One-time sintering process to modify xLi2MnO3 (1-x)LiMO2 hollow architecture and studying their enhanced electrochemical performances

To solve the critical problems of lithium rich cathode materials, e.g., structure instability and short cycle life, we have successfully prepared a ZrO2-coated and Zr-doping xLi(2)MnO(3)center dot(1-x)LiMO2 hollow architecture via one-time sintering process. The modified structural materials as lithium-ion cathodes present good structural stability and superior cycle performance in LIBs. The discharge capacity of the ZrO2-coated and Zr-doped hollow pristine is 220 mAh g(-1) at the 20th cycle at 0.2 C (discharge capacity loss, 2.7%) and 150 mAh g(-1) at the 100th cycle at 1 C (discharge capacity loss, 17.7%), respectively. However, hollow pristine electrode only delivers 203 mAh g(-1) at the 20th cycle at 0.2 C and 124 mAh g(-1) at the 100th cycle at 1 C, respectively, and the corresponding to capacity retention is 92.2% and 72.8%, respectively. Diffusion coefficients of modified hollow pristine electrode are much higher than that of hollow pristine electrode after 100 cycles (approach to 1.4 times). In addition, we simulate the adsorption reaction of HF on the surface of ZrO2-coated layer by the first-principles theory. The calculations prove that the adsorption energy of HF on the surface of ZrO2-coated layer is about -1.699 eV, and the ZrO2-coated layer could protect the hollow spherical xLi(2)MnO(3)center dot(1-x)LiMO2 from erosion by HF. Our results would be applicable for systematic amelioration of high-performance lithium rich material for anode with the respect of practical application. (C) 2020 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved.