Photodegradation of aqueous bisphenol A using boric acid-doped titanium dioxide

A high-photoactivity boric acid-doped titanium dioxide (B-doped TiO₂) photocatalyst of the degradation of aqueous bisphenol A (BPA) under sunlight was synthesized and characterized by scanning electron microscope, X-ray photoelectron spectroscopy and UV-vis diffuse reflectance. The band gap energies of TiO₂ and B-doped TiO₂ (B/Ti mole ratio = 0.2%) were 3.01 and 2.98, showing that B-doped TiO₂ could narrow the band gap of pure TiO₂. In the photocatalytic kinetics of the photodegradation, the BPA photodegradation rate constants were 1.67 and 1.08 h⁻¹, respectively. The BPA removal rate satisfies pseudo-first-order kinetics. Results showed that photocatalysts doped with boron displayed greater photodegradation (88% BPA removal) than pure TiO₂ (65% BPA removal)_. Experimental results indicated that B-doped TiO₂ not only was an effective photocatalyst, but also had considerable mineralization effects. The recycling test revealed that the photocatalyst remained effective after 10 uses, revealing the stability and reusability.