Hui Lan, Yan Dengxin, Zhang Xueting, Wu Han, Li Jinze, Li Yuliang
CAS Key Laboratory of Organic Solids, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P.R. China.
University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Angew Chem Int Ed Engl. 2024 Oct 1;63(40):e202410413. doi: 10.1002/anie.202410413. Epub 2024 Aug 16.
The catalytic activity of platinum for CO oxidation depends on the interaction of electron donation and back-donation at the platinum center. Here we demonstrate that the platinum bromine nanoparticles with electron-rich properties on bromine bonded with sp-C in graphdiyne (PtBr NPs/Br-GDY), which is formed by bromine ligand and constitutes an electrocatalyst with a high CO-resistant for methanol oxidation reaction (MOR). The catalyst showed peak mass activity for MOR as high as 10.4 A mg , which is 20.8 times higher than the 20 % Pt/C. The catalyst also showed robust long-term stability with slight current density decay after 100 hours at 35 mA cm. Structural characterization, experimental, and theoretical studies show that the electron donation from bromine makes the surface of platinum catalysts highly electron-rich, and can strengthen the adsorption of CO as well as enhance π back-donation of Pt to weaken the C-O bond to facilitate CO electrooxidation and enhance catalytic performance during MOR. The results highlight the importance of electron-rich structure among active sites in Pt-halogen catalysts and provide detailed insights into the new mechanism of CO electrooxidation to overcome CO poisoning at the Pt center on an orbital level.
铂对一氧化碳氧化的催化活性取决于铂中心的电子给予和反馈给予的相互作用。在此，我们证明了在石墨炔中与sp-C键合的溴上具有富电子性质的铂溴纳米颗粒（PtBr NPs/Br-GDY），它由溴配体形成，构成了一种对甲醇氧化反应（MOR）具有高抗CO能力的电催化剂。该催化剂对MOR的峰值质量活性高达10.4 A mg，比20% Pt/C高20.8倍。该催化剂在35 mA cm下100小时后电流密度略有衰减，还表现出强大的长期稳定性。结构表征、实验和理论研究表明，溴的电子给予使铂催化剂表面高度富电子，能够增强CO的吸附，同时增强Pt的π反馈给予以削弱C-O键，从而促进CO电氧化并提高MOR过程中的催化性能。这些结果突出了Pt-卤素催化剂活性位点中富电子结构的重要性，并在轨道水平上为克服Pt中心的CO中毒提供了CO电氧化新机制的详细见解。
