Boosted photogenerated charge carrier separation by synergy of oxygen and phosphorus co-doping of graphitic carbon nitride for efficient 2-chlorophenol photocatalytic degradation

•The oxygen-and-phosphorus co-doped g-C3N4 (OPCN-x) has been prepared via a facile one- step thermal polymerization.•The prepared OPCN exhibits enhanced optical absorption, boosted the separation of photogenerated charge carrier.•DFT calculations revealed the mechanism by the synergistic effect of O and P co-doping regulates band structure and charge distribution.•The OPCN photocatalyst possesses strong adsorption of O2 to generate abundant reactive oxygen species for photocatalytic reaction.