Selective H₂O₂ conversion to hydroxyl radicals in the electron-rich area of hydroxylated C-g-C₃N₄/CuCo–Al₂O₃

Twice the amount of ˙OH as that of the reacted H₂O₂ is produced <italic>via</italic> two electron transfer processes from the electron-rich Cu centers to H₂O₂ and from H₂O to the N atom of the OH–CCN/CuCo–Al₂O₃ composite, which results in extremely high activity for pollutant degradation with a high utilization efficiency of H₂O₂.