One-step synthesis of zinc oxide-carbon microspheres decorated with multi-voids and carbon nanotubes via spray pyrolysis for enhanced stability in lithium metal anodes

The lithium metal anode has emerged as a promising candidate for future high-energy-density batteries. However, its practical application is hindered by the uncontrollable growth of lithium dendrites. In this study, we developed carbon nanotube (CNT)-decorated ZnO-C microspheres, containing multi-voids, as a lithiophilic host material for a stable lithium metal anode using a one-pot synthesis spray pyrolysis process. These microspheres offer ample space for accommodating lithium metal due to the presence of multi-voids. Additionally, the uniform distribution of ZnO nanocrystals and CNTs facilitates homogeneous lithium nucleation without dendrite formation. To understand the role of ZnO nanocrystals in achieving a stable lithium metal anode, density functional theory (DFT) calculations were employed, which demonstrated superior adsorption energies for lithium atoms as well as favorable electronic properties of the ZnO component. Consequently, the ZnO-C-CNT microspheres exhibit a stable lithium plating/stripping behavior, characterized by high Coulombic efficiency and the maintenance of stable voltage profiles in a symmetric cell configuration. When coupling this anode with the LiNi_0.8Co_0.1Mn_0.1O₂ cathode, the assembled full cell demonstrates excellent cycling stability and high-rate capability, indicating its potential for practical applications.