Visible light Bi2S3/Bi2O3/Bi2O2CO3 photocatalyst for effective degradation of organic pollutions

Bi2S3/Bi2O3/Bi2O2CO3 photocatalyst was successfully synthesized by combining the rational heat-treatment process and ion exchange technique. These composites exhibited superior photocatalytic activities for organic contaminants (formaldehyde gas, methyl orange and phenol) degradation under the visible light irradiation. These catalysts could eliminate more than 99% of formaldehyde gas within 100 min, which is considerably higher than those of pure Bi2O2CO3 (10.9%) and Bi2O3/Bi2O2CO3 (23.6%) samples at the same condition. Furthermore, these as-prepared Bi2S3/Bi2O3/Bi2O2CO3 composites also show excellent photocatalytic performance for methyl orange and phenol removing as well as good stability. The highly improved performance of the composites can be ascribed to the increased light absorption and efficient charge separation. In addition, the photocatalytic process is mainly governed by the superoxide and the holes rather than the hydroxyl radicals. These features suggest the current heterostructured photocatalysts can be applied in environmental remediation and waste water treatment.