In-situ synthesis of hybrid nickel cobalt sulfide/carbon nitrogen nanosheet composites as highly efficient bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries. (1st December 2020)

• Record Type: Journal Article
• Authors: He, Jin-Zhong; Niu, Wen-Jun; Wang, Ya-Ping; Sun, Qiao-Qiao; Liu, Ming-Jin; Wang, Kuangye; Liu, Wen-Wu; Liu, Mao-Cheng; Yu, Fu-Cheng; Chueh, Yu-Lun
• Is Part Of: Electrochimica acta. Volume 362(2020)
• Publication Date: 2020-12-01
• Subjects: NiCo2S4/CNNs composites -- Electrocatalyst -- Oxygen reduction reaction -- Oxygen evolution reaction -- Zn-air batteries; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2020.136968
• Languages: English
• ISSNs: 0013-4686

Abstract

ABSTRACT: In this work, an in-situ synthetic, pyrolytic and carbonized method is elaborately demonstrated to prepare the nickel cobalt sulphide (NiCo2 S4 ) nanoparticles (NPs)/carbon nitrogen nanosheets (CNNs) composites as a highly efficient bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries (ZABs). Specifically, the in-situ synthesized NiCo2 S4 NPs confined in cages of CNNs create a well-defined electron transfer hetero-interface with more exposed active sites. The combined NiCo2 S4 NPs with the CNNs generate a synergistic effect, which provides effective electron transfer pathways to enhance the electrocatalytic behaviors, yielding a more positive half-wave potential (0.83 V) for oxygen reduction reaction (ORR) and a lower overpotential (360 mV at 10 mA cm −2 ) for oxygen evolution reaction (OER). As a proof of concept, the equipped ZABs exhibit a high peak power density of 92 mW cm −2 and a superior energy density of 1025 Wh kg −1 with robust cycling stability over 1000 cycles for 180 h, which are better than that of a commercially available Pt/C-RuO2 catalyst. The findings highlight the practical viability of the NiCo2 S4 /CNNs composites in rechargeable ZABs and provide a new approach for the efficient synthesis of bifunctional oxygen electrocatalyst in the future. Graphical abstract: Image, graphical abstract An in-situ synthetic, pyrolytic and carbonized method was elaborately developed to prepare the nickel cobalt sulfide/carbon nitrogen nanosheets (NiCo2 S4 /CNNs) composites as highly efficient bifunctional oxygen electrocatalyst for rechargeable Zn-air batteries (ZABs). The equipped ZABs display a high peak power density (92 mW cm −2 ), yielding superior energy density of 1025 Wh kg −1 with robust cycling stability over 1000 cycles for 180 h, which are better than that of a commercial available Pt/C-RuO2 catalyst.