Mo,Fe-codoped metal phosphide nanosheets derived from Prussian blue analogues for efficient overall water splitting

Xiaoqiang An; Li Quan; Jianqiao Liu; Qingwen Tang; Huachun Lan; Huijuan Liu

doi:10.1016/j.jcis.2022.02.007

Mo,Fe-codoped metal phosphide nanosheets derived from Prussian blue analogues for efficient overall water splitting

J Colloid Interface Sci. 2022 Jun:615:456-464. doi: 10.1016/j.jcis.2022.02.007. Epub 2022 Feb 4.

Authors

Xiaoqiang An¹, Li Quan², Jianqiao Liu², Qingwen Tang¹, Huachun Lan¹, Huijuan Liu³

Affiliations

¹ Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
² Key Laboratory of Material Chemistry for Energy Conversion and Storage, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, Hubei 430074, China.
³ Center for Water and Ecology, State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China. Electronic address: hjliu@tsinghua.edu.cn.

PMID: 35150953
DOI: 10.1016/j.jcis.2022.02.007

Abstract

Designing non-precious electrocatalysts with multiple active centers and durability toward overall water splitting is of great significance for storing renewable energy. This study reports a low-cost Mo, Fe codoped NiCoP_x electrocatalysts derived from Co-Fe Prussian blue analogue and following phosphorization process. Benefitted from the optimized electronic configuration, hierarchical structure and abundant active sites, the Mo,Fe-NiCoP_x/NF electrode has shown competitive oxygen evolution reaction (ƞ₁₀ = 197 mV) and hydrogen evolution reaction performance (ƞ₁₀ = 99 mV) when the current density is 10 mA cm^-2 in 1 M KOH solution. Moreover, the integrated water splitting device assembled by Mo,Fe-NiCoP_x/NF as both anode and cathode only needs a voltage of 1.545 V to reach 10 mA cm^-2. Density functional theory results further confirm that the Mo, Fe codoped heterostructure can synergistically optimize the d-band center and Gibbs free energy during electrocatalytic processes, thus accelerating the kinetics of electrochemical water splitting. This work demonstrates the importance of rational combination of metal doping and interface engineering for advanced catalytic materials.

Keywords: Active sites; Heteroatom doping; Ion-exchange; Overall water splitting; Phosphorization.