Hydrochloric acid and dopamine hydrochloride combined regulation of the photocatalytic activity of heterogeneous DBSO microflowers in visible light degradation of various dye water and antibiotics

Abstract

Heterostructures with intimate contact interfaces and well-matched band structure construction are considered to be one the effective methods to promote photogenerated carrier separation and photocatalytic semiconductor activity. Herein, a simple joint post-modification method of hydrochloric acid and dopamine hydrochloride mediated under acidic conditions was proposed. Bi12SiO20-Bi2O2SiO3-BiOCl curved microflower photocatalyst with double heterojunction and large specific surface area was prepared. Hydrochloric acid and dopamine hydrochloride act as reactants and halogen sources in the composite photocatalyst, and their amount precisely control the surface morphology and the thickness of nanosheets. Benefiting from the synergistic effect of morphology regulation and interface optimization, the DBSO-10 not only changes its morphology from the original bone rod structure to the curved microflower structure with a large specific surface area, but also formes a double type-II heterostructure with tight interface connection. And the new microflower photocatalyst can achieve a degradation rate of 99.7 % in 20 min, which is 40 times higher than that of Bi12SiO20-Bi2O2SiO3 photocatalyst. Notably, the material can also effectively degrade five catalysts including dyes and antibiotics within 1 h.