The Interface Engineering Strategy Coupling Tailored D-Band Center of Cop Nanosheet Arrays for Boosting Urea-Rich Water Splitting

It’s highly desirable but still challenging to design bifunctional non-noble metal electrocatalysts for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) with high activity and boosted mass transport, especially under large-current densities. Hence, a novel 3D reticular heterostructure nanosheet arrays are fabricated (Ni2P/CoP/C-F) through coupling the C-F chemical bonding engineering to realize urea-rich water electrolysis. The formation of C-F bond can effectively enhance the conductivity and stability of Ni2P/CoP heterojunctions along with possible changes in surface hydrophobicity to accelerate release of generated bubbles under large-current densities. Benefiting from tailored d-band center of CoP nanosheet arrays and well-designed hydrophilic-superaerophobic feature, the elaborated Ni2P/CoP/C-F electrode shows brilliant electrocatalytic HER (140 mV) and UOR (251 mV) performance at 100 mA cm-2 current density. Meanwhile, the assembled alkaline urea-rich water electrolyzer with Ni2P/CoP/C-F as both the cathode and anode present ultralow cell voltages of 1.57 V to achieve 100 mA cm-2 with long-time stability. This work will promote research interest in material design for energy conversion technologies and urea-assisted hydrogen production.