screen‐printed PSCs. Moreover, the unencapsulated device shows robust operational stability that maintains >85.3% of initial PCE (25%RH and 25 °C) under continuous illumination at the maximum power point after 250 h. [ABSTRACT FROM AUTHOR]

The integration of solar‐driven interfacial evaporation and electricity co‐generation is considered a promising approach to simultaneously alleviate freshwater scarcity and the energy crisis. However, affected by intermittent solar irradiation/uncontrollable weather, the overall performance of solar‐driven evaporation in the real world is greatly reduced. Herein, inspired by antifreeze proteins in beetles that survive in extreme climates, all‐weather solar‐driven interfacial evaporators with a sandwich structure are designed. The top and bottom layers composed of MnO2‐modified cotton cloth are used for photothermal conversion and water transport, meanwhile, the middle layer made of a phase change microcapsule/hydrogel composite serves for heat storage and release. Under 1 kW m−2 irradiation, the evaporator exhibits a high evaporation rate of 2.67 kg m−2 h−1 and an efficiency of 89.5%. In the dark, the heat released from the phase change layer supports an evaporation rate of 0.43 kg m−2 h−1, 3.6 times that of pure water. Additionally, assembled with a thermoelectric module, the hybrid device achieves a stable output electricity power of 0.42 W m−2 under 1‐sun illumination and a prolonged output for 30 min in the dark. This work provides a novel approach for full‐time solar‐powered steam‐electricity co‐generation and a proof of concept for biomimetic steam generation/heat management integration. [ABSTRACT FROM AUTHOR]

As one of the most promising anodes of aqueous batteries, Zn metal faces uncontrollable side reactions and deleterious dendrite growth, which drastically compromise its cycle life and Coulombic efficiency (CE). To tackle these issues, a versatile electrolyte additive is reported that can regulate the solvation structure, adsorb on the Zn surface, and in situ generate a novel zincophilic‐microhydrophobic interphase to isolate the anode from the reactive water molecules. Benefiting from its triple effects on the water reactivity modulation, the Zn metal anode exhibits excellent reversibility with an ultra‐high average CE value of 99.92% at 5 mA cm−2 in the ZnSO4 electrolyte system, and the Zn||Zn symmetric cell with ethanesulfonamide additive achieves a long lifespan over 6000 h. The merits of ESA additives are further displayed in the Zn//MnO2 full cells and Zn ion hybrid capacitors, exhibiting excellent capacity retention of 81.60% at 5 C over 1000 cycles, and a 92.25% capacity retention over 50 000 cycles at 5 A g−1, respectively. What's more, the full cells exhibit outstanding stability of 100% capacity retention after 120 cycles at 0.1 C. This strategy shows a promising alternative for the further development of aqueous Zn metal batteries with low‐cost ZnSO4‐based electrolytes. [ABSTRACT FROM AUTHOR]

High‐boiling‐point solvents are considered to be decent solvents for the preparation of large‐area organic solar cells (OSCs) because of their wide processing window. However, the efficiency of OSCs processed by high‐boiling‐point solvents is still unsatisfactory. Herein, it is found that the agglomerate growth of nonfullerene acceptors into micrometer‐sized domains is the main reason for poor efficiency. A facile rapid molding process (RMP) scheme is proposed to solve this problem by adjusting the nucleation and growth behavior of acceptor molecules. RMP enables the blend films with interpenetrating networks and higher crystallinity, which is in favor of faster exciton separation and lower recombination losses. As a result, the power convention efficiency (PCE) is improved from 15.91% (reference) to 18.32% (RMP) for PL1:BTP‐eC9‐4F OSCs. To the best of the authors' knowledge, this is the champion efficiency of OSCs processed with high‐boiling‐point solvents. Meanwhile, RMP devices maintain 85% or 90% of the initial PCE after real day/night cycling in the air for over 2000 h or after continuous thermal aging at 85 °C in nitrogen for 500 h, respectively. [ABSTRACT FROM AUTHOR]

Urea electrolysis can convert urea from urea‐rich wastewater to hydrogen for environmental protection and sustainable energy production. However, the sluggish kinetics of urea oxidation reaction (UOR) requires valence‐variable sites that are generally active at high anodic overpotentials. Herein, a robust ceramic coating is constructed with coupled tungsten nitride (WN)/nickel carbide (Ni3C) nanoparticles to achieve valence‐stable catalytic sites with outstanding UOR performance. Various characterization results indicate strong interfacial electron transfer from WN to Ni3C in coupled nanoparticles, which enables reservation of Ni2+ sites without self‐oxidation during UOR, quite distinct from the kinetically slow Ni3+OOH‐catalyzed UOR pathway. Theoretical calculations show that the coupled effect in WN/Ni3C leads to enhanced electron transfer from catalytic sites to adsorbed urea, and W sites are thermodynamically favorable for UOR. This efficiently lowers the barrier of rate‐determining step (RDS: *CO‐N2 → *CO·OH), thus enabling fast UOR kinetics and a low potential of 1.336 V at 100 mA cm−2, which identifies this ceramic coating as one of the best UOR electrocatalysts. This work opens a new avenue for design of stable and active sites in ceramics coatings toward advanced electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Although the advances in organic solar cells (OSCs) have been considerable, their efficiency is still limited by recombination losses. Photogenerated electrons and holes are generally bound as localized excitons in organic semiconductors. The transition from excitons into free charges requires diffusion and dissociation processes, in which parasitic recombination losses exist. Reducing these losses is necessary for highly efficient OSCs. The crystallization behavior of the active layers can influence the efficiency of exciton diffusion and dissociation. In this work, different additives are delicately designed to control the crystallization behavior. It is found that the crystallization quality of active layers can be improved by controlling the aggregation of nonfullerene acceptors. The π–π stacking of blend films becomes compact, meanwhile, the crystallization in the vertical direction is more uniform. These are beneficial to the diffusion and dissociation of excitons. As a consequence, recombination losses are reduced and power convention efficiencies (PCEs) are improved significantly. Meanwhile, the general applicability of the additive is demonstrated in various organic photovoltaic systems, in which a PCE of 19.3% is achieved in D18:BTP‐eC9‐4F OSCs. This work provides a facile strategy to reduce the recombination losses of excitons for efficient devices. [ABSTRACT FROM AUTHOR]

