Lignosulfonate-assisted in situ synthesis of Co9S8-Ni3S2 heterojunctions encapsulated by S/N co-doped biochar for efficient water oxidation

Xuliang Lin; Lijing Xue; Bowen Liu; Xueqing Qiu; Jianglin Liu; Xiaofei Wang; Yi Qi; Yanlin Qin

doi:10.1016/j.jcis.2023.04.070

Lignosulfonate-assisted in situ synthesis of Co₉S₈-Ni₃S₂ heterojunctions encapsulated by S/N co-doped biochar for efficient water oxidation

J Colloid Interface Sci. 2023 Aug 15:644:295-303. doi: 10.1016/j.jcis.2023.04.070. Epub 2023 Apr 20.

Authors

Xuliang Lin¹, Lijing Xue², Bowen Liu², Xueqing Qiu¹, Jianglin Liu², Xiaofei Wang³, Yi Qi², Yanlin Qin⁴

Affiliations

¹ School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, China; Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
² School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, China.
³ School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, China. Electronic address: wxfeifei@gdut.edu.cn.
⁴ School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou 510006, Guangdong, China; Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, Guangdong University of Technology, Guangzhou 510006, Guangdong, China. Electronic address: ylqin@gdut.edu.cn.

PMID: 37120878
DOI: 10.1016/j.jcis.2023.04.070

Abstract

The development of highly active and stable earth-rich electrocatalysts remains a major challenge to release the reliance on noble metal catalysts in sustainable (electro)chemical processes. In this work, metal sulfides encapsulated with S/N co-doped carbon were synthesized with a one-step pyrolysis strategy, where S was introduced during the self-assembly process of sodium lignosulfonate. Due to the precise coordination of Ni and Co ions with lignosulfonate, an intense-interacted Co₉S₈-Ni₃S₂ heterojunction was formed inside the carbon shell, causing the redistribution of electrons. An overpotential as low as 200 mV was obtained over Co₉S₈-Ni₃S₂@SNC to reach a current density of 10 mA cm^-2. Only a slight increase of 14.4 mV was observed in a 50 h chronoamperometric stability test. Density functional theory (DFT) calculations showed that Co₉S₈-Ni₃S₂ heterojunctions encapsulated with S/N co-doped carbon can optimize the electronic structure, lower the reaction energy barrier, and improve the OER reaction activity. This work provides a novel strategy for constructing highly efficient and sustainable metal sulfide heterojunction catalysts with the assistance of lignosulfonate biomass.

Keywords: Biochar; Co(9)S(8)–Ni(3)S(2) heterojunction; Lignosulfonate; Oxygen evolution reaction.