Ultralow-Platinum Supported Polyaniline-MXene via Facile Electrochemical Strategy for Efficient Hydrogen Evolution

The design of ultralow-platinum electrocatalyst with a superior performance is of great interest for hydrogen evolution reaction (HER). Herein, we developed a facile approach of electrochemical deposition that is applicable to construct ultralow-Pt supported polyaniline-Ti 3 C 2 T x MXene electrocatalyst (denoted as Pt/PANI-Ti 3 C 2 T x ). It is found that the aniline monomers and Ti 3 C 2 T x nanoflakes were simultaneously electrodeposited on the surface of carbon paper and formed ordered nanostructures, which efficiently immobilizes more Pt species and promotes the H* conversion. The Pt loadings in the as-designed electrocatalyst is determined to be 2.2 μ g cm ‒2 , which is around two-order of magnification lower than that in the state-of-the-art Pt/C catalyst. While it exhibits excellent HER performance with low applied overpotential of 52 mV at a current density of 10 mA cm ‒2 , a high turnover frequency of 14.13 H 2 s ‒1 and high mass activity of 14 A mg Pt ‒1 , as well as excellent long-term durability. Additionally, density functional theory calculations reveal more favorable H adsorption-desorption by the synergistic effect between Pt and PANI-Ti 3 C 2 T x facilitating hydrogen production.