Pore size distribution dependent controlling selective degradation of binary dye effluent

Herein, mesoporous and microporous strontium titanate (STO) were prepared by facile hydrothermal process using carboxymethyl cellulose (CMC) and cetyltrimethyl ammonium bromide (CTAB) as controlling agent. Effect of different amounts of agents to crystalline, morphology and pore size (distribution) was detected. Specific surface area of mesoporous STO (CMC-STO) is ranging from 24.40 m2/g to 56.90 m2/g. In contrast, microporous STO (CTAB-STO) has specific surface area between 9.54 m2/g to 14.57 m2/g. The average pore sizes are around 10 nm or prior 10-nm for CMC-STO samples. Nevertheless, CTAB-STO has the average pore size with around 1.90 nm. Moreover, X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy and nitrogen isothermal adsorption curve demonstrate the effects of CMC and CTAB on crystalline, morphology, surface groups and average pore size (pore distribution). Binary dye mixture effluent was used to test the selective photocatalytic performance. Mesoporous STO (CMC-STO) presents larger selectivity ratio (α) than that of microporous STO (CTAB-STO). Pore size and distribution was analyzed and illustrated for selective photodegradation. Pore size distribution dependent of binary dye selectively photocatalytic degradation was demonstrated. Concentrations and dye mixture ratios adsorption/desorption and photodegradation are demonstrated selective degradation. Results suggest mesoporous STO has better selective photodegradation performance to MB than pristine or microporous STO. Simultaneously, controlling distribution of pore size is beneficial to selective photodegradation of dye mixture.