In this work, a novel CoP/NiCoP heterostructure with hollow nanoflower morphology is designed and constructed. Benefiting from the hollow nanoflower morphology and tuned electronic structure, the heterostructured CoP/NiCoP hollow nanoflowers are demonstrated as both high-performance supercapacitor electrode materials and superior bifunctional electrocatalysts in overall water splitting. The CoP/NiCoP delivers a high capacitance of 1476.6 F g⁻¹ at 1.0 A g⁻¹ and shows enhanced rate capability. The constructed asymmetric supercapacitor achieves a high energy density of 32.4 Wh kg⁻¹ at 800.5 W kg⁻¹ and high power density of 16.5 kW kg⁻¹ at 20.0 Wh kg⁻¹. The CoP/NiCoP hollow nanoflowers are also proven to be remarkable hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) catalyst which achieves the current density of 10.0 mA cm⁻² under an overpotential of 110.4 mV for HER and 310.7 mV for OER with superior stability in alkaline solution. In addition, the constructed CoP/NiCoP||CoP/NiCoP cell with CoP/NiCoP as both cathode material and anode material only requires 1.63 V @ 10.0 mA cm⁻² for overall water splitting. This study sheds lights on the rational design and construction of bimetallic phosphides for both supercapacitor and overall water splitting.

在这项工作中，设计并构建了一种具有空心纳米花形貌的新型CoP/NiCoP异质结构。受益于空心纳米花形态和调整的电子结构，异质结构CoP/NiCoP空心纳米花被证明是高性能超级电容器电极材料和在整体水分解中的优异双功能电催化剂。CoP/NiCoP在 1.0 A g ^{-1下提供 1476.6 F g -1}的高电容，并显示出增强的倍率性能。所构建的非对称超级电容器在800.5 W kg ^{-1时实现了32.4 Wh kg -1}的高能量密度，在20.0 Wh kg ^{-1时实现了16.5 kW kg -1}的高功率密度。CoP/NiCoP空心纳米花也被证明是卓越的析氢反应（HER）和析氧反应（OER）催化剂，其在110.4 mV的HER过电势和310.7 mV的OER过电势下实现了10.0 mA cm -2 的电流密度^。在碱性溶液中具有优异的稳定性。此外，以CoP/NiCoP作为阴极材料和阳极材料构建的CoP/NiCoP||CoP/NiCoP电池仅需要1.63V @ 10.0 mA cm ^-2来进行全部水分解。这项研究揭示了用于超级电容器和整体水分解的双金属磷化物的合理设计和构造。