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Defect engineering is demonstrated to be an important factor in enhancing the electrochemical performance of lithium‐ion batteries by improving structural stability and ion diffusion. However, conventional synthetic methods have long and complicated processes, making it challenging to effectively and easily introduce defects into electrode materials. In this work, a high‐temperature shock technique (HTS) with an ultrafast heating and cooling process that can quickly introduce twin boundaries (TBs) into phase‐pure spinel LiMn2O4 in seconds is reported. Various ex situ techniques reveal the crystallization mechanism of LiMn2O4 during ultrafast synthesis. LiMn2O4 with TBs exhibits a higher rate performance than that obtained from the traditional method. Additionally, alien elements can be evenly incorporated into LiMn2O4 in seconds, resulting in excellent cycling performance. For instance, 2% Ni‐doped LiMn2O4 shows an initial capacity of 121 mAh g−1 and retention of 86.5% after 500 cycles at 1 C. [ABSTRACT FROM AUTHOR]

Atomically precise composite site‐based catalysts with new electrocatalytic synergistic mechanisms and enhanced electrocatalytic activities have emerged as a frontier in the electrocatalysis community. This topical review focuses on the recent research advances of atomically precise metal composite sites‐based electrocatalysts. This work first demonstrates an overview of the configurations of atomically precise composite sites, including a discussion of the advanced methods employed for understanding the composite sites. The review then provides a comprehensive organization of the previously reported methodologies of synthesizing electrocatalysts with atomically precise composite sites. Representative case studies are provided, starting from the simple one‐step pyrolysis strategy to the species‐by‐species multi‐step pyrolysis strategy. Based on the preceding discussions of the catalyst materials, the review further discusses the unique electrocatalysis mechanisms raised by the composite sites, that are different from the routine single species sites. The electrocatalytic systems mainly involve the oxygen reduction reaction, oxygen evolution reaction, hydrogen evolution reaction, nitrogen reduction reaction, and carbon dioxide reduction reaction. The themes of this section include the true active center determination for composite sites and various types of electrocatalytic synergy mechanisms. Finally, critical unanswered questions and remaining challenges, as well as promising underexplored research directions are identified. [ABSTRACT FROM AUTHOR]

MXenes are promising substrates for supported noble metal electrocatalysts. Yet, it is a significant challenge to modulate the metal–support interaction (MSI) for enhancing catalytic performance. Herein, employing a facile HF etching method, the cation vacancy structures in Ti3C2Tx MXenes are controllably tuned, producing nearly vacancy‐free (Ti3C2Tx‐V0), single Ti atom vacancy (Ti3C2Tx‐VS), or Ti vacancy cluster (Ti3C2Tx‐VC) engineered MXenes. Ruthenium atomic clusters, as a model catalyst, successfully anchor on all MXene substrates. Different from the terminal O/F coordination groups on routine Ti3C2Tx MXene surfaces, the Ti vacancy clusters in Ti3C2Tx‐VC create unique lattice carbon ligand environment toward Ru species, which induces ultra‐strong MSI. As a result, compared to Ti3C2Tx‐V0 and Ti3C2Tx‐VS, the Ti3C2Tx‐VC modulated Ru clusters (Ru@Ti3C2Tx‐VC) exhibit the optimized balance of H2O adsorption/dissociation and OH/H desorption, thereby delivering superior electrocatalytic performance in the alkaline hydrogen evolution reaction (HER). Within the wide range from laboratory‐level (90 mA cm−2) to industrial‐level (1.5 A cm−2) current density, Ru@Ti3C2Tx‐VC outperforms commercial Pt/C in terms of overpotential and mass activity. Moreover, as a universal substrate for noble metal catalysts, Ti3C2Tx‐VC can also anchor Ir/Pt/Rh atomic clusters and enable excellent HER catalytic activity. This work expands the scope of the MSI between MXene and noble metal catalysts. [ABSTRACT FROM AUTHOR]

