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Improving Pt catalytic activity and minimizing its usage as well as enhancing its stability is highly desirable for oxidation of methanol and ammonia in the field of electrocatalysis. Herein, the nanoporous Pt with coral‐like nanowires morphology/carbon fiber cloth electrocatalyst is reported, which is synthesized via a simple electrodeposition approach using phytantriol lyotropic liquid crystals as template. The obtained electrode with 3D coral‐like Pt nanowires architecture is composed of the orderly in situ grown Pt nanowires, and each individual Pt nanowire possesses a large number of nanopores. As expected, coral‐like Pt nanowires electrodes possess high electrochemical surface area of 43.1 m2 g‐1, almost twice that (25.4 m2 g‐1) of commercial Pt/C, and thus display superior catalytic activity of 343.1 mA mg‐1 and 72.0 mA mg‐1 toward methanol and ammonia oxidation, much higher than that of the commercial Pt/C (173.7 mA mg‐1 and 26.2 mA mg‐1), respectively. Additionally, the retention rates of oxidation peak current of coral‐like Pt nanowires electrode toward both methanol and ammonia oxidation after accelerated 100 cycles test achieve 82.1% and 85.6%, respectively, indicating the excellent stability of coral‐like Pt nanowires electrode. [ABSTRACT FROM AUTHOR]

To explore the application of neural network algorithm model in lung cancer imaging, and provide reference for the application and development of artificial neural network (ANN) algorithm model in lung cancer medical mirroring, so as to promote the development of ANN in this field. Meanwhile, it is hoped that the application of neural network algorithms in medical imaging can improve the survival rate and cure rate of lung cancer. In this study, an ANN algorithm model was selected to establish a lung cancer recognition model. After determining the lung cancer lesion area, the image segmentation algorithm was used to separately display the lung cancer lesion area, and a comparison experiment was designed to verify the accuracy of the model. ANNs were used to identify lung cancer, which can be concluded that the accuracy is 94.6%, the sensitivity is 95.7%, and the specificity is 93.5%. By combining image retrieval methods with lung cancer image segmentation algorithms, the lesion area of lung cancer can be clearly displayed. Therefore, the lung cancer image segmentation algorithm based on the neural network model has good recognition performance. This research can provide reference for the application of neural network algorithm model in the field of cancer diagnosis and treatment. [ABSTRACT FROM AUTHOR]

Abundant surface structural defects can endow electrocatalysts with extraordinary physical and chemical characteristics. Herein, metastable Pd nanoparticles (NPs) with abundant twin boundaries (TBs) and atomic steps (ASs) anchored on a carbon substrate (TS‐Pd/C) are directly synthesized by a solid‐state thermal shock (TS) strategy. Molecular dynamics simulation indicates that the transient super cooling procedure after the TS synthesis can boost the formation of TBs. Benefitting from the abundant TBs and ASs, these metastable Pd NPs can serve as an advanced electrocatalyst for the ethanol oxidation reaction (EOR) with superior reactivity, stability, and CO tolerance in alkaline solutions, which far exceeds that of commercial Pd/C. The first‐principles calculations suggest that the defect structure dominated by TBs can achieve the spatial separation of the optimal adsorption sites for CO and OH. The CO can concentrate at optimal surface sites to minimize the number of poisoned active sites. The strong adsorption of OH can accelerate the EOR process and jointly promote the improvement of electrocatalytic reactivity. [ABSTRACT FROM AUTHOR]

Owing to its unique atomic arrangement and electronic structure, metallic glass (MG) has been widely investigated in the field of energy storage and conversion. In the past few decades, multiple strategies have been developed to synthesize bulk and nanosized MG based materials. Here, combining the structure–activity relationship of MG with electrochemical reaction kinetics, the substantial progress of glass structures in electrocatalytic processes are highlighted, including the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, methanol oxidation reaction, carbon dioxide reduction reaction, and nitrogen fixation. Meanwhile, applications of MG materials in energy storage devices, like supercapacitors and lithium‐ion batteries, are also introduced in detail. Finally, challenges and possibilities for reasonable design of highly‐efficient MG‐based electrode materials are proposed. The integration of high‐throughput methods, artificial intelligence technology, as well as advanced characterization techniques is fundamental to screen materials with remarkable performance. This review aims to deepen the understanding of the relationship between electronic structure and electrochemical performance, providing guidance for rational design of functional MG materials with outstanding activity, selectivity, and durability. [ABSTRACT FROM AUTHOR]

