Gas-solid phase growth of hierarchical nanoporous nanoplates for water splitting in acidic conditions

Electrochemical production of H₂is hindered by the high cost of noble metal catalysts. Herein, a novel hierarchical nanoporous β-Mo₂C nanoplate was fabricated by a chemical vapor deposition (CVD)-based gas-solid growth strategy for the first time. The parallelogram (or hexagon)-like structure grows directly on conductive substrates and shows uniform nanoporous ligament-pore texture with a pore size of ∼20–40 nm. When evaluated as a binder-free electrode for hydrogen evolution reaction (HER), the hierarchical β-Mo₂C nanoplates exhibit an excellent electrocatalytic performance for HER with a small overpotential of ∼80 mV, a small Tafel slope of 68 mV decade⁻¹and remarkable stability.