Alloying platinum with early transition metals is a promising approach to optimize the adsorption behaviors of catalysts. Nevertheless, the large negative redox potential between early transition metals and Pt hinders the fabrication of such alloys. Herein, a strategy combining the thermal shock technique with electrochemical activation to prepare Pt3V alloy as a hydrogen evolution reaction catalyst is reported for the first time. Electrochemical tests show that the as‐prepared catalyst exhibits exceptional catalytic activity and durability in 0.5 m H2SO4, surpassing the state‐of‐the‐art 20 wt.% Pt/C. The catalyst can maintain its activity after 100 h tests without evident decay under the current density of 500 mA cm−2. Theoretical calculations demonstrate that the optimized hydrogen absorption and high vacancy formation energy of Pt3V contributes to the enhanced electrocatalytic activity and stability. This work may spur future research for other Pt‐based early transition metal alloy catalysts for electrocatalysis. [ABSTRACT FROM AUTHOR]

Supercapacitor (SC) is one of the most promising electrochemical energy‐storage devices. However, the practical application of SCs is limited by the low‐energy density. Herein, high‐temperature shock (HTS)‐derived ultrafine structure‐activated porous carbon (UAPC) with N, O functional groups is reported as high‐energy density SCs carbon. The process of ultrafast joule heating and cooling effectively transfers general‐purposed carbon into electrochemical‐activated carbon. The UAPC‐based SCs exhibit an energy density of up to 129 Wh kg−1 in EMIMBF4 ionic liquid, which outperform almost all reported and commercial SCs (22 Wh kg−1). The outstanding electrochemical performance of UAPC is attributed to the ultrafine structure and N, O functional groups, which enlarges the surface area, improves the surface wettability of UAPC electrodes, and provides pseudocapacitance. The facile and efficient ultrafast‐processing strategy has opened up an unprecedented pathway for the application of low‐value carbon for the electrode design and application of SCs. [ABSTRACT FROM AUTHOR]

Constructing novel heterostructures is an effective way for enhancing the oxygen electrocatalytic properties of the catalysts. In this work, a class of Janus homologous heterostructures, compositing transition metal alloys with their corresponding sulfides (TM/TMS), are controllably synthesized through an ultrafast high‐temperature shock (HTS) strategy. The ultrafast sintering rate and carbothermal reduction reaction lead to the formation of sulfides and partial reduction of sulfides to alloys, while the ultrafast cooling rate keeps the homologous heterostructure of TM/TMS stable. The components of TMs in the composites can be well controlled from unary to quaternary. Moreover, benefiting from the synergistic effect of the metallic sites in the interfaces, the adsorption and desorption energy barrier of the active intermediates are significantly optimized and thus leading to the enhanced oxygen catalytic performance. Impressively, the aqueous zinc‐air battery (ZAB) using the binary homologous nanocomposite FeCo/(FeCo)S as air cathodes achieves impressive durability (> 470 cycles) and power density (261.8 mW cm−2). The as‐assembled flexible ZAB can well power the wearable devices and can work for at least 300 cycles without obvious degradation. This work opens a new chemical space for designing homologous heterostructures for their application in energy storage and conversion systems. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been identified as pre‐electrocatalysts for the oxygen evolution reaction (OER) and the high valent TMs in the in situ generated oxyhydroxides are considered to be the real OER catalytic center. However, the role of chalcogens for OER process has been ignored and not fully elucidated. Herein, it is discovered that about 2.8–3.5% of chalcogens remain in as oxidized derivatives at a steady state, which plays a vital role for enhancing the catalytic activity. A facile and spontaneous sulfurizing method is developed to synthesize sulfur‐doped NiCo‐(oxy)hydroxysulfides (NCOSH) nanosheets, in which the sulfur can directly bond with high‐valence TMs and keep them stable for OER catalysis. Theoretical and experimental results suggest that the S‐coordination in NCOSH can cause bond length strengthening and electronic modulation between TM‐S and TM‐O, thus enhancing the oxidation activity and stability of high‐valence TMs in NCOSH. Consequently, the as‐obtained NCOSH exhibits superior bifunctional activities and durability for oxygen electrocatalytic reactions, and also serves as a superb air cathode in rechargeable solid state Zn‐air batteries. This work sheds light on the rational design of (oxy)hydroxysulfides as efficient electrocatalysts and gains deeper fundamental insights on the enhancing mechanism of S in oxyhydroxysulfides for diverse electrochemical applications. [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]