Rational design/fabrication of high‐activity photocatalysts is of central importance to realize solar‐to‐chemical conversion for tackling worldwide energy/environmental issues. Hence, it is desirable to disclose the element/space/time‐resolved charge kinetics and surface species evolution of photocatalysts under realistic conditions using various in situ characterizations. Furthermore, the correlation of the above‐disclosed mechanisms with atomic‐scale compositions/structures of photocatalysts can further direct the atomic‐level design/synthesis of high‐performance photocatalysts. Herein, Ru atoms incorporated CdS quantum dots (QDs) are synthesized using an in situ hot‐injection route. The optimized Ru incorporated CdS QDs (Ru0.1) exhibit excellent photocatalytic evolution rates of H2O2 (8.78 mmol g−1 h−1) and benzaldehyde (11.70 mmol g−1 h−1), respectively. Four different in situ characterizations demonstrate that in realistic conditions, the incorporated Ru atoms with high oxidation state (+3) effectively attract photo‐generated electrons from bulk to the overall surface of Ru0.1; these directed electron flows also greatly facilitate the transfer of photo‐generated holes from bulk to surface of Ru0.1 via efficiently reducing electron‐hole recombination. in situ diffuse reflectance infrared Fourier transform spectroscopy, electron spin spectroscopy, and species‐trapping experiments further reveal three possible reaction pathways for H2O2 evolution. This work underscores the use of in situ characterizations to reveal the element/space/time‐resolved electrons/holes kinetics and surface‐species generation for photocatalysts in realistic conditions. [ABSTRACT FROM AUTHOR]

Flow batteries (FBs) are one of the most promising strategies for large‐scale energy storage, in which the flow rates of electrolytes are critical to the redox reaction efficiency. However, low‐power and energy‐efficient strategies to effectively monitor and adjust the flow rates of FBs are great challenges. Here, a liquid metal based thin‐film and self‐powered triboelectric sensor (LM‐TS) to monitor and adjust the real‐time electrolyte flow rates in FBs is developed. By integrating the LM‐TS with a peristaltic pump (flow rate control unit in FB), the flow rates of electrolytes can be converted into readable electrical output signals. Furthermore, a logical and a control module are adopted to adjust the flow rates of electrolytes automatically after receiving those electrical signals, which are available to guarantee the optimal working condition of FBs. Benefiting from the high conductivity and outstanding ductility of ultrathin LM film, the self‐powered LM‐TS is endowed with high sensitivity, short response time (9.1 ms), and remarkable cyclic stability (> 20000 cycles) without affecting the normal operation of FBs. This is the first prototype of self‐powered adjustment sensor for FBs, which is readily extended to scaled‐up FB equipment for intermediate trial and large‐scale energy‐storage demonstration. [ABSTRACT FROM AUTHOR]

The morphological features of the active layer has always been an important factor limiting the efficiency of organic solar cells (OSCs). Although halogen‐based additives capable of forming non‐covalent bonds with active molecules can effectively adjust the morphology of active layer, the inner mechanism of positional isomerization of additives on the crystallization kinetics of bulk heterojunction has been ignored, which hinders further development of this technique. Herein, a new additive‐assisted optimization strategy for high‐efficiency OSCs based on three positional isomeric additives is proposed, which have different sites for two bromine substituents on the benzene ring. The results demonstrate that symmetrically structured additives with the smallest dipole moment, the lowest steric hindrance and the most uniformly distributed electrostatic potential, can form more suitable non‐covalent interactions with the acceptor, resulting in more reasonable molecular spatial distribution and better π–π stacking behavior. For other non‐fullerene systems, the symmetrically structured additive also shows the best effect on optimizing molecular aggregation and stacking. This work provides guidance for screening and designing additives with excellent morphology improvement capability and is expected to have a profound influence on further increasing efficiency of OSCs without adopting the isomerization strategy for active molecules possessing complex conjugated backbones and branched chains. [ABSTRACT FROM AUTHOR]

Thin film solar cells on semitransparent substrates are attracting much attention due to new application scenarios including building‐integrated photovoltaics (BIPV). Environmentally‐benign element constituted and highly stable kesterite Cu2ZnSn(S,Se)4 (CZTSSe) thin film solar cells are ideal candidates for such applications. However, the efficiency of kesterite solar cells on semitransparent substrates is far behind that on opaque Mo‐based substrates. Here, fabrication of CZTSSe solar cells on fluorine‐doped tin oxide (FTO) substrates from molecular solution and how step‐by‐step absorber engineering improves device performance is reported. A power conversion efficiency of 7.02% is obtained when the absorber is fabricated on bare FTO, which is improved to 9.56% after adding a MoO3 interfacial layer. Investigations show the enhancement originates from the transformation of MoO3 to MoSe2 during film selenization which initiates crystallization at the back contact and at the same time prevents oversize grains at the absorber surface. Na‐doping and Ag alloying further facilitate grain growth and mitigate band tailing, resulting in a certified effective area efficiency of 11.43% with all device parameters comparable to that on an Mo‐substrate. This is the first time highly efficient kesterite solar cells are demonstrated on transparent electrodes, which opens up new opportunities for these earth‐abundant elements composed of thin film photovoltaics. [ABSTRACT FROM AUTHOR]

