LAUSR

A series of graphitic carbon nitrides (g-C3N4) were prepared using different precursors; these g-C3N4-supported CoOx catalysts exhibited different catalytic performances in toluene catalytic combustion reaction. The structure of samples was detected by XRD, TEM, SEM, XPS, H2-TPR, nitrogen adsorption and desorption technique, to build up the structure–performance relationship and uncover the key property of g-C3N4 that mostly influences the catalytic performance of CoOx/g-C3N4. CoOx with average particle size of 12.7 nm supported on g-C3N4 prepared by dicyandiamide showed better catalytic performance than on other supports, 100% toluene conversion could be achieved at ~ 285 °C, characterization results showed that Co was directly connected with N, and the integrity of g-C3N4 sheet affects the dispersion of CoOx; the content of sp2-N (within C=N–C structure) determines the interaction between g-C3N4 and CoOx; these two factors together affect the performance of CoOx/g-C3N4 catalysts in the catalytic combustion of toluene.