The development of new catalysts is an urgent task in chemistry research because of the increasing demands for higher productivity and efficiency in modern industrial chemistry. High‐throughput (HT) technologies have emerged as powerful accelerators for the discovery of new catalytic materials. Generally, HT techniques involve HT computational screening of catalytic materials and HT experimental approaches. Significant progress has been made in discovering and optimizing catalysts, which demonstrates the speed and economic advantages of HT methods in a matter of process within days and even hours, in contrast with traditional time‐consuming trial and error experiments. From this perspective, the key processes of HT technologies for building a catalysts library are highlighted, including the virtual lab construction based on informatics tools and experimental data lab involving the following processes: 1) design of experiments; 2) reactants prepared manually or automatically; 3) constructing reactor that can well control the variations including materials diversity and reaction conditions (e.g., temperature and reaction time); 4) parallel characterization of fabricated catalysts. Moreover, the correlation between virtual lab and experimental data is discussed to inspire explorations in this field. Furthermore, several remaining challenges of HT technologies accompanied by possible research directions are presented to promote efforts in catalysts library creation. [ABSTRACT FROM AUTHOR]

Rational design of bifunctional efficient electrocatalysts for both oxygen reduction (ORR) and oxygen evolution reactions (OER) is desirable—while highly challenging—for development of rechargeable metal–air batteries. Herein, an efficient bifunctional electrocatalyst is designed and fabricated by encapsulating Co nanoparticles in interconnected N‐doped hollow porous carbon nanofibers (designated as Co@N‐C/PCNF) using an ultrafast high‐temperature shock technology. Benefiting from the synergistic effect and intrinsic activity of the CoNC moiety, as well as porous structure of carbon nanofibers, the Co@N‐C/PCNF composite shows high bifunctional electrocatalytic activities for both OER (289 mV at 10 mA cm−2) and ORR (half‐wave potential of 0.85 V). The CoNC moiety in the composite can modulate the local environmental and electrical structure of the catalysts, thus optimizing the adsorption/desorption kinetics and decreasing the reaction barriers for promoting the reversible oxygen electrocatalysis. Co@N‐C/PCNF‐based aqueous Zn–air batteries (AZAB) provide high power density of 292 mW cm−2, and the assembled flexible ZAB can power wearable devices. [ABSTRACT FROM AUTHOR]

With the low redox potential of −3.04 V (vs SHE) and ultrahigh theoretical capacity of 3862 mAh g−1, lithium metal has been considered as promising anode material. However, lithium metal battery has ever suffered a trough in the past few decades due to its safety issues. Over the years, the limited energy density of the lithium‐ion battery cannot meet the growing demands of the advanced energy storage devices. Therefore, lithium metal anodes receive renewed attention, which have the potential to achieve high‐energy batteries. In this review, the history of the lithium anode is reviewed first. Then the failure mechanism of the lithium anode is analyzed, including dendrite, dead lithium, corrosion, and volume expansion of the lithium anode. Further, the strategies to alleviate the lithium anode issues in recent years are discussed emphatically. Eventually, remaining challenges of these strategies and possible research directions of lithium‐anode modification are presented to inspire innovation of lithium anode. [ABSTRACT FROM AUTHOR]

Tuning the electronic states near the Fermi level can effectively facilitate the reaction kinetics. However, elucidating the role of a specific electronic state of metal oxide in simultaneously regulating the CO2 electroreduction reaction (CO2RR) and competing hydrogen evolution reaction (HER) is still rare, making it difficult to accurately predict the practical CO2RR performance. Herein, replacing the Zn site by heteroatoms with different outer electrons (Mo and Cu) is found to tune both occupied and unoccupied orbitals near the Fermi level of ZnO. Moreover, the different electronic states significantly modulate both CO2RR and HER activity with a totally inverse trend, thus dramatically tuning the practical CO2RR performance. In parallel, the correlation between electronic states, reaction free energies and practical activity is demonstrated. This work provides a possibility for engineering efficient CO2RR eletrocatalysts through tunable composition and electronic structures. [ABSTRACT FROM AUTHOR]

