TiO2 encapsulated in Salicylaldehyde-NH2-MIL-101(Cr) for enhanced visible light-driven photodegradation of MB

• TiO2 encapsulated in modified MOF for effective photodegradation was reported for the first time.
• LP(Ti) showed excellent performance for MB degradation under visible light.
• The introduced phenol group in LP(Ti) tripled the MB degradation efficiency.
• The synergy index of the LP(Ti)/visible/H2O2 system was enhanced by 106%.
• The mechanism of LP(Ti)/visible/H2O2 for MB photodegradation was illustrated.

An effective visible light-driven photocatalyst of TiO2 encapsulated in modified MOF was synthesized for the first time and the resulting TiO2@Salicylaldehyde-NH2-MIL-101(Cr) (namely LP(Ti)) was characterized. Then the photodegradation of MB with LP(Ti) was tested. The introduction of salicylaldehyde significantly enhanced the light-absorption properties of LP and LP(Ti), undergoing redshift compared with NH2-MIL-101(Cr) and TiO2@NH2-MIL-101. The LP(Ti) showed an excellent photodegradation efficiency of MB as high as 86% in 60 min of visible-light irradiation with only 5 mg photocatalyst, which was the highest among the tested samples NH2-MIL-101(Cr), TiO2@NH2-MIL-101(Cr), LP, LP(Ti) and Degussa P-25. The LP(Ti)/visible/H2O2 system showed the enhanced synergy index by 106%. The mechanism of the photodegradation of MB with H2O2 over LP(Ti) under the visible light was further illustrated. This work provides a new approach to design MOF encapsulated TiO2 for visible light-induced photodegradation of organic contaminants for the environmental remediation.

Illustration of the MB degradation on LP(Ti) with H2O2 under visible light.Figure optionsDownload as PowerPoint slide