Many thermoelectric materials benefit from complex microstructures. Grain boundaries (GBs) in nanocrystalline thermoelectrics cause desirable reduction in the thermal conductivity by scattering phonons, but often lead to unwanted loss in the electrical conductivity by scattering charge carriers. Therefore, modifying GBs to suppress their electrical resistivity plays a pivotal role in the enhancement of thermoelectric performance, zT. In this work, different characteristics of GB phases in Ti‐doped NbFeSb half‐Heusler compounds are revealed using a combination of scanning transmission electron microscopy and atom probe tomography. The GB phases adopt a hexagonal close‐packed lattice, which is structurally distinct from the half‐Heusler grains. Enrichment of Fe is found at GBs in Nb0.95Ti0.05FeSb, but accumulation of Ti dopants at GBs in Nb0.80Ti0.20FeSb, correlating to the bad and good electrical conductivity of the respective GBs. Such resistive to conductive GB phase transition opens up new design space to decouple the intertwined electronic and phononic transport in thermoelectric materials. [ABSTRACT FROM AUTHOR]

Unreacted/excess lead iodide is considered to be the archcriminal for the rapid degradation of hybrid perovskite solar cells. Meanwhile, a high‐quality perovskite film with uniform and large grain size is the basis for high‐performance perovskite modules. Herein, a dual‐site molecular additive 4‐Aniline Sulfonic Acid (4A) is developed to regulate the unreacted/excess PbI2 and passivate defects through hydrogen bonding and intermolecular interactions between amino, and a sulfate groups and PbI2, respectively. Furthermore, the introduction of the 4A additive can induce perovskite seeds to grow uniformly on the substrate, yielding dense, uniform and defect‐less perovskite films with large grain sizes. This enables the fabrication of perovskite photovoltaics with a maximum power conversion efficiency of 24.09% (0.09 cm2) and 20.87% (16 cm2), respectively. This work demonstrated a new strategy to deposit high‐quality large‐scale perovskite films for photovoltaic modules. [ABSTRACT FROM AUTHOR]

Aqueous zinc batteries (AZBs) are promising energy storage devices owing to their high safety, low cost, and environmental friendliness. However, energy density improvement and lifespan prolongation of AZBs are impeded by the poor reversibility of Zn anodes. Instead of focusing on restraining the water activity that has been widely discussed, this work reports a unique strategy to eliminate the side reactions, which is the simultaneous regulation of cation and anion fluxes by microporous material. The as‐synthesized protective layer possesses an excellent sieving ability to repel sulfate infiltration by channel effect and via the electric field, and homogenizes Zn ion flux to achieve a dendrite‐free morphology, which is confirmed by the electrochemical and theoretical investigations. The protected anode exhibits a long lifespan (2400 h), deep Zn plating/stripping, and high current tolerance (100 mA cm−2). As a result, the full battery achieves a capacity retention of 76.4% after 7500 cycles, and in the anode‐free configuration, a high energy density of 192.8 Wh kg−1 is observed, which is more than 50 times that of a full battery with a Zn foil anode. By regulating the cations and anions simultaneously, the proposed strategy provides a low‐cost remedy to achieve the practical scale‐up of AZBs. [ABSTRACT FROM AUTHOR]

To implement the growing requirement for higher energy density all‐solid‐state lithium batteries (ASSLBs), further increasing the working voltage of LiCoO2 (LCO) is a key to breaking through the bottleneck. However, LiCoO2 severe structural degradation and side reactions at the cathode interface obstruct the development of high‐voltage sulfide‐based ASSLBs (≥4.5 V). Herein, a nano‐metric Li1.175Nb0.645Ti0.4O3 (LNTO) coated LCO cathode where microscopic Ti and Nb segregation at the interface during cycling potentially stabilizes the cathode lattice, and minimizes side reactions, simultaneously, is designed. Advanced transmission electron microscopy reveals that the stable spinel phase minimizes the micro stress at the cathode interface, avoids structure fragmentation, and hence significantly enhances the long‐term cyclic stability of LNTO@LCO @ 4.5 V. Moreover, the differential phase contrast scanning transmission electron microscopy (DPC‐STEM) visualizes the nano‐interlayer LNTO to boost Li+ migration at the cathode interface. Electrochemical impedance spectroscopy (EIS) reveals that sulfide‐based cells with the LNTO nano‐layer effectively reduce the interfacial resistance to 140 Ω compared to LiNbO3 (235 Ω) over 100 cycles. Therefore, 4.5 V sulfide‐based ASSLBs offer gratifying long‐cycle stability (0.5 C for 1000 cycles, 88.6%), better specific capacity, and rate performance (179.8 mAh g–1 at 0.1 C, 97 mAh g–1 at 2 C). [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides are a promising and extremely pivotal class of electrocatalysts with potential applications in alkaline hydrogen evolution reaction (HER), especially, molybdenum diselenide. Although the exposed edge sites are generally considered to be the active sites of MoSe2 for HER, an intrinsic behavior (surface species evolution, structure/morphology conversion, stability) of MoSe2 electrode itself was not unveiled. Herein, the origin of MoSe2‐electrocatalyzed HER activity monitored by the quasi‐operando XPS and in situ Raman spectroscopy is presented. The findings clearly show dynamic evolution of both Mo and Se species on MoSe2 electrode surface for promoting HER activity and maintaining long‐term catalytic stability and reveal an electro‐oxidative dissolution and re‐adsorption mechanism. Theoretical calculations also corroborate these results. As expected, the addition of single or mixed MoO42− and SeO32− to the electrolyte of nickel foam directly verifies the critical role of surface‐adsorbed Mo and Se species for boosting HER activity and stability. Additionally, the oxidative dissolution of Se on NixSey electrode surface during HER is also observed, revealing the universality of oxidative dissolution of Se in transition metal selenides. This study provides a unique insight into the species evolution and surface structure transformation mechanism and activity improved origin of materials during the electroreduction process. [ABSTRACT FROM AUTHOR]

