A bulky and flexible electrocatalyst for efficient hydrogen evolution based on the growth of MoS₂ nanoparticles on carbon nanofiber foam

An advanced hydrogen evolution reaction (HER) electrocatalyst is highly desired for the development of solar water-splitting devices. In this work, we describe the preparation of a flexible, three-dimensional (3D) and durable electrode, which is composed of MoS₂ nanoparticles grown on bacteria-cellulose-derived carbon fiber foam (MoS₂/CNF). The MoS₂/CNF foam was used as a bulky and flexible HER electrocatalyst, exhibiting excellent catalytic activity for a hydrogen evolution reaction in an acidic electrolyte (16 mA cm^-2 at an overpotential of 230 mV). Remarkably, this novel HER electrocatalyst shows a low onset overpotential of 120 mV, a small Tafel slope of 44 mV dec^-1, a high exchange current density of 0.09 mA cm^-2, and a Faradaic efficiency of nearly 100%. This work offers an attractive strategy of preparing bulky and flexible electrocatalyst for large-scale water splitting technology.