Metastable Bi3+ self doped NaBiO3 nanosheets were successfully prepared.
Metastable self doped NaBiO3 could generate singlet oxygen.
Metastable self doped NaBiO3 showed enhanced photocatalytic activity.
Visible light enhanced the generation of singlet oxygen from self doped NaBiO3.
Carbamazepine was degraded and mineralized by self doped NaBiO3 irradiated with visible light.