Single-Atom Pt Anchored on Oxygen Vacancy of Monolayer Ti3C2Txfor Superior Hydrogen Evolution

Two-dimensional (2D) MXene-loaded single-atom (SA) catalysts have drawn increasing attention. SAs immobilized on oxygen vacancies (OV) of MXene are predicted to have excellent catalytic performance; however, they have not yet been realized experimentally. Here Pt SAs immobilized on the OVof monolayer Ti3C2Txflakes are constructed by a rapid thermal shock technique under a H2atmosphere. The resultant Ti3C2Tx-PtSAcatalyst exhibits excellent hydrogen evolution reaction (HER) performance, including a small overpotential of 38 mV at 10 mA cm–2, a high mass activity of 23.21 A mgPt–1, and a large turnover frequency of 23.45 s–1at an overpotential of 100 mV. Furthermore, density functional theory calculations demonstrate that anchoring the Pt SA on the OVof Ti3C2Txhelps to decrease the binding energy and the hybridization strength between H atoms and the supports, contributing to rapid hydrogen adsorption–desorption kinetics and high activity for the HER.