Interface Engineering of N-Doped Cop/Ceo2 Heterostructure for Efficient Overall Water Splitting with Durability Exceeding 1000 H

Abstract

Developing high-efficiency, low-cost, and durable bifunctional electrocatalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is greatly desirable and challenging. Herein, the nitrogen-doped CoP coupled CeO2 heterostructure supported on carbon cloth (N-CoP/CeO2) with outstanding catalytic activity and unprecedented long-term durability is constructed via hydrothermal and subsequent nitridation-phosphorization treatment. The resultant N-CoP/CeO2 exhibits superb catalytic activities for OER and HER, featuring low overpotentials of 215 and 74 mV to afford a current density of 10 mA cm-2 in 1.0 M KOH. Moreover, the N-CoP/CeO2 enables efficient overall water splitting at relatively low cell voltage of 1.52 V with remarkable durability over 1000 h, outperforming most of reported cost-effective electrocatalysts. Theoretical calculations reveal that N-CoP/CeO2 interfaces synergistically accelerate charge transfer and reduce the energetic barrier, thus accelerating the electrocatalytic activity. Additionally, the CeO2 component in N-CoP/CeO2 is regarded as a significant contributor to improving the stability and promoting long-term durability.

Keywords: Bifunctional catalyst, heterostructures, N-CoP/CeO2, Overall water splitting, Long-term durability.