Ionic liquid promoted synthesis of nitrogen, phosphorus, and fluorine triple-doped mesoporous carbon as metal-free electrocatalyst for oxygen reduction reaction

Recently, heteroatom-doped carbon has been widely used in various fields because of their inexpensive and abundant resources, especially in oxygen reduction reaction. Here, the 1-butyl-3-methlyimidazolium hexafluorophosphate (BmimPF(6)) is explored as the precursor to offer phosphorus and fluorine, and melamine as a supporter to provide nitrogen. The N, P, F-tridoped mesoporous carbons are obtained by pyrolyzing the homogeneous mixture of melamine and BmimPF(6), without any post-processing. This composition of the carbon can be used as a potential metal-free electrocatalyst for oxygen reduction reaction (ORR). Notably, the optimized N, P, and F tri-doped mesoporous carbon obtained at 900 degrees C, exhibits good electrocatalytic performance for ORR, with high electron-transfer number, great methanol crossover tolerance, and outstanding durability. This work may provide a new case to synthesis heteroatom-tridoped carbon for energy conversion and storage.