Optimization by central composite design (CCD)-response surface methodology (RSM) of the highly selective molecularly imprinted Ni and F co-doped TiO2 photocatalyst for photocatalytic degradation of bisoprolol

Molecularly imprinted Ni and F co-doped TiO2 nanoparticles were synthesized via the sol-gel method. The nanoparticles displayed high photocatalytic activity under both sunlight and artificial visible light for degradation of bisoprolol. Characterization of the nanoparticles was carried out using XRD, FE-SEM, TEM, FT-IR, DRS, EDX and BET-BJH. The effects of different operational variables on the photocatalytic activity were optimized using the response surface methodology (RSM). The optimal experimental conditions for achieving the highest photocatalytic efficiency (72.5% by a desirability function value of 1.0) are as follows: pH = 5.9, photocatalyst mass = 83.42 mg, bisoprolol concentration = 16.2 mg L-1, and irradiation time = 137 min. The selectivity of the photocatalyst was investigated against pantoprazole. The excellent photocatalytic activity is attributed to the doping of Ni and F dopants into the TiO2 structure. The investigation of the mechanism of the photocatalytic reaction revealed that the main active species involved in the degradation of bisoprolol are OH radicals.