Unique CoP Microflower Decorated with Phosphorous‐Enriched PtP<sub>2</sub> onto Nickel Foam with Interfacial Electronic Interactions to Boost Alkaline Water‐Splitting
Wen‐Li Yu, Qichang Li, Weiping Xiao, Jinsong Wang, Bin Dong, Yong‐Ming Chai, Zexing Wu, Lei Wang
Abstract
Abstract The development of stable and efficient electrocatalysts for overall freshwater/seawater water‐splitting has received significant attention. In this study, the fabrication and electrocatalytic properties of phosphorus‐enriched PtP 2 dispersed on CoP (PtP 2 /CoP) for HER and OER in both alkaline fresh/seawater media are described. Physical characterization and density functional theory calculations reveal that strong electronic interfacial interactions between PtP 2 and CoP optimized the reaction kinetics by regulating the adsorption/desorption of intermediates and the cleavage of reactants. Additionally, operando electrochemical impedance spectroscopy reveals that PtP 2 /CoP significantly decreased phase angle with increasing applied potential compared with CoP, demonstrating that the construction of heterostructure provides a faster charge transfer on the surface and in the inner layer. Notably, the catalyst only requires overpotentials of 101 and 298 mV to achieve a benchmark of 100 mA cm −2 in alkaline freshwater for HER and OER. Moreover, the prepared catalyst featured overpotentials of 108 and 330 mV in an alkaline seawater electrolyte. Furthermore, a stable and high‐efficiency water electrolysis operation can be achieved using PtP 2 /CoP as both the anode and cathode (1.63 V@100 mA cm −2 ) coupled with satisfactory durability. This finding provides a deeper comprehension of the interaction of Pt‐less compounds and matrix in electrocatalysis for bifunctional electrocatalysts.