Rechargeable Zn‐ion batteries (RZIBs) are considered to be promising energy storage systems for large‐scale applications owing to their relatively high energy densities and inherently low costs, environmental benignity, as well as safety. With increasing interest and effort being devoted to this field, RZIBs are being tremendously advanced and are very likely to be commercialized in the near future. However, some challenges remain that need to be addressed. Moreover, reported results are quite often overstated through artificial exaggeration and cannot be translated to industrial applications as they were obtained under ideal testing conditions. Therefore, in this perspective, we discuss key parameters that need to be carefully considered when translating laboratory‐developed RZIBs into commercial reality. We also present a critical mini‐review on RZIBs and devote effort to issues that are overlooked in academic research. We believe that this perspective provides new or seldom‐discussed insight for future work and bridges the gap between academia and industry. [ABSTRACT FROM AUTHOR]

Construction of active and durable non‐noble‐metals based electrocatalysts is one of important requirements for the practical application and development of fuel cells, which are presently inhibited by relative sluggish charge transport and reaction kinetics. Herein, highly dispersed ultrathin carbon‐coated nickel oxide nanoparticles settled on carbon cloth (NiO@C/CC) as efficient catalysts for alkaline fuels oxidation are synthesized via an air‐assisted transient thermal shock strategy. This NiO@C/CC catalyst induces an outstanding catalytic activity (up to 119.1 mA cm−2) and durability (a little current decay during tests) in electrooxidation for ethanol, even for methanol and ethylene glycol, which outperforms most of the reported non‐noble metal catalysts. The excellent catalytic performance of NiO@C/CC is essentially attributed to the oxygen vacancies, high concentration, high‐valence‐state Ni, and carbon layers of NiO@C NPs, which contribute to regulate the surface properties and electronic structure, enhance charge transfer, and provide abundant active sites, promoting adsorption capacity of reactant molecules on its surface. The facile and promising air‐assisted transient thermal shock strategy can be extended to guide rational design and rapid synthesis of transition metal compounds as advanced catalysts for alkaline direct alcohol fuel cells. [ABSTRACT FROM AUTHOR]

Personal electronic devices are moving toward an era in pursuit of wearability and versatility enabling a wide range of healthcare, entertainment and sports applications. Conventional power source with bulky and rigid structure becomes a bottleneck for the rapid advancements of wearable smart electronics. To meet the requirement of next‐generation wearable electronics, power supplies with high flexibility, bendability, and stretchability have received extensive attention. In this review, requirements of flexible and wearable power sources in terms of the flexible battery configuration design, flexible materials, energy density and other request are highlighted. Several promising power supplies (e. g., metal−sulfur batteries, metal−air batteries, energy storage and conversion integrated devices) for the application of wearables are discussed in detail. Furthermore, discussions are presented on the remaining challenges and some possible research directions to establish a perspective for practical applications of power sources for wearable electronics in the near future. [ABSTRACT FROM AUTHOR]

Cu2O is a typical photoelectrocatalyst for sustainable hydrogen production, while the fast charge recombination hinders its further development. Herein, Ni2+ cations have been doped into a Cu2O lattice (named as Ni‐Cu2O) by a simple hydrothermal method and act as electron traps. Theoretical results predict that the Ni dopants produce an acceptor impurity level and lower the energy barrier of hydrogen evolution. Photoelectrochemical (PEC) measurements demonstrate that Ni‐Cu2O exhibits a photocurrent density of 0.83 mA cm−2, which is 1.34 times higher than that of Cu2O. And the photostability has been enhanced by 7.81 times. Moreover, characterizations confirm the enhanced light‐harvesting, facilitated charge separation and transfer, prolonged charge lifetime, and increased carrier concentration of Ni‐Cu2O. This work provides deep insight into how acceptor‐doping modifies the electronic structure and optimizes the PEC process. [ABSTRACT FROM AUTHOR]

