The electrochemical production of sustainable hydrogen under neutral conditions is advantageous, as it allows for the use of wastewater or seawater without the need for pH adjustments. However, the low ion concentration in neutral electrolytes typically results in limited adsorption of reactants on the catalyst surfaces, leading to sluggish reaction kinetics. Therefore, enhancing absorption capacity is a key challenge in the development of neutral hydrogen evolution reaction (HER) catalysts. Hetero‐structured catalysts may improve surface adsorption through extensive interfacing between phases, enabling active transportation of reaction intermediates. Integrating metal sulfides and oxides, in particular, holds the potential for generating efficient electrocatalysts with improved HER activity and surface adsorption capacity. Herein, the synthesis of CrOx‐doped Co9S8/CuCrS2 mosaic hetero‐nanostructures is reported as a proficient HER catalyst. Facile Cr‐cation migration at the Co9S8/CuCrS2 interface enables the preparation of Cr‐oxide sub‐nano domains within the sulfide matrix, boosting the HER catalysis in neutral media. The exceptional electrochemical performance is demonstrated in a pH 7.4 phosphate buffer solution, including low overpotential, small Tafel slope, and stability over 60 h. The formulation of catalyst design and synthetic approaches has the potential to pave the way for diverse catalytic applications utilizing metal oxide‐doped hetero‐nanostructures.

中文翻译：

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利用亲氧 CrOx 马赛克掺杂剂促进中性介质中 Co9S8 的析氢反应


在中性条件下电化学生产可持续氢气是有利的，因为它允许使用废水或海水而无需调整 pH 值。然而，中性电解质中的低离子浓度通常会导致催化剂表面反应物的吸附有限，从而导致反应动力学缓慢。因此，提高吸收能力是中性析氢反应 （HER） 催化剂开发中的关键挑战。异质结构催化剂可以通过相之间的广泛界面来改善表面吸附，从而实现反应中间体的主动运输。特别是整合金属硫化物和氧化物，有可能产生具有更高 HER 活性和表面吸附能力的高效电催化剂。在此，CrOx 掺杂的 Co9S8/CuCrS2 马赛克异纳米结构的合成被报道为一种熟练的 HER 催化剂。Co9S8/CuCrS2 界面处的简单 Cr-cation 迁移能够在硫化物基质中制备 Cr-oxide 亚纳米结构域，从而促进中性介质中的 HER 催化。在 pH 值为 7.4 的磷酸盐缓冲溶液中证明了卓越的电化学性能，包括低过电位、小塔菲尔斜率和 60 小时以上的稳定性。催化剂设计和合成方法的制定有可能为利用金属氧化物掺杂异纳米结构的多样化催化应用铺平道路。