Recycling Spent LiCoO ₂ Battery as a High?efficient Lithium?doped Graphitic Carbon Nitride/Co ₃ O ₄ Composite Photocatalyst and Its Synergistic Photocatalytic Mechanism

The ever-increasing quantity of spent lithium-ion batteries (LIBs) is both a potential environmental pollutant and valuable resource. LIBs recycling mainly aimed at the separation elements. Some issues still exist in these processes such as high energy consumption complex procedures. This study avoided element proposed facile approach to transform LiCoO2 electrode into lithium (Li)-doped graphitic carbon nitride (g-C3N4)/Co3O4 composite photocatalyst through one-pot situ thermal reduction. During process, melamine served reductant for decomposition raw material g-C3N4 production. Li was doped generated Co3O4 integrated, forming Li-doped g-C3N4/Co3O4 photocatalyst. special exhibited an enhanced photocatalytic performance, its H2 production RhB degradation rates were 8.7 6.8 times higher than those g-C3N4. experiments combined with DFT calculation revealed that efficiency ascribed synergy effect doping integrating, which extended visible light absorption (450–900 nm) facilitated charge transfer separation. transforms waste high-efficient catalyst, realizing high-valued utilization protection.