Mechanochemical Synthesis of Bi2VO5.5 for Improved Photocatalytic Dye Degradation

A single-phase Bi₂VO_5.5 powder is formed effectively through a mechanochemical ball milling approach at 650 °C in 5 h and its photocatalytic performance on methylene blue dye is explored. X-ray diffraction and Raman spectroscopy analytical instruments are utilized to confirm the phase formation. The evident presence of irregular-shaped grains is affirmed using a scanning electron microscope. To ascertain the chemical condition of the components present, the Bi₂VO_5.5 powdered sample undergo an X-Ray photoelectron spectroscopy investigation. The sample is analyzed using a time-dependent photocurrent to discern its charge carrier transportation behavior. A photocatalytic study using Bi₂VO_5.5 powder produced through the mechanochemical ball milling method has not been explored till now. The efficacy of the ball-milled Bi₂VO_5.5 powder to attain enhanced photocatalytic efficiency which hasn't been investigated till now, is explored. The ball-milled Bi₂VO_5.5 sample achieved 70% degradation efficiency when performing the photocatalysis investigation. The photocatalytic dye degradation discerns pseudo-first-order kinetics and achieves a notable k value of 0.00636 min^-1. The scavenger test indicates that h⁺ radicals are the prominent active species during the photocatalysis experiment. The germination index is determined by conducting a phytotoxicity test with the use of Vigna radiata seeds. Here ball-milled Bi₂VO_5.5 powder attains enhanced dye degradation efficiency.

Controlled synthesis of Bi2O2CO3 nanorods with enhanced photocatalytic performance

Bi₂O₂CO₃ nanorod is synthesized via solid–gas high temperature method and exhibits excellent photocatalytic activity for degrading salicylic acid.

BiOBr/Ti3C2 nanocomposites prepared via an octanol solvothermal method to achieve enhanced visible photocatalytic properties

BiOBr nanospheres grown in situ on lamellar Ti₃C₂ were synthesised in an octanol solvothermal system to obtain BiOBr/Ti₃C₂ heterojunction composites with high visible photocatalytic activity (OBT).

Unique 1D/2D Bi2O2CO3 nanorod-Bi2WO6 nanosheet heterostructure: synthesis and photocatalytic performance

A novel 1D/2D Bi2O2CO3–Bi2WO6 heterostructure was synthesized by high temperature calcination. These 1D/2D Bi2O2CO3–Bi2WO6 heterostructures displayed an outstanding photocatalytic activity to degrade organic compounds.

Green and controllable synthesis of one-dimensional Bi2O3/BiOI heterojunction for highly efficient visible-light-driven photocatalytic reduction of Cr(VI)

BiOI nanosheets have been successfully deposited on the porous Bi₂O₃ nanorobs via a one-pot precipitation method. The physicochemical features of the as-prepared materials were characterized in detail by a series of techniques, and the results revealed that BiOI nanosheets were evenly distributed on the porous Bi₂O₃ nanorobs. Because of higher photogenerated electron-hole pairs separation efficiency and the larger specific surface area compared to the pristine Bi₂O₃ and BiOI, the 50%Bi₂O₃/BiOI composite exhibited significantly enhanced photocatalytic activity for Cr(VI) reduction under visible light irradiation, and the reduction rate constant was 0.02002 min^-1, which was about 27.4 and 2.6 times higher than that of pure Bi₂O₃ (0.00073 min^-1) and BiOI (0.00769 min^-1), respectively. Moreover, the 50%Bi₂O₃/BiOI composite also possessed the excellent photochemical stability and recyclability, thereby facilitating its wastewater treatment application.

Innovative multifunctional hybrid photoelectrode design based on a ternary heterojunction with super-enhanced efficiency for artificial photosynthesis

Electrochemical cells for direct conversion of solar energy to electricity (or hydrogen) are one of the most sustainable solutions to meet the increasing worldwide energy demands. In this report, a novel and highly-efficient ternary heterojunction-structured Bi₄O₇/Bi_3.33(VO₄)₂O₂/Bi₄₆V₈O₈₉ photoelectrode is presented. It is demonstrated that the combination of an inversion layer, induced by holes (or electrons) at the interface of the semiconducting Bi_3.33(VO₄)₂O₂ and Bi₄₆V₈O₈₉ components, and the rectifying contact between the Bi₄O₇ and Bi_3.33(VO₄)₂O₂ phases acting afterward as a conventional p-n junction, creates an adjustable virtual p-n-p or n-p-n junction due to self-polarization in the ion-conducting Bi₄₆V₈O₈₉ constituent. This design approach led to anodic and cathodic photocurrent densities of + 38.41 mA cm^-2 (+ 0.76 V_RHE) and- 2.48 mA cm^-2 (0 V_RHE), respectively. Accordingly, first, this heterojunction can be used either as photoanode or as photocathode with great performance for artificial photosynthesis, noting, second, that the anodic response reveals exceptionally high: more than 300% superior to excellent values previously reported in the literature.

Photocatalytic degradation of sulfamethazine using a direct Z-Scheme AgI/Bi4V2O11 photocatalyst: Mineralization activity, degradation pathways and promoted charge separation mechanism

Z-scheme heterojunction can not only promote the separation of photogenerated carriers, but also retain the strong redox potential of the system, which would greatly improve the photocatalytic performance of catalyst. Herein, a Z-scheme AgI/Bi₄V₂O₁₁ heterojunction photocatalyst was prepared by a hydrothermal process combined with in situ coprecipitation process. Multiple techniques were employed to investigate the morphology, composition, chemical and electronic properties of the as-prepared samples. The obtained Z-scheme AgI/Bi₄V₂O₁₁ heterojunction photocatalyst exhibited remarkably enhanced photocatalytic performance towards sulfamethazine (SMZ) degradation under visible light irradiation. Especially, the 20 wt% AgI/Bi₄V₂O₁₁ composites exhibited the highest photocatalytic activity for sulfamethazine (SMZ) degradation and 91.47% SMZ would be eliminated within 60 min. In comparison with NO₃^- and SO₄^2-, the presence of Cl^- and HCO₃^- presented more obviously inhibition effects on SMZ degradation. The possible degradation pathways of SMZ were speculated by identifying degradation intermediates. O₂^-, h⁺ and OH all involved in the photocatalytic degradation SMZ. The highly enhanced photocatalytic performance might be attributed to form Z-scheme junction between AgI and BVO, which are conducive to the efficient charges separation and maintain high redox potential. This work enriches Bi₄V₂O₁₁-based Z-scheme heterojunction photocatalytic system and provides a reference for the preparation of effective Z-scheme junction photocatalysts.

Synthesis of a novel one-dimensional Bi2O2CO3–BiOCl heterostructure and its enhanced photocatalytic activity

A novel one-dimensional Bi₂O₂CO₃–BiOCl heterostructure was synthesized. BiOCl nanosheets uniformly and vertically grew onto the Bi₂O₂CO₃ porous rods via crystallographic oriented epitaxial nucleation and growth. Bi₂O₂CO₃–BiOCl displayed excellent photocatalytic activity.