Developing a facile approach based on transition metal-based Prussian blue (PB) and its analogues (PBAs) with core–shell nanostructure is a very promising choice for constructing cost-effective electrocatalysts for oxygen evolution reaction (OER). Herein, a bimetallic core–shell structure with open cages of Fe-doped CoP (Fe-CoP cage) has been synthesized using CoFe-PBA cage-4 as precursor through a facile hydrothermal method and following phosphating process. Interestingly, there is an open hole in each face center of Fe-CoP cage, which suggests the more exposure of active sites for OER. Electrochemical measurements show that Fe-CoP cage can afford a current density of 10 mA cm⁻² at a low overpotential (300 mV), which is better than that of RuO₂. The excellent performance can be attributed to Fe doping composition and unique open-cage core–shell structure. The synergistic effect derived from bimetallic active for OER has been discussed. And its great catalytic stability has been evaluated via 1000 cycles of CV and chronoamperometry measurement. This work provides a potential method to design multiple transitional metal-doping electrocatalysts with complex framework derived from PBAs for water splitting.

开发一种基于过渡金属的普鲁士蓝（PB）及其类似物（PBA）并具有核-壳纳米结构的简便方法，对于构建用于氧释放反应（OER）的具有成本效益的电催化剂是一个非常有希望的选择。在这里，通过方便的水热法并随后进行了磷化处理，以CoFe-PBA笼4为前体，合成了带有Fe掺杂CoP的开放笼的双金属核-壳结构（Fe-CoP笼）。有趣的是，Fe-CoP笼的每个面中心都有一个开孔，这表明OER的活性部位暴露更多。电化学测量表明，Fe-CoP笼可以在低过电势（300 mV）下提供10 mA cm ^-2的电流密度，这比RuO ₂更好。优异的性能归因于铁掺杂成分和独特的开笼核-壳结构。讨论了双金属活性物对OER的协同作用。通过1000个CV循环和计时电流法测量，评估了其出色的催化稳定性。这项工作提供了一种潜在的方法，用于设计具有复杂骨架的多种过渡金属掺杂电催化剂，这些骨架衍生自用于水分解的PBA。