Surface-modification of TiO2 with new metalloporphyrins and their photocatalytic activity in the degradation of 4-notrophenol

► A new porphyrin (3) containing a long peripheral substituent with anchoring groups -OH and its Cu(II) (3a), Zn(II) (3b), Ni(II) (3c) metalloporphyrins were synthesized. ► 3a, 3b, 3c-TiO2 photocatalysts were prepared and characterized. ► There exists a weak interaction between TiO2 surface and metalloporphyrin molecules. ► All the 3a, 3b, 3c enhanced the photocatalytic efficiency of bare TiO2 in photodegrading the 4-NP, and 3a-TiO2 exhibited the highest photocatalytic activity.