Rechargeable zinc‐air batteries (ZABs) have attracted much attention as the next‐generation energy conversion and storage devices due to the abundance and environmental friendliness of zinc (Zn) for anode materials, as well as the safety and low cost of aqueous electrolytes. However, rational design of nonprecious and low‐cost integrated air cathode materials with a desirable bifunctional oxygen electrocatalytic performance remains a great challenge for the commercialization of rechargeable ZABs. In previous research studies, various cost‐effective carbon‐supported electrocatalysts and light‐weight carbon‐based current collectors for air cathodes have been developed, showing vast potential in the application of carbon‐based materials. To improve the bifunctional performance and integration of air cathodes, efforts with respect to the design of morphology, defects, and synergistic effects of carbon‐based materials have been made. In this perspective, the general understanding of the air cathode construction and the battery working mechanism is discussed. The recent progress in the design of carbon‐based materials for air cathodes in rechargeable ZABs is summarized. Several possible future research directions and the expected development trends are also discussed, aiming to facilitate the commercialization of advanced rechargeable ZABs in our life. [ABSTRACT FROM AUTHOR]

Functional nanomaterials are playing a crucial role in the emerging field of energy‐related devices. Recently, as a novel synthesis method, high‐temperature shock (HTS), which is rapid, low cost, eco‐friendly, universal, scalable, and controllable, has provided a promising option for the rational design and synthesis of various high‐quality nanomaterials. In this report, the HTS technique, including the equipment setup and operating principle, is systematically introduced, and recent progress in the synthesis of nanomaterials for energy storage and conversion applications using this HTS method is summarized. The growth mechanisms of nanoparticles and carbonaceous nanomaterials are thoroughly discussed, followed by the summary of the characteristic advantages of the HTS strategy. A series of nanomaterials prepared by the HTS method, including carbon‐based films, metal nanoparticles and compound nanoparticles, show high performance in the diverse applications of storage energy batteries, highly active catalysts, and smart energy devices. Finally, the future perspectives and directions of HTS in nanomanufacturing for broader applications are presented. [ABSTRACT FROM AUTHOR]

Highly efficient electrocatalysts play an integral part in developing renewable energy conversion and storage technologies. Despite considerable efforts devoted to synthesizing electrocatalysts with superior performance, the identification of active moieties and understanding of reaction mechanisms under practical conditions still remain elusive. Herein, the substantial progresses in unraveling the local electronic and atomic structure optimizations of nanocatalysts for gas‐involved electrocatalysis, disclosing real active sites, and clarifying their relationships with intrinsic activities by combining advanced characterization techniques with computational simulations are summarized. The continuous development of in situ and ex situ characterization tools, particularly at multi‐scale resolution, to monitor or even directly observe the active center structure is systematically discussed, which is divided into four main categories based on the type of active sites: atomically dispersed active sites, vacancies, heteroatom doping sites, and edge sites. Current challenges and perspectives in both fundamental area and industrial application are finally proposed for the future research direction of next‐generation electrode materials. The aim of this review is to provide mechanistic insights into the real catalytically active structure with the assistance of newly developed characterization techniques, guiding the rational design and structure engineering of advanced functional materials with outstanding activity, selectivity, and durability. [ABSTRACT FROM AUTHOR]

The development of flexible zinc–air battery (ZAB) is highly desirable in achieving superior and stable electrochemical/mechanical properties. Herein, we developed a Zn‐coated foam anode with three‐dimensional (3D) architecture, obtained by electroplating Zn on Cu foam substrate. The compact outer surface and sufficient amount of metallic Zn could be controlled accurately by selecting appropriate porous substrate and electroplating time on Cu foam. Moreover, adding tetraethylammonium hydroxide (TEAOH) to conventional polyvinyl alcohol (PVA)–KOH hydrogel electrolyte effectively improved the water retention of the semi‐solid electrolyte with stable ionic conductivity. The electrolyte precursor fluid was poured on the uneven outer surface of Zn‐coated foam anode and then frozen crosslinked to increase contact between the 3D anode and the electrolyte. A flexible semi‐solid‐state ZAB based on the 3D Zn‐coated foam anode and the hydrogel electrolyte was assembled and exhibited good discharge performance, high energy density (586.5 Wh kgZn−1) and long cycling life. Benefiting from the flexibility of all components, the resultant ZAB performed stable charge and discharge under bending conditions, indicating its promising potential application for flexible and portable energy storage devices. [ABSTRACT FROM AUTHOR]

