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.

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which is also considered a biorenew able energy carrier. However, the anodic ethanol oxidation reaction (EOR) is a complicated and kinetically sluggish process, involving the transfer of multiple electrons and various reaction intermediates and products. Typically, the C2-pathway dominates the EOR in both acidic and alkaline electrolytes, resulting in the formation of acetic acid or acetate by delivering four electrons, and acetaldehyde by delivering two electrons, respectively. The C1-pathway, which involves complete oxidation and the transfer of 12 electrons generating CO 2 or carbonate, is preferred to the C2-pathway, aiming for maximum DEFCs efficiency. [1][2][3][4][5] Specially, highly efficient catalysts have been developed by engineering Pt-based nanocrystals, and the C1-pathway selectivity has been promoted by Rh-based catalysts. [6][7][8][9] In designing electrochemical surfaces toward maximum performance, modifying the electronic structure and strain of catalytic surfaces are considered state-of-the-art strategies, which can for instance be achieved by introducing metals with different intrinsic reactivities and constructing core-shell nanostructures, respectively. [10][11][12][13][14][15] Combining these approaches in a rational manner would be a promising way to substantially improve the EOR, yet the underlying knowledge about their contributions is largely lacking. [10][11][12][13][14][15][16][17][18] Therefore, it is highly desirable to employ tailored nanostructures to resolve these important issues and contribute to the practical deployment of DEFCs by identifying versatile EOR electrocatalysts possessing high atom utilization of noble metals, high mass-normalized activity at low overpotentials, high C1-pathway selectivity, long-term durability, and superior anti-poisoning ability. [1] To maximize atom utilization, single-atom catalysts (SACs) have emerged as one of the most promising frontiers in materials chemistry. [19][20][21] Using specific support materials such as reducible metal oxides, activated carbons, and anisotropic materials such as MoS 2 , single atoms of catalytically metals can be stabilized, which exhibit intriguing physicochemical properties compared with their counterpart clusters and nanoparticles. [22][23][24] Typically, high-performance EOR catalysts should facilitate multiple dehydrogenation and oxidation steps as well as CC bond cleavage reactions. All these reactions typically require ensembles of surface metal atoms, implying that thisThe rational design and control of electrocatalysts at single-atomic sites could enable unprecedented atomic utilization and catalytic properties, yet it remains challenging in multimetallic alloys. Herein, the first example of isolated Rh atoms on ordered PtBi nanoplates (PtBi-Rh 1 ) by atomic galvanic replacement, and their subsequent transformation into a tensile-strained Pt-Rh single-atom alloy (PtBi@PtRh 1 ) via electrochemical dealloying are presented. Benefiting from the Rh 1 -tailored Pt (110) surface with tensile strain, the PtBi@...

The control of multimetallic ensembles at the atomic‐level is challenging, especially for high‐entropy alloys (HEAs) possessing five or more elements. Herein, the one‐pot synthesis of hexagonal‐close‐packed (hcp) PtRhBiSnSb high‐entropy intermetallic (HEI) nanoplates with intrinsically isolated Pt, Rh, Bi, Sn, and Sb atoms is reported, to boost the electrochemical oxidation of liquid fuels. Taking advantage of these combined five metals, the well‐defined PtRhBiSnSb HEI nanoplates exhibit a remarkable mass activity of 19.529, 15.558, and 7.535 A mg−1Pt+Rh toward the electrooxidation of methanol, ethanol, and glycerol in alkaline electrolytes, respectively, representing a state‐of‐the‐art multifunctional electrocatalyst for alcohol oxidation reactions. In particular, the PtRhBiSnSb HEI achieves record‐high methanol oxidation reaction (MOR) activity in an alkaline environment. Theoretical calculations demonstrate that the introduction of the fifth metal Rh enhances the electron‐transfer efficiency in PtRhBiSnSb HEI nanoplates, which contributes to the improved oxidation capability. Meanwhile, robust electronic structures of the active sites are achieved due to the synergistic protections from Bi, Sn, and Sb sites. This work offers significant research advances in developing well‐defined HEA with delicate control over compositions and properties.

It remains an ongoing challenge to develop cheap, highly active, and stable electrocatalysts to promote the sluggish electrocatalytic oxygen evolution, oxygen reduction, and hydrogen evolution reactions for rechargeable metal-air batteries and water-splitting systems. In this work, we report the morphology-controllable synthesis of zinc cobalt mixed sulfide (Zn-Co-S) nanoarchitectures, including nanosheets, nanoplates, and nanoneedles, grown on conductive carbon fiber paper (CFP) and the micronanostructure dependent electrochemical efficacy for catalyzing hydrogen and oxygen in zinc-air batteries and water electrolysis. The formation of different Zn-Co-S morphologies was attributed to the synergistic effect of decomposed urea products and the corrosion of NHF. Among synthesized Zn-Co-S nanostructures, the nanoneedle arrays supported on CFP exhibit superior trifunctional activity for oxygen reduction, oxygen evolution, and hydrogen evolution reactions than its nanosheet and nanoplate counterparts through half reaction testing. It also exhibited better catalytic durability than Pt/C and RuO. Furthermore, the Zn-Co-S nanoneedle/CFP electrode enables rechargeable Zn-air batteries with low overpotential (0.85 V), high efficiency (58.1%), and long cycling lifetimes (200 cycles) at 10 mA cm as well as considerable performance for water splitting. The superior performance is contributed to the integrated nanoneedle/CFP nanostructure, which not only provides enhanced electrochemical active area, but also facilitates ion and gas transfer between the catalyst surface and electrolyte, thus maintaining an effective solid-liquid-gas interface necessary for electrocatalysis. These results indicate that the Zn-Co-S nanoneedle/CFP system is a low cost, highly active, and durable electrode for highly efficient rechargeable zinc-air batteries and water electrolysis in alkaline solution.