Silica-Polypyrrole Hybrids as High-Performance Metal-Free Electrocatalysts for the Hydrogen Evolution Reaction in Neutral Media

Constructing inorganic-organic hybrids with superior properties in terms of water adsorption and activation will lead to catalysts with significantly enhanced electrocatalytic activity in the hydrogen evolution reaction (HER) in environmentally benign neutral media. Herein, we report SiO2-polypyrrole (PPy) hybrid nanotubes supported on carbon fibers (CFs) (SiO2/PPy NTs-CFs) as inexpensive and high-performance electrocatalysts for the HER in neutral media. Because of the strong electronic interactions between SiO2 and PPy, the SiO2 uniquely serves as the centers for water adsorption and activation, and accordingly promotes the HER. The metal-free SiO2/PPy NTs-CFs displayed high catalytic activity in the HER in neutral media, such as a low onset potential and small Tafel slope, as well as excellent long-term durability.