Simple and stable synthesis of transition metal sulfides and clarification of their growth mechanisms are of great importance for developing catalysts, metal‐air batteries and other technologies. In this work, we developed a one‐step facile hydrothermal approach to successfully synthesize NiS2 microspheres. By changing the experimental parameters, the reason that affects the formation of nanostructured spheres is investigated and discussed in detail, and the formation mechanism of microspheres is proposed innovatively. Furthermore, electrochemical testing results show that the 7 h‐NiS2 catalyst exhibits a remarkable oxygen evolution reaction (OER) activity with an overpotential of 311 mV at 10 mA cm−2 in 1.0 M KOH, superior to precious metal RuO2. The NiS2 catalyst also exhibits a robust durability. This work will contributes to the rational design and the understanding of growth mechanism of transition metal chalcogenide electrocatalysts for diverse energy conversion technologies. [ABSTRACT FROM AUTHOR]

The fabrication of metal‐supported hybrid structures with enhanced properties typically requires external energy input, such as pyrolysis, photolysis, and electrodeposition. In this study, silver‐nanoparticle‐decorated transition‐metal hydroxide (TMH) composites were synthesized by an approach based on a spontaneous redox reaction (SRR) at room temperature. The SRR between silver ions and TMH provides a simple and facile route to establish effective and stable heterostructures that can enhance the oxygen evolution reaction (OER) activity. Ag@Co(OH)x grown on carbon cloth exhibits outstanding OER activity and durability, even superior to IrO2 and many previously reported OER electrocatalysts. Experimental and theoretical analysis demonstrates that the strong electronic interaction between Ag and Co(OH)2 activates the silver clusters as catalytically OER active sites, effectively optimizing the binding energies with reacted intermediates and facilitating the OER kinetics. [ABSTRACT FROM AUTHOR]

Developing superior electrocatalysts for formic acid oxidation (FAO) is the most crucial step in commercializing direct formic acid fuel cells. Herein, we electrodeposited palladium membranes with periodically ordered mesoporosity obtained by asymmetrically replicating the bicontinuous cubic phase structure of a lyotropic liquid‐crystal template. The Pd membrane with the largest periodicity and highest degree of order delivered up to 90.5 m2 g−1 of electrochemical active surface area and 3.34 A mg−1 electrocatalysis capability towards FAO, 3.8 and 7.8 times the values of the commercial Pd/C catalyst, respectively. By controlling the temperature and potential of the electrodeposition procedure, the periodicity area and order degree of the mesoporosity are highly tunable. These Pd membranes gave prototype formic acid fueled cells with 4.3 and 2.4 times the maximum current and power density of the commercial Pd/C catalyst. [ABSTRACT FROM AUTHOR]

The size effect of transition‐metal nanoparticles on electrocatalytic performance remains ambiguous especially when decreasing the size to the atomic level. Herein, we report the spatial isolation of cobalt species on the atomic scale, which was achieved by tuning the zinc dopant content in predesigned bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo‐ZIFs), and led to the synthesis of nanoparticles, atomic clusters, and single atoms of Co catalysts on N‐doped porous carbon. This synthetic strategy allowed an investigation of the size effect on electrochemical behavior from nanometer to Ångström dimensions. Single‐atom Co catalysts showed superior bifunctional ORR/OER activity, durability, and reversibility in Zn–air batteries compared with the other derivatives and noble‐metal Pt/C+RuO2, which was attributed to the high reactivity and stability of isolated single Co atoms. Our findings open up a new avenue to regulate the metal particle size and catalytic performance of MOF derivatives. The spatial isolation of cobalt species on the atomic scale was achieved by tuning the zinc dopant content in predesigned bimetallic Zn/Co zeolitic imidazole frameworks (ZnCo‐ZIFs), and enabled the generation of nanoparticles, atomic clusters, and single atoms of cobalt on N‐doped porous carbon. The single‐atom Co catalysts showed superior bifunctional ORR/OER activity, durability, and reversibility in Zn–air batteries. [ABSTRACT FROM AUTHOR]

