| 摘要： |
Heteroatomic doping (such as N, B, S, P) is one of the most effective strategies to improve the electrochemical performance of carbon-based materials. Herein, 2D phosphorus doped graphdiyne (P-GDY) is prepared via a facile calcination method with phosphoric acid as phosphorus source, and the structure-function relationship of P doping and the electrochemical performance of P-GDY are also investigated using a method combining experiment and density functional theory (DFT) calculations. X-ray photoelectron spectroscopy (XPS) and fourier transform infrared spectroscopy (FTIR) verify that phosphorus (P) is doped in GDY framework via the forms of P-O, P = O and P-C bonds. Raman spectra and Brunauer-Emmett-Teller (BET) results reveal that the P doping creates numerous heteroatomic defects and active sites, causes more hierarchical micro-mesoporous, which provide more storage sites of Li and transmission paths for corresponding ions. Besides, DFT results imply that the most stable geometries can be obtained when the P-containing groups are doped at the benzene in GDY structure, and the doping P = O bonds are beneficial to Li storage. As a result, for P-GDY, enhanced electrochemical performances for lithium-ion batteries are obtained compared with pristine GDY, including higher reversible capacity, improved rate performance, and superior cycling stability. |
