Authors: Yunyun Xu, Hao Gong, Hao Ren, Xiaoli Fan, Peng Li, Tengfei Zhang, Kun Chang, Tao Wang, Jianping He
Published: 2022-09-26
Source: Full article
AbstractThe lithium‐carbon dioxide (Li‐CO2) battery as a novel metal‐air battery has a high specific energy density and unique CO2 conversion ability. However, its further development is limited by incomplete product decomposition resulting in poor cycling and rate performance. In this work, Cu‐tetra(4‐carboxyphenyl) porphyrin (Cu‐TCPP) nanosheets are prepared through the solvothermal method successfully. An efficient Li‐CO2 battery with Cu‐TCPP as catalyst achieves a high discharge capacity of 20393 mAh g−1 at 100 mA g−1, a long‐life cycle of 123 at 500 mA g−1, and a lower overpotential of 1.8 V at 2000 mA g−1. Density functional theory calculation reveals that Cu‐TCPP has higher adsorption energy of CO2 and Li2CO3 compared with TCPP, and a large number of electrons gather near the Cu‐N4 active sites in Cu‐TCPP. Therefore, the excellent CO2 capture ability of the porphyrin ligand and the synergic catalytic effect of Cu atom in Cu‐TCPP promote the thermodynamics and kinetics of CO2 reduction and evolution processes.