Facile hydrothermal synthesis of high-performance GQD-CuO microflower composite anode for lithium-ion batteries

Copper oxide (CuO) has attracted substantial interest as a potential anode material for lithium-ion batteries (LIBs) because of its high theoretical capacity, non-toxicity, low cost, and abundance. However, the practical application of CuO as an anode is limited by challenges such as high charge-transfer resistance, low electrical conductivity, and limited cycle stability. An effective approach to addressing these issues involves incorporating carbon-based materials but this requires complex synthesis processes. In this work, we propose an efficient synthesis method for the preparation of a graphene quantum dot (GQD)-CuO microflower (MF) composite film (G-CuO MF) via a one-pot hydrothermal process. The synergy between the high specific surface area of CuO MFs and the fast transportation of Li⁺ ions provided by GQDs boosts Li⁺ ion storage. The G-CuO MF composite anode exhibits high reversible capacity and long-term cycling stability.