The aggravating extreme climate changes and natural disasters stimulate the exploration of low‐carbon/zero‐carbon alternatives to traditional carbon‐based fossil fuels. Solar‐to‐hydrogen (STH) transformation is considered as appealing route to convert renewable solar energy into carbon‐free hydrogen. Restricted by the low efficiency and high cost of noble metal cocatalysts, high‐performance and cost‐effective photocatalysts are required to realize the realistic STH transformation. Herein, the 2D FePS3 (FPS) nanosheets anchored with TiO2 nanoparticles (TiO2/FePS3) are synthesized and tested for the photocatalytic hydrogen evolution reaction. With the integration of FPS, the photocatalytic H2‐evolution rate on TiO2/FePS3 is radically increased by ≈1686%, much faster than that of TiO2 alone. The origin of the greatly raised activity is revealed by theoretical calculations and various advanced characterizations, such as transient‐state photoluminescence spectroscopy/surface photovoltage spectroscopy, in situ atomic force microscopy combined with Kelvin probe force microscopy (AFM‐KPFM), in situ X‐ray photoelectron spectroscopy (XPS), and synchrotron‐based X‐ray absorption near edge structure. Especially, the in situ AFM‐KPFM and in situ XPS together confirm the electron transport pathway in TiO2/FePS3 with light illumination, unveiling the efficient separation/transfer of charge carrier in TiO2/FePS3 step‐scheme heterojunction. This work sheds light on designing and fabricating novel 2D material‐based S‐scheme heterojunctions in photocatalysis. [ABSTRACT FROM AUTHOR]

The main reason for large energy loss in all‐inorganic perovskites is ascribed to the slow nucleation and fast crystallization of all‐inorganic perovskite films. Herein, a manipulating strategy is demonstrated to simultaneously realize rapid nucleation and slow crystal growth of CsPbI3 perovskite films by employing solvent molecular sieves in the antisolvent. First, the antisolvent treatment of mixed chlorobenzene and ethyl alcohol can induce the instantaneous supersaturation of perovskites to achieve rapid nucleation. Subsequently, the molecular layer of phthalimide (2‐N) molecules on the perovskite surface can be used as solvent molecular sieves to precisely control the evaporation of the solvent through molecule–solvent interactions. In addition, the molecules remaining on the surface can also effectively passivate the surface defects and improve the device performance. By this strategy, a synchronous regulation of rapid nucleation and slow crystal growth of perovskite films is realized for the first time. As a result, the CsPbI3 film with 2‐N treatment presents high‐quality crystallinity with large grains and less defects. The champion device exhibits an outdoor power conversion efficiency (PCE) up to 20.14% under AM1.5G illumination, and an indoor PCE up to 40.07% (Pout:133.9 µW cm–2) under a commonly used light‐emitting diode light source (2956 K, 1062 lux). [ABSTRACT FROM AUTHOR]

Fuel cell technology is a clean way of generating energy and should enable carbon neutrality. However, although traditional proton exchange membrane fuel cells (PEMFCs) have made a commercial impact, their high cost hinders their wider adoption. Fuel cells that use anion exchange membranes (AEMs) are a promising alternative to PEMFCs, as they can achieve the same performance at a lower cost. In this Perspective, recent trends in the fabrication of polymer‐based high‐performance AEMs are highlighted and future directions are identified. Since ensuring the durability of polymers in strong alkaline conditions is the most critical issue in the development of AEM fuel cells, strategies for the formation of polymers with chemical stability, mechanical stability, and ionic conductivity are primarily focused on. Successes in polymer design are expected to inaugurate the next generation of AEMs and trigger a fresh wave of innovation, leading to the development of long‐lasting fuel cells that reduce carbon emissions and facilitate sustainable development. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) are regarded as promising next‐generation energy storage systems owing to their remarkable theoretical energy density (2600 Wh kg‐1) and low cost. However, sluggish electrochemical kinetics, lithium polysulfides (LiPS) shuttling, and uncontrollable Li dendrite growth seriously hamper the commercial application of LSBs. Herein, dual‐functional 3D interconnected free‐standing fibers embedded with TiO2‐TiN heterostructures as an advanced skeleton are designed for concurrently regulating both the sulfur cathode (S/hollow TiO2‐TiN) and Li anode (Li/solid TiO2‐TiN). As a cathode skeleton, the hollow TiO2‐TiN fibers afford synergistic functions of chemical anchoring, physical confinement, and excellent electrocatalysis for LiPS. Meanwhile, the multifunctional skeleton with remarkable lithiophilicity and high conductivity can accomplish uniform Li deposition and homogeneous Li ion flux for inhibiting the growth of dendrites. Benefiting from these advantages, the full battery (S/hollow TiO2‐TiN || Li/solid TiO2‐TiN) exhibits excellent electrochemical performance, including high cycling stability (988.8 mAh g−1 after 200 cycles at 0.5 C) and impressive rate properties (639.3 mAh g−1 at 2 C). This work inaugurates a novel strategy from experimental and theoretical aspects for fabricating LSBs with robust electrochemical performance. [ABSTRACT FROM AUTHOR]

The vanadium‐supramolecules and their derivatives are in high demand because of their huge potential applications in various fields, especially as electrodes for supercapacitors and batteries. However, the complex synthesis process is still a significant challenge. Furthermore, for these self‐assembly processes, the early reaction stages, intermediates, and details of reaction kinetics are still unknown. Here, an efficient approach of rapid cooling for large‐scale fabrication of melamine‐ammonium metavanadate (C3H6N6‐NH4VO3) supramolecular nanoribbons is reported, and the corresponding nucleation and growth process are visualized by using an in situ polarizing microscope. The thermally induced nucleation takes place within tens of seconds, and once the nucleus is formed, C3H6N6 and NH4VO3 begin to assemble into nanoribbons under thermal control and grow epitaxial around the already‐formed nuclei. The growth process is much slower than the nucleation, until all small molecules are consumed. Rapid heat induction (rapid cooling) and shear force induction (stirring) help to form a uniform and wider 2D sheet rather than fibers or ribbons. After pyrolysis, the vanadium‐supramolecules derived vanadium nitride (VN)/carbon nanoribbons present a mesoporous structure, which endows the VN/carbon with high capacitance of 266.3 F g−1 at 0.5 A g−1. In addition, the relationship between various structures and their properties is systematically investigated. [ABSTRACT FROM AUTHOR]

