Facile synthesis of Pr-doped molecularly imprinted TiO2 mesocrystals with high preferential photocatalytic degradation performance

The novel Pr-doped molecularly imprinted TiO2 mesocrystals (Pr-MIP-TMCs) were successfully fabricated by a facile one-pot solvothermal method with Pr(NO3)(3)center dot 6H(2)O as Pr3+ source and 2-sec-butyl-4,6-dinitrophenol (DNBP) as both template molecule and microstructure-director. The morphology, crystallization and structural features of as-prepared different materials including Pr-MIP-TMCs, MIP-TMCs and pristine TMCs were investigated using different techniques for comparison. The results showed that MIP-TMCs and Pr-MIP-TMCs displayed higher adsorption capacity and greater selectivity for DNBP over its structural analogue phenol compared to pristine TMCs due to the conformity between DNBP molecules and the molecular recognition cavities on the surface of the molecularly imprinted photocatalysts. Furthermore, Pr-doped MIP-TMCs showed higher photocatalytic activity than MIP-TMCs under visible irradiation, the higher activity of which could be attributed to strong interaction between the target molecules and imprinted cavities, large adsorption capacity to target molecules, availability of more adsorption sites, narrow band gap energy and efficient separation of photogenerated charges.