Oxygen vacancies – Cu doping junction control of δ-Bi2O3 nanosheets for enhanced photocatalytic nitrogen fixation

Cu-δ-Bi2O3 nanosheets with uniform thickness of approximately 2.7 nm and length about 200 nm for photocatalytic nitrogen fixation and photocatalytic oxidation is achieved by simple hydrothermal method. The 2D ultrathin structure is benefit to the formation of the surface oxygen vacancies, meanwhile the impurity defect is formed due to the substitutive Cu doping of δ-Bi2O3. The as-prepared 5% Cu-δ-Bi2O3 exhibits excellent NH4+ generation rate of 142.8 µmol h−1 g−1 without any sacrificial agent irradiated by visible light. The remarkable photocatalytic ability can be attributed to the ultrafast carriers transfer from the interior to the surface because of 2D ultrathin structure feature, the separation of electrons-holes and molecular chemisorption due to the formation of surface oxygen vacancies and impurity defect.