Construction of Hierarchical PdAgAu Nanorings/MXene–GO Electrocatalysts for Efficient and Ultrastable Hydrogen Evolution Reaction

Abstract

High overpotential and poor long‐term operation stability of electrocatalysts are two major barriers for the hydrogen evolution reaction (HER). Herein, 2D ultrathin PdAgAu nanorings are synthesized and further self‐assembled on Ti2CTx–graphene oxide (GO) heterostructure for efficiently boosting HER. The best candidate, Pd50Ag31Au19/Ti2CTx–GO electrocatalyst, can initiate hydrogen evolution at an overpotential of 90 mV at 10 mA cm−2 and exhibits the lowest Tafel slope of 75 mV dec−1 as well as the highest mass activity of 284.4 mA mg−1Pd at −100 mV, in comparison with those of Pd50Ag31Au19/Ti2CTx, Pd50Ag31Au19/GO, and commercial Pd/C. Most remarkably, impressive long‐term stability is achieved even after a 112 h chronoamperometric test. The great performance of Pd50Ag31Au19/Ti2CTx–GO electrocatalyst can be attributed to the advantageous synergistic effect among the morphological modulation, composition optimization, and strong metal–support interaction effect between the Pd50Ag31Au19 nanorings and Ti2CTx–GO support.

In situ growth engineering of ultrathin dendritic PdNi nanosheets on nitrogen-doped V2CTx MXenes for efficient hydrogen evolution

“…The reaction follows the Volmer–Heyrovsky mechanism, where the Heyrovsky reaction acts as the rate-determining step. 68,69…”