Li Xinzhe, Fang Yiyun, Wang Jun, Fang Hanyan, Xi Shibo, Zhao Xiaoxu, Xu Danyun, Xu Haomin, Yu Wei, Hai Xiao, Chen Cheng, Yao Chuanhao, Tao Hua Bing, Howe Alexander G R, Pennycook Stephen J, Liu Bin, Lu Jiong, Su Chenliang
SZU-NUS Collaborative Center and International Collaborative Laboratory of 2D Materials for Optoelectronic Science and Technology of Ministry of Education, Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, Guangdong, China.
Department of Chemistry, National University of Singapore, Singapore, Singapore.
Nat Commun. 2021 Apr 21;12(1):2351. doi: 10.1038/s41467-021-22681-4.
Exposing and stabilizing undercoordinated platinum (Pt) sites and therefore optimizing their adsorption to reactive intermediates offers a desirable strategy to develop highly efficient Pt-based electrocatalysts. However, preparation of atomically controllable Pt-based model catalysts to understand the correlation between electronic structure, adsorption energy, and catalytic properties of atomic Pt sites is still challenging. Herein we report the atomically thin two-dimensional PtTe nanosheets with well-dispersed single atomic Te vacancies (Te-SAVs) and atomically well-defined undercoordinated Pt sites as a model electrocatalyst. A controlled thermal treatment drives the migration of the Te-SAVs to form thermodynamically stabilized, ordered Te-SAV clusters, which decreases both the density of states of undercoordinated Pt sites around the Fermi level and the interacting orbital volume of Pt sites. As a result, the binding strength of atomically defined Pt active sites to H intermediates is effectively reduced, which renders PtTe nanosheets highly active and stable in hydrogen evolution reaction.
暴露并稳定配位不足的铂（Pt）位点，从而优化其对反应中间体的吸附，为开发高效的铂基电催化剂提供了一种理想的策略。然而，制备原子可控的铂基模型催化剂以了解原子铂位点的电子结构、吸附能和催化性能之间的相关性仍然具有挑战性。在此，我们报道了具有良好分散的单原子碲空位（Te-SAVs）和原子明确的配位不足的铂位点的原子级薄二维PtTe纳米片作为模型电催化剂。可控的热处理驱动Te-SAVs迁移形成热力学稳定的有序Te-SAV簇，这降低了费米能级周围配位不足的铂位点的态密度以及铂位点的相互作用轨道体积。结果，原子定义的铂活性位点与H中间体的结合强度有效降低，这使得PtTe纳米片在析氢反应中具有高活性和稳定性。