Abstract: A mesoporous graphitic carbon‐encapsulated Fe2O3 nanocomposite is synthesized as a superior anode material for sodium‐ion batteries. A threefold strategy is adopted to achieve a high rate performance. First, the mesoporous structure with high specific surface area and large pore volume facilitates the transfer of electrolyte and accommodates the large volume change. Secondly, graphitic carbon encapsulation further improves the electronic conductivity of the nanocomposite. Finally, ultrafine Fe2O3 nanocrystals effectively shorten the Na+ diffusion length. Consequently, this nanocomposite exhibits stable and fast Na+ storage, thus leading to excellent rate capability and cyclability. Pseudocapacitive behavior is found to dominate in the redox reactions, accounting for the outstanding rate and cycling performance. In addition, full cells, assembled with O3‐Na0.9[Cu0.22Fe0.30Mn0.48]O2 as cathodes, present good electrochemical performance. [ABSTRACT FROM AUTHOR]

Abstract: As an emerging battery technology, metal–air flow batteries inherit the advantageous features of the unique structural design of conventional redox flow batteries and the high energy density of metal–air batteries, thus showing great potential as efficient electrochemical systems for large‐scale electrical energy storage. This review summarizes the operating principles and recent progress of metal–air flow batteries from a materials and chemistry perspective, with particular emphasis on the latest advanced materials design and cell configuration engineering, which the authors divide into three categories based on the anode species: vanadium–air, zinc–air, and lithium–air flow batteries. Since some of the capabilities developed for metal–air static batteries can be leveraged for next‐generation flow systems, classical works on conventional metal–air batteries are selected and compared with the metal–air flow systems, highlighting the prominent advantages of the latter in achieving high energy capacity and long cycle performance. At the end, a general perspective on current challenges/opportunities and future research directions to promote the commercial application of the metal–air flow battery technology is provided. The aim is to provide a comprehensive overview and to set up a road map for guiding development from conventional static to advanced flow technologies of metal–air batteries. [ABSTRACT FROM AUTHOR]

Abstract: To improve the utilization efficiency of precious metals, metal‐supported materials provide a direction for fabricating highly active and stable heterogeneous catalysts. Herein, carbon cloth (CC)‐supported Earth‐abundant CoS2 nanosheet arrays (CoS2/CC) are presented as ideal substrates for ultrafine Pt deposition (Pt‐CoS2/CC) to achieve remarkable performance toward the hydrogen and oxygen evolution reactions (HER/OER) in alkaline solutions. Notably, the Pt‐CoS2/CC hybrid delivers an overpotential of 24 mV at 10 mA cm−2 and a mass activity of 3.89 A Ptmg−1, which is 4.7 times higher than that of commercial Pt/C, at an overpotential of 130 mV for catalyzing the HER. An alkali‐electrolyzer using Pt‐CoS2/CC as a bifunctional electrode enables a water‐splitting current density of 10 mA cm−2 at a low voltage of 1.55 V and can sustain for more than 20 h, which is superior to that of the state‐of‐the‐art Pt/C+RuO2 catalyst. Further experimental and theoretical simulation studies demonstrate that strong electronic interaction between Pt and CoS2 synergistically optimize hydrogen adsorption/desorption behaviors and facilitate the in situ generation of OER active species, enhancing the overall water‐splitting performance. This work highlights the regulation of interfacial and electronic synergy in pursuit of highly efficient and durable supported catalysts for hydrogen and oxygen electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Abstract: SnS2/graphene composites have attracted extensive attention in energy storage owing to their excellent electrochemical performance. However, most of the previous methods to synthesize SnS2/graphene composites require long times, high temperatures, or high pressures, which are obstacles for practical low‐cost production. A simple one‐pot strategy to prepare SnS2/graphene composites has been developed, which is not time‐consuming (1 h) and requires moderate temperature (75 °C) in atmosphere. Through this method, ultrafine SnS2 nanoparticles anchored on graphene nanosheets are prepared and exhibit excellent electrochemical performance for both lithium and sodium storage. Specifically, as anodes for lithium‐ion batteries, the SnS2/graphene electrode delivers a high capacity of 1480 mAh g−1 after 50 cycles at 0.2 A g−1. Even at 10 A g−1, the SnS2/graphene electrode can achieve a capacity of 666 mAh g−1. A constructed full lithium‐ion cell exhibits a capacity of 957 mAh g−1 after 50 cycles at 1 A g−1. This simple one‐pot strategy may pave the way for large‐scale production and practical application of SnS2/graphene composites in energy storage. [ABSTRACT FROM AUTHOR]

