Heteroatom coordination induces electric field polarization of single Pt sites to promote hydrogen evolution activity

• Published in: Nanoscale Vol. 13; no. 15; pp. 7134 - 7139
• Main Authors: Peng, Xianyun, Bao, Haihong, Sun, Jiaqiang, Mao, Zhiyong, Qiu, Yuan, Mo, Zhaojun, Zhuo, Longchao, Zhang, Shusheng, Luo, Jun, Liu, Xijun
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 21.04.2021
• Subjects: Catalytic activity; Coordination; Density functional theory; Electric fields; Electrocatalysts; Electronic structure; Hydrogen evolution reactions; Polarization
• ISSN: 2040-3364; 2040-3372; 2040-3372
• DOI: 10.1039/d1nr00795e

Herein, we reported a kind of single Pt site (Pt-SA) stabilized on an MXene support (Pt-SA/MXene) via the formation of Pt-O and Pt-Ti bonds to effectively catalyze the hydrogen evolution reaction (HER). Due to the local electric field polarization derived from its unique asymmetric coordination, Pt-SA/MXene displays remarkably higher catalytic HER activity in an alkaline electrolyte. In detail, the Pt-SA/MXene electrocatalyst only needs a low overpotential of 33 mV to reach a current density of 10 mA cm −2 and maintains the performance over 27 h. Besides, Pt-SA/MXene also has a competitive mass activity, 23.5 A mg Pt −1 , at an overpotential of 100 mV, which is 29.4 times greater than that of the commercial Pt/C counterpart. Density functional theory (DFT) calculations revealed that the polarized electric field could efficiently tailor the electronic structure of Pt-SA/MXene and reduce the energy barrier of adsorption/desorption of the H* intermediate step, further improving its HER catalytic activity. Single Pt atomic sites are stabilized on MXene support via the formation of Pt-O and Pt-Ti bonds. The unique asymmetric coordination environment of single Pt sites induces local electric field polarization, which remarkably enhances HER activity.