Enhanced •OH generation and pollutants removal by framework Cu doped LaAlO3/Al2O3

Highly dispersed framework Cu+/Cu2+ containing LaAlO3/Al2O3 (La-Cu-Al) was synthesized by a solid-liquid mixed sol-gel method. Excessive Al2O3 was confirmed to be necessary for the formation of LaAlO3. The NMR, EXAFS, FTIR and element mapping results revealed that Cu+/Cu2+ preferred to substitute octahedral Al sites and bonded by Cu-O-Al in the lattice of LaAlO3. Compared to La2CuO4, CuAl2O4 and other reported Fenton-like catalysts, La-Cu-Al was more efficient to mineralize refractory pollutants at a wide pH range of 4.0-10.0. More single electrons around Cu center and octahedral Cu+ were confirmed to be responsible for the effective reduction of H2O2 into powerful •OH. Moreover, organic pollutants as electron donors could interact with surface Cu to accelerate Cu2+/Cu+ cycle and affect O-O bond of H2O2 on La-Cu-Al surface, further promoting the reduction of H2O2 into •OH. These processes resulted in the high H2O2 utilization and the highly efficient removal of pollutants on La-Cu-Al.