Realizing high performance bifunctional energy storage devices and electrocatalytic water splitting catalysts through regulated interface engineering of ZnCo 2 O 4 @Co 3 O 4 nanosheets

• Published in: CrystEngComm 2023-08, Vol.25 (34), p.4812-4821
• Main Authors: Miao, Lihua, Sui, Lili, Shen, Xiaoyan, Yang, Dan, Huang, He, Kuang, Ye
• Format: Article
• Language: English
• ISSN: 1466-8033; 1466-8033
• DOI: 10.1039/D3CE00534H

The development and optimization of electrocatalysts is one of the key points to reduce the energy barrier of electrocatalytic water splitting and improve the kinetics of electrocatalytic reactions. It is necessary to develop low-cost, high-performance electrocatalysts with large-scale application prospects. In order to solve this problem, hybrid structured ZnCo 2 O 4 @Co 3 O 4 nanowires are successfully synthesized through hydrothermal synthesis and electrodeposition. As electrocatalysts for water splitting, ZnCo 2 O 4 @Co 3 O 4 can reach a current density of 50 mA cm −2 at an overpotential of 278 mV for the OER and 166 mV@−10 mA cm −2 for the HER, which could be higher than that of single ZnCo 2 O 4 and Co 3 O 4 . At the same time, ZnCo 2 O 4 @Co 3 O 4 samples also exhibit a cell voltage of 1.67 V at a high current density of 50 mA cm −2 and superior durability for 50 h. The fabricated product also showcases a specific capacitance of 1316 F g −1 at 1 A g −1 . Additionally, the assembled device attains a maximum energy density of 47.3 W h kg −1 at a power density of 1126 W kg −1 . Furthermore, density functional theory (DFT) calculation further confirms that the heterostructure can significantly promote Gibbs free energy for hydrogen adsorption. And the significant increase in the density of total states (DOS) also enhances the catalytic activity for the HER.