A cobalt porphyrin-bridged covalent triazine polymer-derived electrode for efficient hydrogen production

Abstract

Pronounced compositional regulation and microstructure evolution have a significant influence on hydrogen electrocatalysis. Herein, for the first time, we demonstrate that N,Co-codoped carbon supported Co_5.47N nanoparticles (Co_5.47N/N,Co–C-800) derived from a nitrogen-rich porphyrin-bridged covalent triazine polymer (CoTAPPCC) are an effective electrocatalyst for the HER in 1.0 M KOH when compared to CoCo₂O₄/N,Co–C-900 (pyrolysis at 900 °C) and CoO/N,Co–C-1000 (pyrolysis at 1000 °C). The structural and morphological variations of CoTAPPCC at different heat treatment temperatures were investigated through various spectroscopic techniques. We reveal that electrocatalytic HER activity is temperature- and component-dependent. The overpotentials for Co_5.47N/N,Co–C-800 to reach current densities of 10 and 100 mA cm⁻² were determined to be 76 and 229 mV, respectively, outperforming many other state-of-the-art HER electrocatalysts. This work also sheds light on the influence of calcination temperature on the electrocatalytic HER of final samples.