Synthesis of novel p-n heterojunction m-Bi2O4/BiOCl nanocomposite with excellent photocatalytic activity through ion-etching method

Abstract

A novel p-n heterostructure photocatalyst m-Bi2O4/BiOCl was successfully synthetized through a facile ion-etching method. Via adjusting the added volume of HCl solution, a series of different ratios of composite photocatalysts were obtained. The as-prepared samples of physical, chemical and optical characteristics were examined by X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectroscopy, selected-area electron diffraction, Fourier transform infrared absorption, Raman microscope, N2 adsorption-desorption, X-ray photoelectron spectroscopy and UV-vis spectrum technologies. The photocatalysts showed high degradation rate and complete mineralization ability for methyl orange and tetracycline solution under visible light. The reaction rate constant of m-Bi2O4/BiOCl for methyl orange was 52.28 times higher than that of BiOCl. The characterization presented a good stability of materials. Furthermore, the photocurrent response test certified that the heterostructure effectively accelerated the separation and migration of photo-generated carries. The scavenger experiments evidenced that hole (h + ) and superoxide radical (•O2 − ) were the primary active radicals. A possible photocatalytic mechanism was proposed. This work provided an alternative photocatalyst applied to water environmental remediation.

Enhanced photocatalytic H2-production activity of WO3/TiO2 step-scheme heterojunction by graphene modification

“…Heterojunction construction by integrating two semiconductors is a universal strategy owing to its effectiveness in spatially separating the photoexcited electron-hole pairs via appropriate band alignments between the semiconductors [1,26]. Recently, a new step-scheme heterojunction (S-scheme heterojunction) concept was proposed to explain the increased charge transfer rate observed at the interface of two photocatalysts with staggered band structures [27].…”

Hydrolysis Mechanism of Bismuth in Chlorine Salt System Calculated by Density Functional Method

“…12) By substituting equations (10) and (11) into equation 12, we could obtain: , which was a constant; Substituting the reaction formula (3) into the formula (9), we could obtain:…”

“…Bismuth is widely used in metallurgy, medicine, chemical industry, photo catalyst, semiconductor, superconductor, nuclear industry material, environmental pollution treatment, etc. [5][6][7][8][9][10][11] Among them, lanthanidephoto catalysts are generally divided into lanthanide-based photocatalysts and lanthanide composite photocatalysts. Methods to prepare them generally include hydrolysis method [12][13], glycol-solvent-thermal method [14][15], extraction method [16] and so on.…”

Preparation of BiOCl0.9I0.1/β-Bi2O3 composite for degradation of tetracycline hydrochloride under simulated sunlight

“…BiOX (X = Cl, Br, and I) is a semiconductor with an indirect bandgap, and the recombination probability of the photogenerated carriers is relatively low [19][20][21]23,24]. These inherent structural advantages determine the intensive employment of BiOX in photocatalytic application [25][26][27][28][29][30].…”