Li‐rich Mn‐based layered oxides are regarded as the most promising cathode materials for advanced lithium‐ion batteries with energy density as high as 400 Wh kg−1. However, decline of capacity and discharge potential derived from phase transformation during cycling is still an obstacle for practical utilization of Li‐rich cathode materials. Undoubtedly, an in‐depth understanding origin and evolution of the phase transformation from bottom to top is crucial to solve the problem finally. Herein, the recent representative progress on Li‐rich cathode materials from top to bottom is summarized: starting from relationship between dimensions and performance, to evolution of phase transformation, finally to participation of anions during charge–discharge cycling. It systematically shows what happens in the different microscopic levels and how these phenomena relate to cycling of Li‐rich cathode materials with the help of emerging state‐of‐the‐art characterization techniques. On the basis of this progress, it is proposed that rational structural design can fully play its role to build high‐performance energy storage materials and enhance structural stability. [ABSTRACT FROM AUTHOR]

Tin‐based perovskites show great potential in photovoltaic applications, and the development of the corresponding solar cells (PSCs) has made exciting progress during the past few years. However, owing to the high Lewis acidity and easy oxidation of Sn2+, Sn‐based perovskite films suffer from fast crystallization and easy formation of vacancy defects with low activation energy during the solution film‐forming process, resulting in poor film quality and inferior device performance. Therefore, an in‐depth understanding and rational control of film‐forming dynamics of Sn‐based perovskites is essential to improve the photovoltaic performance of their PSCs. In this review, the state‐of‐the‐art developments in crystallization dynamics control for Sn‐based perovskites and their impact on the photovoltaic performance of PSCs are systematically summarized. The review begins with the introduction of fundamentals and key difficulties for the control of the crystallization process of Sn‐based perovskites. Then, the advanced strategies that focus on regulating the crystallization process of Sn‐based perovskite films are comprehensively reviewed, including solvent engineering, additive engineering, cation engineering, and film‐forming technique engineering. Finally, future perspectives and research directions, regarding the smart control of crystallization dynamics of Sn‐based perovskite film, are discussed towards high‐performance and stable Sn‐based PSCs. [ABSTRACT FROM AUTHOR]

Epitaxial strain has been shown to produce dramatic changes to the orbital structure in transition metal perovskite oxides and, in turn, the rate of oxygen electrocatalysis therein. Here, epitaxial strain is used to investigate the relationship between surface electronic structure and oxygen electrocatalysis in prototypical fuel cell cathode systems. Combining high‐temperature electrical‐conductivity‐relaxation studies and synchrotron‐based X‐ray absorption spectroscopy studies of La0.5Sr0.5CoO3 and La0.8Sr0.2Co0.2Fe0.8O3 thin films under varying degrees of epitaxial strain reveals a strong correlation between orbital structure and catalysis rates. In both systems, films under biaxial tensile strain simultaneously exhibit the fastest reaction kinetics and lowest electron occupation in the dz2 orbitals. These results are discussed in the context of broader chemical trends and electronic descriptors are proposed for oxygen electrocatalysis in transition metal perovskite oxides. [ABSTRACT FROM AUTHOR]

The discovery of solid‐phase, inexpensive transition‐metal‐based water oxidation catalysts is a central goal for renewable energy, and has led to a general consensus that a partially populated metal eg d‐electronic state is desirable, leading to favorable catalysis for certain elements in specific oxidation states. In manganese systems, the key species is manganese(III), whose high‐spin d4 electronic configuration places an unpaired electron in the eg orbital, which is postulated to contribute to electronic and structural features that support catalysis. Based on density functional theory calculations, it is predicted that electron transfer would be facilitated by a catalyst with alternating low‐ and high‐MnIII‐content sheets, which positions neighboring band edges in closer energetic proximity. The preparation of such catalysts is demonstrated for the first time and it is shown that the catalytic activity is maximized in these systems over more uniform, but more MnIII‐rich systems. The best catalyst possesses alternating high‐and low‐average oxidation state sheets with interlayer Cs+ ions, and has an overpotential of 450 mV at 10 mA, which represents an improvement of 250 mV over the best unmodified synthetic potassium birnessites. Using scanning tunneling spectroscopy, bandgap modulations consistent with the theoretically predicted band edge shifts are detected. [ABSTRACT FROM AUTHOR]

The inefficient charge separation and lack of active sites have been regarded as the main obstacles limiting the CO2 photoreduction efficiency. It is highly desirable but challenging to create a local polarization field to accelerate charge separation and build reactive sites for CO2 reduction dynamics. Herein, atomic level bismuth‐oxygen vacancy pairs are engineered into Bi24O31Br10 (BOB) atomic layers to create a local polarization field. It facilitates photogenerated electrons to migrate from BOB to vacancy pair sites and favors the activation of CO2 molecules. Simultaneously, it works as reactive sites to tune the non‐covalent interaction of intermediates and optimizes the reaction process. The vacancy pairs tuned surface atomic structures enable the formation of a highly stable Bi−C−O−Bi intermediate state and consecutive Bi−C−O intermediate, thus changing the rate‐determining step from CO* formation to COOH* formation. Benefiting from these features, the VBiO‐BOB delivers a 20.9‐fold CO2 photoreduction activity enhancement relative to highly crystalline BOB in pure water with highly stability. This work provides new insights for the design of a vacancy pair to create local polarization and tune the non‐covalent interaction. [ABSTRACT FROM AUTHOR]

