Ni nanolayers deposited on Nb2CTx/CNT synergistically enhance alkaline bifunctional HER/OER catalytic activity

The escalating global energy crisis has intensified research efforts toward developing heterogeneous structures capable of addressing the sluggish kinetics of the hydrogen evolution reaction and oxygen evolution reaction in electrocatalysis. In this study, a novel strategy for the design of highly efficient bifunctional electrocatalysts was proposed. Uniform Ni nanolayers were successfully deposited on Nb 2 CT x /CNT hybrid supports through a combination of CVD and magnetron sputtering techniques. The resulting Ni/Nb 2 CT x /CNT@NF catalyst demonstrated exceptional electrocatalytic performance in 1 M KOH. For HER, it achieved remarkably low overpotentials of 41 mV@10 mA cm −2 and 196 mV@100 mA cm −2 . Similarly, for OER, the catalyst exhibited outstanding activity with overpotentials of 299 mV@20 mA cm −2 and 337 mV@50 mA cm −2 . Furthermore, the catalyst maintained stable performance at 20 mA cm −2 for 48 h without significant degradation, highlighting its excellent long-term stability. The superior catalytic performance can be attributed to several key factors: (1) The uniform distribution of Ni nanolayers enhances intrinsic conductivity and increases the density of active sites; (2) The incorporation of CNTs expands the reaction interface, facilitating charge and mass transfer; and (3) The electronic interaction between Nb 2 CT x and Ni further optimizes the catalytic kinetics.