Interface engineering is an effective approach towards developing low-cost highly efficient electrocatalysts for green hydrogen production in alkaline water or seawater environments. Herein, we have successfully fabricated an interface engineered Mott-Schottky heterostructure catalyst i.e., Fe₃O₄@Ni₃S₂, in which, Ni₃S₂ nanosheets are evenly dispersed on the surface of Fe₃O₄ flower-like nanosheets, which are supported by a Ni foam substrate. Due to the synergistic effect between Ni₃S₂ and Fe₃O₄, the Fe₃O₄@Ni₃S₂ heterostructure catalyst demonstrates remarkable catalytic activity under alkaline conditions which is attributed to the highly exposed active sites, adjustment of the d-band center, and the built-in electric field at the interface. The catalyst Fe₃O₄@Ni₃S₂ has low overpotentials of 207 and 217 mV for the OER (oxygen evolution reaction) and 99 and 118 mV for the HER (hydrogen evolution reaction) in alkaline and seawater electrolytes, respectively, allowing it to yield a current density of 10 mA cm⁻². Furthermore, the Fe₃O₄@Ni₃S₂||Fe₃O₄@Ni₃S₂ electrolyzer can achieve a current density of 10 mA cm⁻² for alkaline fresh water and seawater (1 M KOH + seawater) electrolysis at low voltages of 1.57 V and 1.58 V, respectively. This study presents a novel approach for fabricating high-performance multi-interface 3D catalysts for overall water/seawater splitting.

中文翻译：

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操纵 Mott-Schottky 电催化剂中的界面电荷重新分布以实现高性能水/海水分解


界面工程是开发低成本高效电催化剂的有效方法，用于在碱性水或海水环境中生产绿色氢气。在此，我们成功制备了一种界面工程的 Mott-Schottky 异质结构催化剂，即 Fe₃O₄@Ni₃S₂，其中，Ni₃S₂ 纳米片均匀分散在 Fe₃O₄ 花状纳米片的表面，这些纳米片由泡沫镍基底支撑。由于 Ni₃S₂ 和 Fe₃O₄ 之间的协同作用，Fe₃O₄@Ni₃S₂ 异质结构催化剂在碱性条件下表现出显着的催化活性，这归因于高度暴露的活性位点、d 波段中心的调整和界面处的内置电场。催化剂 Fe₃O₄@Ni₃S₂ 在碱性和海水电解质中具有 OER（析氧反应）的 207 和 217 mV 和 HER（析氢反应）的低过电位分别为 99 和 118 mV，使其能够产生 10 mA ^cm-2 的电流密度。此外，Fe₃O₄@Ni₃S₂||Fe₃O₄@Ni₃S₂ 电解槽在 1.57 V 和 1.58 V 的低电压下，碱性淡水和海水（1 M KOH + 海水）电解的电流密度分别为 10 mA ^cm-2。本研究提出了一种用于整体水/海水分解的高性能多界面 3D 催化剂的新方法。