Abstract: Tuning the catalytic active sites plays a crucial role in developing low cost and highly durable oxygen electrode catalysts with precious metal‐competitive activity. In an attempt to engineer the active sites in Co3O4 spinel for oxygen electrocatalysis in alkaline electrolyte, herein, controllable synthesis of surface‐tailored Co3O4 nanocrystals including nanocube (NC), nanotruncated octahedron (NTO), and nanopolyhedron (NP) anchored on nitrogen‐doped reduced graphene oxide (N‐rGO), through a facile and template‐free hydrothermal strategy, is provided. The as‐synthesized Co3O4 NC, NTO, and NP nanostructures are predominantly enclosed by {001}, {001} + {111}, and {112} crystal planes, which expose different surface atomic configurations of Co2+ and Co3+ active sites. Electrochemical results indicate that the unusual {112} plane enclosed Co3O4 NP on rGO with abundant Co3+ sites exhibit superior bifunctional activity for oxygen reduction and evolution reactions, as well as enhanced metal–air battery performance in comparison with other counterparts. Experimental and theoretical simulation studies demonstrate that the surface atomic arrangement of Co2+/Co3+ active sites, especially the existence of octahedrally coordinated Co3+ sites, optimizes the adsorption, activation, and desorption features of oxygen species. This work paves the way to obtain highly active, durable, and cost‐effective electrocatalysts for practical clean energy devices through regulating the surface atomic configuration and catalytic active sites. [ABSTRACT FROM AUTHOR]

A facile and binder-free method is developed for the in situ and horizontal growth of ultrathin mesoporous Co3O4 layers on the surface of carbon fibers in the carbon cloth (ultrathin Co3O4/CC) as high-performance air electrode for the flexible Zn-air battery. In particular, the ultrathin Co3O4 layers have a maximum contact area on the conductive support, facilitating the rapid electron transport and preventing the aggregation of ultrathin layers. The ultrathin feature of Co3O4 layers is characterized by the transmission electron microscopy, Raman spectra, and X-ray absorption fine structure spectroscopy. Benefiting from the high utilization degree of active materials and rapid charge transport, the mass activity for oxygen reduction and evolution reactions of the ultrathin Co3O4/CC electrode is more than 10 times higher than that of the carbon cloth loaded with commercial Co3O4 nanoparticles. Compared to the commercial Co3O4/CC electrode, the flexible Zn-air battery using ultrathin Co3O4/CC electrode exhibits excellent rechargeable performance and high mechanical stability. Furthermore, the flexible Zn-air battery is integrated with a flexible display unit. The whole integrated device can operate without obvious performance degradation under serious deformation and even during the cutting process, which makes it highly promising for wearable and roll-up optoelectronics. [ABSTRACT FROM AUTHOR]

