Ultra-small Ru0-loaded carbon nanotubes for highly efficient electrocatalytic H2 production over a wide pH range

The design of highly efficient catalysts applied in a wide pH range for hydrogen evolution reaction (HER) is still very challengeable. Herein, a rapid Joule heating method has been applied to deposit Ru nanoparticles onto carbon nanotubes (Ru/CNTs). Owing to the rapid heating and cooling processes during the Joule heating treatment, the lattice was disordered with exposure of massive reactive sites for HER. As tested, Ru/CNTs showed outstanding activity in HER in a wide pH range. It only required an overpotential of 21 mV and 9 mV at 10 mA cm −2 for HER in 0.5 M H 2 SO 4 and 1 M KOH, specifically. The overpotential required to achieve a current density of 1 A cm −2 in 0.5 M H 2 SO 4 and 1 M KOH was 162 mV and 360 mV, respectively. The excellent performance of Ru/CNTs was comparable to commercial Pt/C catalyst. Furthermore, using the manufactured Ru/CNTs, a homemade anion-exchange membrane AEM electrolyzer was assembled. It only required 1.87 V to reach 100 mA cm −2 with nearly 100% Faraday efficiency. This work provided a novel method to prepare Ru nanoparticles onto carbon nanotubes by a rapid Joule heating treatment for advanced HER activity in a wide pH range.