Molybdenum oxide nanoporous asymmetric membranes for high-capacity lithium ion battery anode

The cycling performance of high-capacity lithium ion battery anodes can be significantly improved by adopting 3D nanoporous structures that can efficiently accommodate large volume changes during lithiation and de-lithiation. In this study, various molybdenum oxide nanoporous asymmetric membranes were fabricated on a large scale via a spontaneous non-solvent-induced phase separation process. We explored the effects of polymer precursor, membrane geometry, and annealing condition on the porosity, composition, and electrochemical properties of the membranes as lithium ion battery anodes. We demonstrate that 97% initial capacity of MoO₂ planar asymmetric membrane electrode can be retained in 165 cycles at 120 mA g⁻¹. 74% initial capacity can be maintained while the current density is increased from 60 to 480 mA g⁻¹. This efficient and scalable process to prepare molybdenum oxide-based LIB anode provides another alternative to enhance the electrochemical performance of transition metal oxide anodes at a relatively low fabrication cost. Graphic abstract: [Figure not available: see fulltext.].