The electrochemical stability of the Pt(100) surface is investigated by electrochemical methods and morphological and structural characterization. Preferentially (100)-oriented Pt is prepared by three different methods: use of water-in-oil microemulsions, electrodeposition and electrochemical faceting. The loss of the Pt(100) sites particularly the wide (100) surface domains during the potential cycling is confirmed by the hydrogen-desorption profile in H2SO4 solution, the decreasing specific activity for ammonia electro-oxidation and the decreasing proportion of Pt(100) sites as characterized by irreversible Ge adsorption. This is consistent with TEM observations that show that the well-defined cubic Pt nanocubes change to a polycrystalline structure, whereas the sharp tips of electrodeposited Pt nanoparticles become rounded/blunt or disappear after 300 potential cycles. Noticeably, the bulk Pt disk electrode treated by electrochemical faceting exhibits a much higher electrochemical stability compared to preferentially (100)-oriented Pt nanoparticles. The high electrochemical stability is probably related to its preparation procedure, which involves high-frequency selective electrodissolution/electrodeposition of Pt atoms coupled to the periodic adsorption/desorption of oxygen-containing species and hydrogen adatoms. [ABSTRACT FROM AUTHOR]

Pt-monolayer-decorated Au particles with different surface morphologies were prepared by Au electrodeposition, followed by Cu under-potential deposition and a Pt replacement reaction. Spherical Au particles with relatively smooth surfaces and flower-like Au particles consisting of interconnecting thin nanosheets were obtained by controlling the deposition potential and electrolyte concentration. Pt-monolayer-decorated flower-like Au particles exhibit much higher specific activity and stability in the electrooxidation of methanol, ethanol and ammonia compared to Pt-monolayer-decorated spherical Au particles. Pt-monolayer-decorated flower-like Au particles also showed better poisoning-tolerance, especially in the electrooxidation of methanol. The improved electrocatalytic performance is attributed to the high density of catalytically active sites such as surface atomic steps, the edges at sharp tips and edges on the surface of the flower-like particles, which is revealed by spherical-aberration-corrected transmission electron microscopy with atomic resolution. [ABSTRACT FROM AUTHOR]

Alcohol Oxidation: Air-Assisted Transient Synthesis of Metastable Nickel Oxide Boosting Alkaline Fuel Oxidation Reaction (Adv. Keywords: alcohols oxidation reactions; metastable; nickel oxide; oxygen vacancies; transient thermal shock EN alcohols oxidation reactions metastable nickel oxide oxygen vacancies transient thermal shock 1 1 1 12/10/20 20201208 NES 201208 In article number 2001397, Yanan Chen, Yida Deng, and co-workers report the fabrication of metastable NiO nanoparticles on carbon cloth (NiO@C/CC) via an air-assisted thermal shock technique (ATS-tech) as an efficient alcohol oxidation reaction catalyst. Alcohols oxidation reactions, metastable, nickel oxide, oxygen vacancies, transient thermal shock. [Extracted from the article]

Developing low‐cost, high‐capacity, high‐rate, and robust earth‐abundant electrode materials for energy storage is critical for the practical and scalable application of advanced battery technologies. Herein, the first example of synthesizing 1D peapod‐like bimetallic Fe2VO4 nanorods confined in N‐doped carbon porous nanowires with internal void space (Fe2VO4⊂NC nanopeapods) as a high‐capacity and stable anode material for potassium‐ion batteries (KIBs) is reported. The peapod‐like Fe2VO4⊂NC nanopeapod heterostructures with interior void space and external carbon shell efficiently prevent the aggregation of the active materials, facilitate fast transportation of electrons and ions, and accommodate volume variation during the cycling process, which substantially boosts the rate and cycling performance of Fe2VO4. The Fe2VO4⊂NC electrode exhibits high reversible specific depotassiation capacity of 380 mAh g−1 at 100 mA g−1 after 60 cycles and remarkable rate capability as well as long cycling stability with a high capacity of 196 mAh g−1 at 4 A g−1 after 2300 cycles. The first‐principles calculations reveal that Fe2VO4⊂NC nanopeapods have high ionic/electronic conductivity characteristics and low diffusion barriers for K+‐intercalation. This study opens up new way for investigating high‐capacity metal oxide as high‐rate and robust electrode materials for KIBs. [ABSTRACT FROM AUTHOR]