Synergistic removal of organic pollutants by Co-doped MIL-53(Al) composite through the integrated adsorption/photocatalysis

Co-doped metal organic frameworks (MOFs) were fabricated by a facile route and applied to remove (tetracycline, congo red, methylene blue and rhodamine B) through integrated adsorption and photocatalysis. The assembled MOFs composite exhibited larger SBET (889 ​m2/g), broad light adsorption, and accelerated carrier kinetics, which helped to enhance adsorption and photocatalysis performance. Specifically, nearly 100% TC (40 ​mg/L) could be removed by the Co-MIL-10 within 12 ​min solar-light irradiation, significantly faster than that of solo MIL-53(Al) (82%) and CoAl-LDH (54%), separately. Furthermore the obtained rate constant (0.2064 min−1) was 4.8 times and 9.7 times greater than that of MIL-53(Al) and CoAl-LDH, respectively. The quenching/EPR characterization suggested that photo-generated h+/•O2−/•OH species were responsible for TC oxidation, of which h+ showed the great impact. Cycling experiments verified the robust stability of the MOFs catalyst. As well, an underlying photocatalytic mechanism of the current system was investigated in detail.