High cost precious metal oxides (RuO₂ and IrO₂) electrocatalysts are required to overcome the sluggish kinetics of the oxygen evolution reaction (OER), which severely restricts the scalable application. Herein, we present a versatile anion-exchange based strategy to fabricate various amorphous transition metal oxide hollow nanoprisms with FeCo-MIL-88B template, which exhibit highly efficient OER catalysis in aklaline media. Impressively, a low overpotential of 294 mV at 10 mA cm^-2 with an ultrasmall Tafel slope of 45.1 mV dec^-1 and decent durability can be achieved. More importantly, the underlying origin is unraveled using the in-situ Raman spectroscopy measurement combined with the ex-situ X-ray photoelectron spectroscopy anlysis, where the electrochemically transformed metal hydroxide and oxyhydroxide species could be the real active species. This work provides a universal strategy to construct transition metal oxide hollow nanostructures with enhanced OER activity, which could push forward the advance of noble metal free electrocatalytic water splitting.

需要高价的贵金属氧化物（RuO ₂和IrO ₂）电催化剂来克服氧释放反应（OER）的反应迟缓的动力学，这严重限制了可扩展的应用。在这里，我们提出了一种基于阴离子交换的通用策略，以用FeCo-MIL-88B模板制备各种非晶态过渡金属氧化物空心纳米棱镜，该模板在aklaline介质中具有高效的OER催化作用。令人印象深刻的是，可实现10 mA cm ^-2的294 mV的低过电势和45.1 mV dec ^-1的超小Tafel斜率以及不错的耐久性。更重要的是，使用原位拉曼光谱测量与原位结合可以揭示潜在的起源X射线光电子能谱分析，其中电化学转化的金属氢氧化物和羟基氧化物可能是真正的活性物种。这项工作为构建具有增强的OER活性的过渡金属氧化物空心纳米结构提供了一种通用策略，这可以推动无贵金属电催化水分解的发展。