High Conductive Two-Dimensional Covalent Organic Frameworks for Anodes of Lithium-Ion Batteries

Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
H. Yang (West Virginia University), C. Huang (Qingdao Institute of Bioenergy and Bioprocess Technology), and H. Liu (Institute of Chemistry,Chinese Academy of Sciences)
Two-dimensional covalent organic framework (COF) nanosheets based on 5,10,15,20-tetra(4-thiophenephenyl)- porhyrin (TThPP) featuring high conductivity were synthesized using an in-situ chemical oxidative polymerization method. Here, we show for the first time a 2D COF used as the anode for lithium-ion batteries. When used as anode material for lithium ion batteries, the TThPP anode displayed good lithium-ion storage properties with high specific capacities, excellent rate performances, and long cycle lives compared with that of graphitic (372 mAh g−1) and other organic anodes. The reversible capacity is up to 666 mAh g−1. The TThPP also exhibited high energy and power densities of 48.44 Wh kg−1 and 700.36 W kg−1 respectively when used as the anode of a hybrid capacitor. The unique nanosheet morphology of the TThPP anode films provide efficient adsorption sites for Li atoms, short-ended paths for the fast lithium-ion diffusion, and open nanopores for holding electrolyte that contribute to the excellent electrochemical performance.