In-situ fabrication of self-supported cobalt molybdenum sulphide on carbon paper for bifunctional water electrocatalysis

• Published in: Heliyon Vol. 10; no. 10; p. e31108
• Main Authors: Yao, Yuting, Liu, Yuhan, Shin, Juhun, Cai, Shenglin, Zhang, Xinyue, Guo, Zhengxiao, Blackman, Christopher S.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.05.2024; Elsevier
• Subjects: Aerosol assisted chemical vapour deposition; CoMoS phase; Electrochemical water splitting; Heterostructure coupling; Synergistic effect; Aerosol assisted chemical vapour deposition; Electrochemical water splitting; Synergistic effect; CoMoS phase; Heterostructure coupling
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e31108

The fabrication of highly efficient yet stable noble-metal-free bifunctional electrocatalysts that can simultaneously catalyse both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remains challenging. Herein, we employ the heterostructure coupling strategy, showcasing an aerosol-assisted chemical vapour deposition (AACVD) aided synthetic approach for the in-situ growth of cobalt molybdenum sulphide nanocomposites on carbon paper (CoMoS@CP) as a bifunctional electrocatalyst. The AACVD allows the rational incorporation of Co in the Mo–S binary structure, which modulates the morphology of CoMoS@CP, resulting in enhanced HER activity (ŋ10 = 171 mV in acidic and ŋ10 = 177 mV in alkaline conditions). Furthermore, the CoS2 species in the CoMoS@CP ternary structure extends the OER capability, yielding an ŋ100 of 455 mV in 1 M KOH. Lastly, we found that the synergistic effect of the Co–Mo–S interface elevates the bifunctional performance beyond binary counterparts, achieving a low cell voltage (1.70 V at 10 mA cm−2) in overall water splitting test and outstanding catalytic stability (∼90 % performance retention after 50-/30-h continuous operation at 10 and 100 mA cm−2, respectively). This work has opened up a new methodology for the controllable synthesis of self-supported transition metal-based electrocatalysts for applications in overall water splitting.