Electrocatalytic oxidative upgrading of organic molecules is a promising alternative process to water oxidation for clean hydrogen production. Yet, its underlying mechanism is still not fully understood, and suitable low‐cost electrocatalysts with good product selectivity and activity are still sought after. Here, an active NiFeOx‐based catalyst is reported on as a general platform for the electro‐oxidative upgrading of organic molecules through oxygenation and dehydrogenation, with hydrogen coproduction. Detailed mechanistic studies unveil that C–H bond oxidation (with a bond dissociation energy BDEC–H of ≈88–96 kcal mol−1) is involved in the rate‐limiting step, which differs significantly from the oxygen evolution reaction mechanism. These findings show that the oxidation efficacy is linearly correlated with the BDEC–H of the molecule. Thus, the catalyst can be used as a general platform for large‐scale electro‐oxidation of various substrates through oxygenation and dehydrogenation at high current density (25 mA cm−2), with a good Faradaic yield. The platform's generality is further demonstrated by the selective oxidation of 5‐(hydroxymethyl)furfural into 2,5‐furandicarboxylic acid with good efficiency. [ABSTRACT FROM AUTHOR]

State‐of‐the‐art, high‐performance formamidinium‐lead‐iodide‐based (FAPbI3‐based) perovskite photovoltaics are mainly prepared by one‐step antisolvent dripping deposition or two‐step sequential fabrication methods. Compared with the one‐step deposition, the two‐step fabricated perovskite films tend to grow columnar perovskite grains vertically which is easier for carrier extraction and transportation. Herein, the concept of formamidinium methylammonium cesium based ternary‐cation two‐step sequential deposition method is put forward by incorporating cesium acetate (CsAc) into a lead iodide precursor, which generates CsPbI3 crystal nuclei improving the further perovskite crystallization. When the formamidinium/methylammonium‐based organic amine salts solution is spin coated on the PbI2 substrate, the acetate moves upward and induces perovskite orientational and uniform crystallization, which can go a step further for the vertical columnar grains achieving fewer defects and higher photovoltaic efficiency. The champion outdoor power conversion efficiency of the modified device under AM 1.5G reaches 21.50% and its indoor efficiency at 1000 lux reaches 40.99%. This work paves the way for further exploring ternary‐cation two‐step sequential deposition methods to prepare high‐performance perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Thin‐film deposition by thermal evaporation offers many advantages, yet in the field of perovskite photovoltaics solution‐processed devices significantly outperform those fabricated by thermal evaporation. Here, high‐quality γ‐CsPbI3 perovskite layers by coevaporation of PbI2 and CsI with a small amount of phenylethylammonium iodide (PEAI) are deposited. It is demonstrated that the addition of PEAI into the perovskite layers leads to a preferred crystal orientation and a far improved microstructure, with columnar domains that protrude throughout the film's thickness. This is accompanied by a reduced density of defects as evidenced by the increase in photoluminescence and decrease in Urbach energy as compared to reference CsPbI3 films. Photovoltaic devices based on the PEAI containing perovskite layers reach up to 15% in power conversion efficiency, thus surpassing not only the performance of reference CsPbI3 devices, but also that of most solution‐processed PEAI containing inorganic CsPbX3 (X = Cl, Br, I) perovskite solar cells. Importantly, encapsulated thermally evaporated perovskite devices maintain their performance for over 215 days, demonstrating the stabilizing effect of PEAI on thermally evaporated CsPbI3. [ABSTRACT FROM AUTHOR]

Deformable thermoelectrics have great potential in self‐powered flexible or hetero‐shaped electronics. The exceptional room‐temperature plasticity recently discovered in several inorganic semiconductors makes it possible to develop new thermoelectric (TE) materials with both high performance and intrinsic deformability. Nonetheless, all the known plastic or ductile TE materials are n‐type semiconductors. It is urgent to explore p‐type counterparts for device design and fabrication. In this study, the first p‐type plastic inorganic TE material is reported. Via alloying Cu in n‐type plastic Ag2S0.7Se0.3 to modulate the charged crystal defects, (Ag1−xCux)2S0.7Se0.3 (x = 0.7–0.8) can simultaneously realize good plasticity and p‐type conduction. Particularly, (Ag0.2Cu0.8)2S0.7Se0.3 with a hexagonal structure shows a maximum zT of 0.42 at 800 K. Via the introduction of Cu deficiencies, the good plasticity is well maintained while the maximum zT is greatly enhanced to 0.95 at 800 K, a record‐high value for plastic TE materials. This study is expected to accelerate the development of plastic TE semiconductors and full‐inorganic deformable TE devices for the application in hetero‐shaped power generators. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) feature rich chemistry, ordered micro‐/mesoporous structure and uniformly distributed active sites, offering great scope for electrochemical energy storage (EES) applications. Given the particular importance of porosity for charge transport and catalysis, a critical assessment of its design, formation, and engineering is needed for the development and optimization of EES devices. Such efforts can be realized via the design of reticular chemistry, multiscale pore engineering, synthesis methodologies, and postsynthesis treatment, which remarkably expand the scope of applications. By imparting conductive backbones, guest compounds, and/or redox‐active centers, MOFs and their derivatives have been heavily explored for EES in the last decade. To improve the design of MOF‐based materials for EES, the strategies of pore architecturing of MOFs and their derivatives are systematically analyzed and their applications reviewed for supercapacitors and metal‐ion batteries. Potential challenges and future opportunities are also discussed to guide future development. [ABSTRACT FROM AUTHOR]

The combination of ammonia fuel and proton-conducting fuel cells (PCFCs) technology may provide an ideal clean energy system for the future, considering matured NH3 synthesis technology and transportation and storage infrastructure, the high energy density of NH3, and the high efficiency of fuel cells. However, poor catalytic activity of the anode for NH3 decomposition, quick performance degradation due to the ammonia induced nickel coarsening, difficult sintering, and insufficient proton conductivity of electrolytes are the main challenges for stable and high-power generation from ammonia-fueled PCFCs. Herein, a new Ba(Zr0.1Ce0.7Y0.1Yb0.1)0.95Pd0.05O3-δ perovskite is reported as a key anode component and electrolyte, which demonstrates multifunctionalities and tackles most challenges of conventional PCFCs. The incorporation of a small amount of Pd boosts catalytic activity of the nickel-perovskite cermet anode for NH3 decomposition and increases proton conductivity from the creation of B-site cation deficiency and electrolyte sintering. The corresponding thin-film electrolyte PCFC delivers a maximum power density of 724 mW cm-2 at 650 °C operated on NH3, much higher than the similar cell without Pd incorporation (450 mW cm-2). Furthermore, no apparent performance decay is observed for the cell operated at 550 °C in H2 and NH3 for 350 h, making it highly promising for practical applications. [ABSTRACT FROM AUTHOR]

