3D foam-like P, N, S-codoped NCP@CNS as cathode for high-performance Li–O₂ battery

The metal–organic framework (MOFs) derivatives have high specific surface area and multilayer pore structure, which can store more of lithium peroxide and facilitate O₂ diffusion. Three-dimensional (3D) carbon nanosheets can be introduced by chemical blowing method, which can further improve the electrical conductivity. The MOF derivatives are used as a template to heat up the mixture with L-cysteine (LC) and phytic acid (PA) to obtain a foam-like material Ni/Co(PO₃)₂-NCP@CNS. In this process, the carbonization of organic gels and the phosphating of MOFs make the 3D carbon nanosheets incorporate three elements of P, N, and S, which make NCP@CNS with a large specific surface area and the excellent electrical conductivity. Li-O₂ batteries based on NCP@CNS electrode exhibit a high discharge capacity of 23,070 mAh g⁻¹ at 100 mA g⁻¹, an excellent rate capability of 16,296 mAh g⁻¹ at 1.0 A g⁻¹, and a 251 cycle stability under a restricted capacity.