“…After the modification of phosphide, the absorption edge of Mn 0.67 Co 1.33 P/g‐C 3 N 4 ‐5 sample exhibits a slight blue shift from 425.6 to 417.6 nm, but the visible light absorption is increased distinctly between 460 and 700 nm, which is beneficial for enhancing the photocatalytic performance. In addition, based on the Tauc formula, the band gap value of g‐C 3 N 4 and Mn 0.67 Co 1.33 P/g‐C 3 N 4 ‐5 samples are calculated to be 2.99 and 3.04 eV via plots of ( αhν ) 2 vs ( hν ), respectively (Figure b) . Furthermore, the valence band (VB) and the conduction band (CB) positions of g‐C 3 N 4 and Mn 0.67 Co 1.33 P/g‐C 3 N 4 ‐5 samples can be calculated by E VB = X − E e + 0.5 E g and E CB = E VB − E g , where E VB , E CB , X , E e , and E g are the VB potential, CB potential, the geometric average of the absolute electronegativity of the constituent atoms ( X value of g‐C 3 N 4 is 4.73 eV), the energy of free electrons on the hydrogen scale (4.5 eV vs normal hydrogen electrode [NHE]), and the band gap, respectively .…”