Approaching well-dispersed MoS2 assisted with cellulose nanofiber for highly durable hydrogen evolution reaction

Abstract

The agglomeration and low conductivity of molybdenum disulfide (MoS₂) electrocatalysts restrict the presentation of its real intrinsic reaction activity, which leads to challenges for the high-performance hydrogen evolution reaction (HER). Herein, a well-dispersed and superhydrophilic/superaerophobic MoS₂ catalyst with uniform three-dimensional conductive networks have been prepared assisted with cellulose nanofiber (CNF) and carboxylated multi-walled carbon nanotubes (cMWCNT). The resulted CNF/cMWCNT/MoS₂ catalysts present a superhydrophilic/superaerophobic state with contact angles for water and bubble of 0° and 154.1° respectively. This structure effectively disperses MoS₂ nanoparticles through uniform embeddedness and promotes gas-liquid mass transfer via wettability. Benefiting from these optimizations, the CNF/cMWCNT/MoS₂ exhibits better HER performance and a low overpotential (154 mV @ 10 mA/cm²). Encourangingly, CNF/cMWCNT/MoS₂ catalysts have a slight decay of 6.99 % at 10 mA/cm² after 100 h, while the cMWCNT/MoS₂ shows a decay of 35.83 %. This approach using natural CNF for well-dispersed catalysts provides a potential for high-performance HER electrode design.

Keywords: Carbon nanotube; Cellulose nanofiber; Hydrogen evolution; Molybdenum disulfide; Superhydrophilic/superaerophobic state.