materials, [2] and their coupled composites. [3] Among them, TM singleatom catalysts (SACs) have recently emerged as a new type of frontier materials with high activity, stability, and selectivity, rendering the great potential for diverse catalytic systems. [4] The unique electronic structure, maximized atomutilization efficiency, and unsaturated coordination bonds of the active centers in SACs contribute to the enhanced performance. [5] Moreover, recent investigations have demonstrated that the introduction of secondary metal atoms can further enhance the activity of SACs, indicating the promising development of dual-metal SACs. [6] Nevertheless, on the one hand, there is a serious lack of effective strategies to achieve the atomic control of targeted reactive sites comprising binary metal atoms; on the other hand, the identification of the diatomic structure in dual-metal SACs and the deeper functional mechanism of bimetallic atoms for synergistic catalysis are still in their infancy.Owing to the increasing concerns from energy and environmental issues, growing attention has been paid on developing sustainable energy conversion and storage technologies, such as water-splitting electrolyzers, fuel cells, metal-air batteries, etc. [7] However, the sluggish kinetics of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) on the electrodes has been proven to With the inspiration of developing bifunctional electrode materials for reversible oxygen electrocatalysis, one strategy of heteroatom doping is proposed to fabricate dual metal single-atom catalysts. However, the identification and mechanism functions of polynary single-atom structures remain elusive. Atomically dispersed binary Co-Ni sites embedded in N-doped hollow carbon nanocubes (denoted as CoNi-SAs/NC) are synthesized via proposed pyrolysis of dopamine-coated metalorganic frameworks. The atomically isolated bimetallic configuration in CoNi-SAs/NC is identified by combining microscopic and spectroscopic techniques. When employing as oxygen electrocatalysts in alkaline medium, the resultant CoNi-SAs/NC hybrid manifests outstanding catalytic performance for bifunctional oxygen reduction/evolution reactions, boosting the realistic rechargeable zinc-air batteries with high efficiency, low overpotential, and robust reversibility, superior to other counterparts and state-of-the-art precious-metal catalysts. Theoretical computations based on density functional theory demonstrate that the homogenously dispersed single atoms and the synergistic effect of neighboring Co-Ni dual metal center can optimize the adsorption/desorption features and decrease the overall reaction barriers, eventually promoting the reversible oxygen electrocatalysis. This work not only sheds light on the controlled synthesis of atomically isolated advanced materials, but also provides deeper understanding on the structure-performance relationships of nanocatalysts with multiple active sites for various catalytic applications.To date, large numbers of low cost and efficie...

Hierarchical NiMoO4 architectures assembled from well‐aligned uniform nanosheets or nanorods are successfully grown on various conductive substrates using a facile and effective general approach. Importantly, the nanostructures of NiMoO4 can be easily controlled to be nanosheets or nanorods by using different solvents. By virtue of their intriguing structure features, NiMoO4 nanosheets as integrated additive‐free electrodes for supercapacitors manifest higher Faradaic capacitance than NiMoO4 nanorods. Moreover, an asymmetric supercapacitor (ASC) is constructed using the as‐prepared NiMoO4 nanosheets as the positive electrode and activated carbon (AC) as the negative electrode. The optimized ASC with an extended operating voltage range of 0–1.7 V displays excellent electrochemical performance with a high energy density of 60.9 Wh kg−1 at a power density of 850 W kg−1 in addition to superior rate capability. Furthermore, the NiMoO4//AC ASC device exhibits remarkable cycling stability with 85.7% specific capacitance retention after 10 000 cycles. The results show that these NiMoO4‐based nanostructures are promising for high‐energy supercapacitors.

We report the synthesis of ultrathin S-doped MoSe 2 nanosheets demonstrating enhanced HER catalysis with a low onset overpotential of 90 mV and a Tafel slope of 58 mV per decade. We attribute the improved catalytic effects to the proliferation of unsaturated HER active sites in MoSe 2 resulting from S-doping.

Metal single‐atom materials with their high atom utilization efficiency and unique electronic structures usually show remarkable catalytic performances in many crucial chemical reactions. Herein, a facile and easily scalable “impregnation‐carbonization‐acidification” strategy for fabricating a class of single‐atom‐anchored (including cobalt and nickel single atoms) monolith as superior binder‐free electrocatalysts for developing high‐performance wearable Zn–air batteries is reported. The as‐prepared single atoms, supported by N‐doped carbon flake arrays grown on carbon nanofibers assembly (M SA@NCF/CNF), demonstrate the dual characteristics of excellent catalytic activity (reversible oxygen overpotential of 0.75 V) and high stability, owing to the greatly improved active sites' accessibility and optimized single‐sites/pore‐structures correlations. Furthermore, wearable Zn–air battery based on Co SA@NCF/CNF air electrode displays superior stability under deformation, satisfactory energy storage capacity, and good practicality to be utilized as an integrated battery system. Theoretical calculations reveal a mechanism for the promotion of the catalytic performances on single atomic sites by lowering the overall oxygen reduction/evolution reaction barriers comparing to metal cluster co‐existing configuration. These findings provide a facile strategy for constructing free‐standing single‐atom materials as well as the engineering of high‐performance binder‐free catalytic electrodes.

Exploitation of high-performance anode materials is essential but challenging to the development of sodium-ion batteries (SIBs). Among all proposed anode materials for SIBs, sulfides have been proved promising candidates due to their unique chemical and physical properties. In this work, a facile solvothermal method to in situ decorate cobalt sulfide (CoS) nanoplates on reduced graphene oxide (rGO) to build CoS@rGO composite is described. When evaluated as anode for SIBs, an impressive high specific capacity (540 mAh g(-1) at 1 A g(-1) ), excellent rate capability (636 mAh g(-1) at 0.1 A g(-1) and 306 mAh g(-1) at 10 A g(-1)), and extraordinarily cycle stability (420 mAh g(-1) at 1 A g(-1) after 1000 cycles) have been demonstrated by CoS@rGO composite for sodium storage. The synergetic effect between the CoS nanoplates and rGO matrix contributes to the enhanced electrochemical performance of the hybrid composite. The results provide a facile approach to fabricate promising anode materials for high-performance SIBs.