Exploring the electrocatalytic prowess of a synergistic 1T-MoS 2 -metallic Ni composite towards alkaline hydrogen evolution

• Published in: Materials advances Vol. 5; no. 7; pp. 2805 - 2817
• Main Authors: Roy, Avishek, Mondal, Ayan, Inta, Harish Reddy, Ghosh, Sourav, Paliwal, Khushboo S, Debnath, Soumalya, Valsan, Ajith Ambattuparambil, Mahalingam, Venkataramanan
• Format: Journal Article
• Language: English
• Published: 02-04-2024
• ISSN: 2633-5409; 2633-5409
• DOI: 10.1039/D3MA01077E

Designing of suitable electrocatalysts for efficient alkaline hydrogen evolution reaction (HER) is a challenging task owing to the additional energy consumption to disintegrate the H–OH bond in the Volmer step. Under these circumstances, strong synergistic interactions between Ni/Co derivatives with 1T-MoS
2
can frequently accelerate the alkaline HER. This study addresses the challenge of designing efficient electrocatalysts for the alkaline HER, focusing on minimizing additional energy consumption during the Volmer step. A composite structure, 1T-MoS
2
–Ni(18), was synthesized using 1T-MoS
2
and metallic Ni for effective alkaline HER catalysis. Rigorous physical characterization confirmed the formation of an interfacial structure between 1T-MoS
2
and metallic Ni. The resulting composite exhibited very good alkaline HER performance, requiring only a 120 mV overpotential for a standard 10 mA cm
−2
geo
current density. The improved performance was attributed to feasible water dissociation over the metallic Ni promoter, facile electron migration kinetics through the interfacial structure, and enhanced per-site activity. In addition, for the practical execution of an alkaline electrolyzer, NiS nanoparticles were synthesized as an OER catalyst, exhibiting only a 310 mV overpotential (1.54 V
vs
. RHE) to attain a 10 mA cm
−2
geo
current density. The alkaline electrolyzer, (NiS (+)||1T-MoS
2
–Ni(18) (−)), delivered a 1.68 V cell potential to sustain a 10 mA cm
−2
geo
current density with excellent stability for up to 48 h.