Coupling effect and electronic modulation for synergistically enhanced overall alkaline water splitting on bifunctional Fe-doped CoBi/CoP nanoneedle arrays

Yihua Cao; Xueli Yin; Yonghao Gan; Ying Ye; Run Cai; Bo Feng; Qi Wang; Xiaoping Dai; Xin Zhang

doi:10.1016/j.jcis.2023.08.175

Coupling effect and electronic modulation for synergistically enhanced overall alkaline water splitting on bifunctional Fe-doped CoB_i/CoP nanoneedle arrays

J Colloid Interface Sci. 2023 Dec 15;652(Pt B):1703-1711. doi: 10.1016/j.jcis.2023.08.175. Epub 2023 Aug 29.

Authors

Yihua Cao¹, Xueli Yin¹, Yonghao Gan¹, Ying Ye¹, Run Cai¹, Bo Feng¹, Qi Wang¹, Xiaoping Dai², Xin Zhang¹

Affiliations

¹ College of Chemical Engineering and Environment, China University of Petroleum-Beijing, State Key Laboratory of Heavy Oil Processing, Beijing 102249, China.
² College of Chemical Engineering and Environment, China University of Petroleum-Beijing, State Key Laboratory of Heavy Oil Processing, Beijing 102249, China. Electronic address: daixp@cup.edu.cn.

PMID: 37672973
DOI: 10.1016/j.jcis.2023.08.175

Abstract

Designing bifunctional electrocatalysts with high efficiency and low cost for water splitting is urgently required for the production of green hydrogen. Herein, a bifunctional iron-doped cobalt borate/cobalt phosphide hybrid supported on nickel foam (Fe-CoB_i/CoP/NF) was fabricated via hydrothermal and phosphating process. Benefit from the unique nanoneedle architecture for faster mass transfer, the existence of borate on CoB_i for accelerating proton transfer, the moderate adsorption of H* species on CoP, Fe doping and the synergistic effect between CoB_i and CoP, Fe-CoB_i/CoP/NF hybrid exhibits a low overpotential of 137 mV and 260 mV at 100 mA cm^-2 for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), respectively. Moreover, Fe-CoB_i/CoP/NF||Fe-CoB_i/CoP/NF also presents a low cell potential of 1.65 V@100 mA cm^-2 for overall alkaline water splitting and excellent durability (128 h) without decay. This work provides a new insight into the design of bifunctional electrocatalysts simultaneously through the morphological engineering and heteroatomic doping.

Keywords: Bifunctional electrocatalysts; CoB(i)/CoP hybrid; Electron modulation; Fe doping; Synergistic effect.