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Single‐crystal Ni‐rich LiNi1−x−yCoxMnyO2 (NCM) cathodes have garnered widespread attention in the lithium‐ion battery community due to their unique advantages in mechanical performance and their ability to minimize interfacial electrochemical side reactions. The synthesis of single‐crystal materials with monodisperse and appropriate size, minimal lattice defects, and highly ordered structures is the key for high‐performance batteries. However, achieving this goal poses challenges due to the lack of in‐depth understanding regarding specific experimental parameters and the solid reaction mechanism during the synthesis process. In this review, the aim is to provide an in‐depth analysis of the critical process parameters involved in the synthesis and their impact on crystal morphology, structure, and electrochemical performance. Consequently, the first section focuses on the effect of the precursor morphology, lithium salt, atmosphere, and sintering procedure. In the second section, the study delves into an in‐depth discussion of the solid reaction and crystal growth mechanism. Lastly, it is concluded by highlighting the prospects and challenges associated with the synthesis and application of single‐crystal Ni‐rich NCM cathodes. [ABSTRACT FROM AUTHOR]

The realization of seawater electrolysis requires the development of electrode materials that can meet the requirements of high activity, high selectivity, and corrosion resistance. Herein, this work successfully prepares a molybdate (MoO42−)‐modulated nickel‐iron oxide electrode for seawater electrolysis via a quick and easy thermal shock method, with high activity and extraordinary durability in oxygen evolution reaction (OER) for seawater electrolysis. The experimental analyses and theoretical calculations reveal that the in situ generated MoO42− on the surface of electrode can modulate and stabilize the catalytic active phase γ‐(Ni, Fe)OOH, improving the OER activity, as well as play a critical role in protecting electrode from chloride ions (Cl−) corrosion for extended service life. This catalyst thus displays an evidently slow degradation rate of 20 µV h−1 during a long‐term operation (>1500 h) at 100 mA cm−2. This work provides a new viewpoint for the design of oxyanion‐modified catalysts and can be widely used to address the challenges in seawater electrolysis. [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]

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]

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.