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]

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]

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: 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]

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]

Highlights from the article: Keywords: 2D-nanosheets; honeycombed carbon; interfacial interaction; ReS2; sodium-ion batteries In article number 1901146, Naiqin Zhao, Shi-Zhang Qiao and co-workers confine 1T'-ReS SB 2 sb in 2D-honeycombed carbon nanosheets for sodium-ion battery anodes. Interfacial interaction, sodium-ion batteries, ReS2, 2D-nanosheets, honeycombed carbon.

Highlights from the article: Electrocatalysis: Mesoporous Decoration of Freestanding Palladium Nanotube Arrays Boosts the Electrocatalysis Capabilities toward Formic Acid and Formate Oxidation (Adv. Keywords: electrocatalysis; formate oxidation; formic acid oxidation; mesoporosity; Pd nanotube arrays Electrocatalysis, formate oxidation, formic acid oxidation, mesoporosity, Pd nanotube arrays.

Fabricating high‐performance electrocatalysts is the most critical step in commercializing direct formic acid or formate fuel cells. In this work, a dual‐template electrodeposition method is used to create freestanding mesoporosity decorated palladium nanotube arrays (P‐PdNTA) as a bifunctional electrocatalyst toward formic acid and formate oxidation (FAO/FOR). The phytantriol‐based soft template modifies the superficial chemistry of aluminum anodic oxide inner surfaces, thereby facilitating the regulated electrodeposition of highly stable palladium nanotubes. The sacrifice of the soft template generates substantial mesoporosity on the nanotubes, resulting in a 189% increase in the electrochemically active surface area with respect to the mesopore‐free PdNTA baseline. In addition, the soft template significantly increases the density of catalytically active sites per unit area via perturbation on routine nanotube growth, as evidenced by the doubled areal catalytic activity of P‐PdNTA versus PdNTA. Remarkably, the P‐PdNTA delivered gravimetric catalytic currents of 3.65 and 3.87 A mg−1 for FAO and FOR, which are 8.5 and 6.5 times higher, respectively, than those of commercial Pt/C. These values are among the most favorable reported and benefit from the unique synergy of fast substance transport, large electrochemical active surface area and high areal population of catalytically active sites. [ABSTRACT FROM AUTHOR]

Flexible Zn‐based batteries are emerging candidates for wearable electronics owing to the natural merits of zinc, such as environmental friendliness and low cost. In article number 1802605 by Cheng Zhong, Jun Lu, and co‐workers, the challenges of developing flexible Li‐ion batteries are presented. Thereafter, a brief overview of recent progress in the development of flexible Zn‐based rechargeable batteries from the perspective of energy density, rechargeability, flexible electrolytes, and some other issues that remain to be addressed, are highlighted. [ABSTRACT FROM AUTHOR]

Flexible Zn‐based batteries are regarded as promising alternatives to flexible lithium‐ion batteries for wearable electronics owing to the natural advantages of zinc, such as environmental friendliness and low cost. In the past few years, flexible Zn‐based batteries have been studied intensively and exciting achievements have been obtained in this field. However, the development of flexible Zn‐based batteries is still at an early stage. The challenges of developing flexible lithium‐ion batteries are presented here. Then, a brief overview of recent progress in flexible zinc secondary batteries from the perspective of advanced materials and some issues that remain to be addressed are discussed. Flexible rechargeable Zn‐based batteries are promising power sources for wearable electronics. Recent progress in flexible Zn‐based batteries is discussed here and some issues that need to be addressed in the further development of flexible Zn‐based batteries to meet the requirements of wearable electronics are outlined. [ABSTRACT FROM AUTHOR]