Ferrous sulfides with the high theoretic capacity are the promising anode for sodium ion batteries. However, capacity fading and inferior rate capability still hinder their practical application. In this work, Na‐doped Fe7S8 microrods with cationic vacancies and weakened Fe─S bond are constructed through a facile and scalable sulfurized route. The experimental results combined with theoretical analysis thoroughly reveal the generation of Fe vacancies and weakened Fe─S bond strength induced by sodium doping, which modulates the energy band structure of Na‐doped Fe7S8, provides more active sites, and accelerates the sodiation/desodiation reaction kinetics, simultaneously. Moreover, the pre‐doping sodium delivers a strong guiding effect on the formation of thin and stable solid electrolyte interface films. As the result, the optimal sample exhibits the excellent sodium storage performance, including the high and stable reversible capacity (674 mAh g−1 after 200 cycles at 0.5 A g−1 and 503 mAh g−1 after 1500 cycles at 10 A g−1), superior rate capability, and increased initial coulombic efficiency. Furthermore, the full cell paired with commercial Na3V2(PO4)3 also displays the outstanding cyclic stability with 95.9% capacity retention at 0.5 A g−1 after 100 cycles. [ABSTRACT FROM AUTHOR]

Perovskites (ABX3) are promising oxygen evolution reaction (OER) catalysts for their highly intrinsic activity. The in‐depth understanding and the adjustment of dynamic reconstruction of active phases for perovskites in OER are still a daunting challenge. Here, a refined A‐site management strategy is proposed for perovskite oxides, which facilitates the surface reconstruction of the B‐site element based active phase to enhance the OER performance. Electrocatalyst LaNiO3 displays a dynamic reconstruction feature during OER with the growth of a self‐assembled NiOOH active layer, based on the in situ electrochemical Raman technology. Precise A‐site Ce doping lowers the reconstruction potential for the active phase and the dynamic structure–activity correlation is well established. Theoretical calculations demonstrate that A‐site Ce substitution upshifts the O 2p level for greater structural flexibility with optimized oxygen vacancy content, thereby activating the B‐site atom and promoting the active phase reconstruction. These results suggest that A‐site management prompts the B‐site element based active phase dynamic reconstruction via engineered X‐site content as a bridge. Therefore, indicating the strong correlation of each‐site component in perovskite oxides during OER and deepening the understanding of the fundamental processes of the structural transformation and further benefiting the accurate design of high‐efficiency perovskite OER electrocatalysts. [ABSTRACT FROM AUTHOR]

A rechargeable hybrid zinc battery is developed for reaching high power density and high energy density simultaneously by introducing an alkaline Zn–transition metal compound (Zn–MX) battery function into a Zn–air battery. However, the conventional single‐layer electrode design cannot satisfy the requirements of both a hydrophilic interface for facilitating ionic transfer to maximize the Zn–MX battery function and a hydrophobic interface for promoting gas diffusion to maximize the Zn–air battery function. Here, a function‐separated design is proposed, which allocates the two battery functions to the two faces of the cathode. The electrode is composed of a hydrophobic MnS layer decorated with Ni–Co–S nanoclusters that allows for smooth gas diffusion and efficient oxygen electrocatalysis and a hydrophilic NixCo1−xS2 layer that favors fast ionic transfer and superior performance for energy storage. The battery with the function‐separated electrode shows a high short‐term discharge voltage of ≈1.7 V, an excellent high‐rate galvanostatic discharge–charge with a power density up to 153 mW cm−2 at 100 mA cm−2, a good round‐trip efficiency of 75% at 5 mA cm−2, and a robust cycling stability for 330 h with an excellent voltage gap of ≈0.7 V at 5 mA cm−2. [ABSTRACT FROM AUTHOR]

Various types of sodium manganese oxides are promising cathode materials for sodium storage systems. One of the most considerable advantages of this family of materials is their widespread natural abundance. So far, only a few host candidates have been reported and there is a need to develop new materials with improved practical electrochemical performance. Here, P2‐type Al/F‐doped sodium manganese oxide as well as its unique sodium storage mechanism is demonstrated by a combination of electrochemical characterization, structural analyses from powder X‐ray diffraction (XRD) data, and 3D bond valence energy level calculations for the sodium diffusion pathways. The material exhibits a high reversible capacity of 164.3 mAh g−1 (0.3C rate) and capacity retention of 89.1% after 500 cycles (5C rate). The study clearly unravels the beneficial effect of the doping and the unique sodium intercalation mechanism devoid of the low diffusion O3 transformation. [ABSTRACT FROM AUTHOR]

Aqueous sodium‐ion batteries are expected to be low‐cost, safe, and environmentally friendly systems for large scale energy storage due to the abundance and low cost of sodium. However, only a few candidates have been reported for cathodes and there is a need to develop new practical host materials with improved electrochemical performance. Here, tunnel‐type, calcium‐doped, sodium manganese oxide is demonstrated as a novel cathode material, ultrafast rate capabilities and superior high‐rate cycling stability—98.8% capacity retention at the 1000th cycle—for aqueous sodium‐ion batteries. Advanced structural analysis of the Ca0.07Na0.26MnO2 material using X‐ray diffraction and ab initio calculations identify the calcium sites and indicate a plausible sodium diffusion mechanism. Calcium preferentially substitutes at the Na(1) sites among the three different types of Na sites. This substitution creates vacancies at the Na(2) and Na(3) sites. Calculations of the energy barrier for Na ion diffusion indicate that diffusion along the Na(2)‐to‐Na(2) and Na(2)‐to‐Na(3) pathways is the most feasible. These vacancies provide improved diffusion kinetics and show 43% capacity enhancement at 50 C‐rate. The results suggest that Ca0.07Na0.26MnO2 is a promising cathode material for aqueous sodium‐ion batteries, and provide an improved fundamental understanding of sodium storage mechanisms. [ABSTRACT FROM AUTHOR]

