Cr-Doped FeNi-P Nanoparticles Encapsulated into N-Doped Carbon Nanotube as a Robust Bifunctional Catalyst for Efficient Overall Water Splitting

Yiqiang Wu; Xu Tao; Yan Qing; Han Xu; Fan Yang; Sha Luo; Cuihua Tian; Ming Liu; Xihong Lu

doi:10.1002/adma.201900178

Cr-Doped FeNi-P Nanoparticles Encapsulated into N-Doped Carbon Nanotube as a Robust Bifunctional Catalyst for Efficient Overall Water Splitting

Adv Mater. 2019 Apr;31(15):e1900178. doi: 10.1002/adma.201900178. Epub 2019 Feb 21.

Authors

Yiqiang Wu¹, Xu Tao¹, Yan Qing¹, Han Xu¹, Fan Yang², Sha Luo¹, Cuihua Tian¹, Ming Liu¹, Xihong Lu²

Affiliations

¹ Hunan Provincial Collaborative Innovation Center for High-efficiency Utilization of Wood and Bamboo Resources, College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha, 410004, P. R. China.
² MOE of the Key Laboratory of Bioinorganic and Synthetic Chemistry, The Key Lab of Low-carbon Chem and Energy Conservation of Guangdong Province, School of Chemistry, Sun Yat-Sen University, Guangzhou, 510275, P. R. China.

PMID: 30791164
DOI: 10.1002/adma.201900178

Abstract

Exploring high-efficiency, stable, and cost-effective bifunctional electrocatalysts for overall water splitting is greatly desirable and challenging. Herein, a newly designed hybrid catalyst with Cr-doped FeNi-P nanoparticles encapsulated into N-doped carbon nanotubes (Cr-doped FeNi-P/NCN) with unprecedented electrocatalytic activity is developed by a simple one-step heating treatment. The as-synthesized Cr-doped FeNi-P/NCN with moderate Cr doping exhibits admirable oxygen evolution reaction and hydrogen evolution reaction activities with overpotentials of 240 and 190 mV to reach a current density of 10 mA cm^-2 in 1 m KOH solution. When used in overall water splitting as a bifunctional catalyst, it needs only 1.50 V to give a current density of 10 mA cm^-2 , which is superior to its typically integrated Pt/C and RuO₂ counterparts (1.54 V @ 10 mA cm^-2 ). Density functional theory calculation confirms that Cr doping into a FeNi-host can effectively alter the relative Gibbs adsorption energy and reduces the theoretical overpotential. Additionally, the synergetic effects between Cr-doped FeNi-P nanoparticles and NCNs are regarded as significant contributors to accelerate charge transfer and promote electrocatalytic activity in hybrid catalysts.

Keywords: Cr doping; bifunctional catalyst; structural manipulation; transition metals phosphide; water splitting.

Abstract

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