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Slowly Removing Surface Ligand by Aging Enhances the Stability of Pd Nanosheets toward Electron Beam Irradiation and Electrocatalysis |
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| Authors: | Dr Yu Zhang Dr Shaobo Han Dr Shangqian Zhu Dr Ruhui Chen Tiehuai Li Dr Zhiheng Lyu Dr Ming Zhao Prof?Dr Meng Gu Prof?Dr Minhua Shao Prof?Dr Younan Xia |
| Institution: | 1. The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Emory University, 30332 Atlanta, GA, USA
Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China School of Mechanical and Power Engineering, East China University of Science and Technology, 130 Meilong Road, 200237 Shanghai, China;2. Department of Materials Science and Engineering, Southern University of Science and Technology, 518055 Shenzhen, P.?R. China;3. Department of Chemical and Biological Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China;4. School of Chemistry and Biochemistry, Georgia Institute of Technology, 30332 Atlanta, GA, USA;5. The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology, Emory University, 30332 Atlanta, GA, USA |
| Abstract: | Surface ligands play an important role in shape-controlled growth and stabilization of colloidal nanocrystals. Their quick removal tends to cause structural deformation and/or aggregation to the nanocrystals. Herein, we demonstrate that the surface ligand based on poly(vinylpyrrolidone) (PVP) can be slowly removed from Pd nanosheets (NSs, 0.93±0.17 nm in thickness) by simply aging the colloidal suspension. The aged Pd NSs show well-preserved morphology, together with significantly enhanced stability toward both e-beam irradiation and electrocatalysis (e.g., ethanol oxidation). It is revealed that the slow desorption of PVP during aging forces the re-exposed Pd atoms to reorganize, facilitating the surface to transform from being nearly perfect to defect-rich. The resultant Pd NSs with abundant defects no longer rely on surface ligand to stabilize the atomic arrangement and thus show excellent structural and electrochemical stability. This work provides a facile and effective method to maintain the integrity of colloidal nanocrystals by slowly removing the surface ligand. |
| Keywords: | Catalysis Pd Nanosheets Stability Surface Ligand Surface Reconstruction |