Rhombohedral NaZr2(PO4)3 is the prototype of all the NASICON‐type materials. The ionic diffusion in these rhombohedral NASICON materials is highly influenced by the ionic migration channels and the bottlenecks in the channels which have been extensively studied. However, no consensus is reached as to which one is the preferential ionic migration channel. Moreover, the relationships between the Na+ distribution over the multiple available sites, concerted migration, and diffusion properties remain elusive. Using ab initio molecular dynamics simulations, here it is shown that the Na+ ions tend to migrate through the Na1–Na3–Na2–Na3–Na1 channels rather than through the Na2–Na3–Na3–Na2 channels. There are two types of concerted migration mechanisms: two Na+ ions located at the adjacent Na1 and Na2 sites can migrate either in the same direction or at an angle. Both mechanisms exhibit relatively low migration barriers owing to the potential energy conversion during the Na+ ions migration process. Redistribution of Na+ ions from the most stable Na1 sites to Na2 on increasing Na+ total content further facilitates the concerted migration and promotes the Na+ ion mobility. The work establishes a connection between the Na+ concentration in rhombohedral NASICON materials and their diffusion properties. [ABSTRACT FROM AUTHOR]

Electron beam microscopy and related characterization techniques play an important role in revealing the microstructural, morphological, physical, and chemical information of halide perovskites and their impact on associated optoelectronic devices. However, electron beam irradiation usually causes damage to these beam‐sensitive materials, negatively impacting their device performance, and complicating this interpretation. In this article, the electron microscopy and spectroscopy techniques are reviewed that are crucial for the understanding of the crystallization and microstructure of halide perovskites. In addition, special attention is paid to assessing and mitigating the electron beam‐induced damage caused by these techniques. Since the halide perovskites are fragile, a protocol involving delicate control of both electron beam dose and dose rate, coupled with careful data analysis, is key to enable the acquisition of reliable structural and compositional information such as atomic‐resolution images, chemical elemental mapping and electron diffraction patterns. Limiting the electron beam dose is critical parameter enabling the characterization of various halide perovskites. Novel methods to unveil the mechanisms of device operation, including charge carrier generation, diffusion, and extraction are presented in scanning electron microscopy studies combined with electron‐beam‐induced current and cathodoluminescence mapping. Future opportunities for electron‐beam‐related characterizations of halide perovskites are also discussed. [ABSTRACT FROM AUTHOR]

Tunnel‐type sodium manganese oxide is a promising cathode material for aqueous/nonaqueous sodium‐ion batteries, however its storage mechanism is not fully understood, in part due to the complicated sodium intercalation process. In addition, low cyclability due to manganese dissolution has limited its practical application in rechargeable batteries. Here, the intricate sodium intercalation mechanism of Na0.44MnO2 is revealed by combination of electrochemical characterization, structure determination from powder X‐ray diffraction data, 3D bond valence difference maps, and barrier‐energy calculations of the sodium diffusion. NaI is proposed as an important electrolyte solution additive. It is shown to form a thin, beneficial, and durable cathode surface film that prevents manganese dissolution. The addition of 0.01 m NaI to electrolyte solutions based on alkyl carbonate solvents and NaClO4 greatly improves the cycling efficiency, raising the capacity retention from 86% to 96% after 600 cycles. This study determines the core aspects of the sodium intercalation mechanism in tunnel‐type sodium manganese oxide and shows how it can serve as a durable cathode material for rechargeable Na batteries. [ABSTRACT FROM AUTHOR]

The advent of noble metal aerogels (NMAs), that feature the high catalytic activity of noble metals and unique structural attributes of aerogels, has stimulated research on a new class of outstanding electrocatalysts. However, limited by the available compositions, the explored electrocatalytic reactions on NMAs are highly restricted and certain important electrochemical processes have not been investigated. Here, an effective gelation approach is demonstrated by using a strong salting‐out agent (i.e., NH4F), thereby expanding the composition of NMAs to various multimetallic systems and providing a platform to investigate composition‐dependent electrocatalytic performance of NMAs. Combining structural features of aerogels and optimized chemical compositions, the Au–Pt and Au–Rh aerogel catalysts manifest remarkable pH‐universal (pH = 0–14) performance surpassing commercial Pt/C and many other nanoparticle (NP)‐based catalysts in the electrocatalytic oxygen reduction reaction, hydrogen evolution reaction, and water splitting, displaying enormous potential for the electrochemical hydrogen production, fuel cells, etc. [ABSTRACT FROM AUTHOR]

Noble metals, despite their expensiveness, display irreplaceable roles in widespread fields. To acquire novel physicochemical properties and boost the performance‐to‐price ratio for practical applications, one core direction is to engineer noble metals into nanostructured porous networks. Noble metal foams (NMFs), featuring self‐supported, 3D interconnected networks structured from noble‐metal‐based building blocks, have drawn tremendous attention in the last two decades. Inheriting structural traits of foams and physicochemical properties of noble metals, NMFs showcase a variety of interesting properties and impressive prospect in diverse fields, including electrocatalysis, heterogeneous catalysis, surface‐enhanced Raman scattering, sensing and actuation, etc. A number of NMFs have been created and versatile synthetic approaches have been developed. However, because of the innate limitation of specific methods and the insufficient understanding of formation mechanisms, flexible manipulation of compositions, structures, and corresponding properties of NMFs are still challenging. Thus, the correlations between composition/structure and properties are seldom established, retarding material design/optimization for specific applications. This review is devoted to a comprehensive introduction of NMFs ranging from synthesis to applications, with an emphasis on electrocatalysis. Challenges and opportunities are also included to guide possible research directions in this field and promote the interest of interdisciplinary scientists. [ABSTRACT FROM AUTHOR]