Exploring effective electrocatalysts is a crucial requirement for boosting the efficiency of water splitting to obtain clean fuels. Here, a self‐templating strategy is reported to synthesize Ni–Fe mixed diselenide cubic nanocages for the electrocatalytic oxygen evolution reaction (OER). The diselenide nanocages are derived from corresponding Prussian‐blue analog nanocages, which are first obtained by treating the nanocube precursor with a site‐selective ammonia etchant. The resulting Ni–Fe mixed diselenide nanocages perform as a superior OER electrocatalyst, which affords a current density of 10 mA cm⁻² at a small overpotential of 240 mV; a high current density, mass activity, and turnover frequency of 100 mA cm⁻², 1000 A g⁻¹, and 0.58 s⁻¹, respectively, at the overpotential of 270 mV; a Tafel slope as small as 24 mV dec⁻¹; and excellent stability in alkaline medium.

中文翻译：

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Ni-Fe混合二硒化物纳米笼的形成作为一种优良的析氧电催化剂

探索有效的电催化剂是提高水分解效率以获得清洁燃料的关键要求。在这里，据报道有一种自我模板化策略可以合成Ni-Fe混合二硒化物立方纳米笼，用于电催化氧释放反应（OER）。二硒化物纳米笼是从相应的普鲁士蓝类似物纳米笼中衍生出来的，它们首先通过用定域选择性氨蚀刻剂处理纳米立方体前体而获得。所得的Ni-Fe混合二硒化物纳米笼可作为优异的OER电催化剂，在240 mV的小超电势下可提供10 mA cm ^-2的电流密度。高电流密度，质量活度和周转频率分别为100 mA cm ^-2，1000 A g ^-1和0.58 s ^-1分别在270 mV的超电势下; Tafel斜率小到24 mV dec ^-1 ; 在碱性介质中具有出色的稳定性。