Facile Polypyrrole/NASICON (PPy/Na3Fe2(SO4)2(PO4)) Electrode Materials for the Hydrogen Evolution Reaction

Abstract

The synergistic effect of low-cost, noble metal-free, environmentally friendly, and highly electrochemically active electrocatalysts is often used for the hydrogen evolution reaction (HER). Herein, nanocomposites of polypyrrole (PPy) and NASICON-structured Na3Fe2(SO4)2(PO4) (NFS) for an efficient HER have been synthesized by simple chemical oxidative polymerization. The PPy/NFS-5% (optimized ratio) nanocomposite exhibits excellent HER activity in a highly acidic medium, having a considerably low onset overpotential of -26 mV along with a Tafel slope of 101 mV dec-1 and a comparatively low overpotential of -206 mV corresponding to a current density of 10 mA/cm2. The as-synthesized PPy/NFS-5% nanocomposite also offers long-term stability and excellent durability. The superior electrocatalytic activity of PPy/NFS-5% nanocomposite results from the synergism between the conductivity of the PPy matrix and the hydrophilicity of NFS, providing an abundant electrocatalytic active site. The as-synthesized PPy/NFS-5% nanocomposite may find potential in real-world hydrogen production. © 2022 American Chemical Society.