Abstract In this work, the electrocatalyst systems of CoP nanoparticles confined within carbon nanotubes are presented, which bridge CeO 2 –CoP heterostructures embedded in nitrogen‐doped hollow carbon nanocubes (CoP@CNTs/CeO 2 –CoP@NCs) and further engineered with Pt single atom (Pt–CoP@CNTs/CeO 2 –CoP@NCs). The Pt–CoP@CNTs/CeO 2 –CoP@NCs catalyst exhibits outstanding performance for hydrogen and oxygen evolution in 1.0 m KOH medium. The two‐electrode Pt–CoP@CNTs/CeO 2 –CoP@NCs (−) ||CoP@CNTs/CeO 2 –CoP@NCs (+) configuration reaches a low cell voltage of 1.52 V in 30 wt.% KOH and 1.53 V in 1.0 m KOH. This system further demonstrates exceptionally high mass activity, ≈38.5‐fold greater than that of commercial Pt/C (−) ||RuO 2(+) . The fabricated anion exchange membrane electrolyzer stack provides a stack voltage of 1.71/1.84/2.04 V at 0.5/1/2 A cm −2 in 1.0 m KOH at 60 °C and excellent stability for over 1400 h. The CeO 2 –CoP heterostructures‐sealed nitrogen‐doped hollow carbon nanocubes‐bridged CoP@CNTs architecture owns a hierarchical structure with numerous metallic heterogeneous interfaces and efficient connection between different active phases to ensure abundant active sites, superb conductivity, short electron transfer pathways, and controlled adsorption/desorption of intermediates for rapid OER kinetics. In addition, the incorporation of a small Pt amount into CoP@CNTs/CeO 2 –CoP@NCs generates unique electronic properties to reach high catalytic HER performance, thereby yielding the efficient electrocatalyst systems for sustainable and economically viable water splitting.
Li et al. (Tue,) studied this question.