Reactive surface intermediates over Ni-grafted TiO2 nanotube arrays towards hydrogen evolution reaction in alkaline and chloride media

In this study, the Ni nanoparticles grafted TiO2 nanotubes electrode improved by surface reconstruction (s-Ni/TiO2/Ti) shows the facile hydrogen evolution reaction (HER) in the alkaline and chloride solutions. Nickel nanoparticles were electrochemically grafted on the anodic TiO2 nanotubes under different conditions. The heat treatment of TiO2 nanotubes contributes to the enhancement of electrical conductivity and template adherence. The surface reconstruction is indicated to create heterojunction intermediates, Ni(OH)2 and NiOOH, on the surface of Ni nanoparticles. An extremely low overpotential of 126 mV is required for HER on the s-Ni/TiO2/Ti electrode in 1.0 M KOH solution, showing higher activity than Pt/C. Besides, the developed electrode exhibits an overpotential of 127 mV for HER in 1.0 M KOH thorn 0.5 M NaCl solution. The long-term stability over 100 h suggests a highly active and inexpensive material choice for substituting the precious electrocatalysts in corrosive media such as seawater. & COPY; 2023 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study investigates the improved Ni nanoparticles grafted TiO2 nanotubes electrode with surface reconstruction for the facile hydrogen evolution reaction (HER) in alkaline and chloride solutions. The surface reconstruction creates heterojunction intermediates on the Ni nanoparticles and contributes to the low overpotential of the electrode in 1.0 M KOH solution. The electrode also shows good HER performance in acidic NaCl solution and exhibits long-term stability, making it a promising alternative to precious electrocatalysts in corrosive media.