Ag‐Doped TiO 2 Nanoparticles as an Effective Photocatalyst for Degradation of Indigo Carmine Dye under Visible Light

Hydrothermal synthesis and structural optimization of Bi2O3/Bi2WO6 nanocomposites for synergistic photodegradation of Indigo Carmine dye

Future research directions aim to optimize the efficiency and sustainability of bismuth-based semiconductors for environmental remediation. In this study, potent Bi2O3/Bi2WO6 composites were synthesized via a facile in situ hydrothermal-assisted impregnation of Bi3+ onto WO3 nano-substrate. Comprehensive characterization using HR-TEM, SEM-EDX, PXRD, XPS, FTIR, PL, and DRS confirmed the structural, morphological, and optical properties of the synthesized materials. The optimized Bi2O3/Bi2WO6 heterojunction exhibited significantly enhanced photocatalytic activity under visible-light (λ > 350 nm) compared to pristine Bi2O3 and WO3, effectively degrading Indigo Carmine (IC) dye. The UV-Vis spectroscopy and chemical oxygen demand (COD) analyses validated the degradation efficiency. A detailed photocatalytic mechanism was proposed based on trapping experiments, band position calculations, and photoluminescence measurements. Furthermore, the fabricated nanocomposites demonstrated excellent stability and recyclability, highlighting their potential for environmental remediation. This study provides a promising strategy for designing efficient visible-light-driven photocatalysts for wastewater treatment.

Visible light assisted photocatalytic degradation of mixture of reactive ternary dye solution by Zn-Fe co-doped TiO2 nanoparticles

The current study deals with the synthesis of novel Zn, and Fe co-doped TiO2 photocatalyst by the sol-gel method at room temperature. The prepared photocatalysts are characterized by several standard analytical tools. X-ray diffraction (XRD) and Raman analysis verifies the tetragonal anatase phase of TiO2 in all synthesized nanoparticles. The morphology and chemical composition of ZFT_2.5 were confirmed using the Field-Emission Scanning Electron Microscope (FE-SEM) and energy dispersive X-ray (EDAX) analysis respectively. X-ray photoelectron spectroscopy (XPS) measurements verify the binding energies of a host and dopant material. The High resolution transmission electron microscopy (HR-TEM) reveals the presence of spherical nanoparticles in ZFT_2.5 photocatalyst with a diameter ranging from 8 to 20 nm. The absorption spectra of the prepared nanoparticles exhibit strong absorption in visible light. The synergistic effect created by Zn and Fe blocked the light induced charge carriers and delayed the recombination probability. The photocatalyst ZFT_2.5 was tested for photocatalytic degradation against the mixture of the three cationic dyes [rhodamine B (RhB), malachite green (MG), and methylene blue (MB)] under exposure of visible light. Total organic carbon (TOC) study was performed to evaluate the organic character of the photodegradate dye solution.

Visible light assisted surface plasmon resonance triggered Ag/ZnO nanocomposites: synthesis and performance towards degradation of indigo carmine dye

Water pollution caused by organic compounds, generated from different industries, has gained attention worldwide today. In this regard, significant efforts have been made for a suitable dye degradation technology. Zinc oxide (ZnO)-based photocatalysts are considered novel materials to degrade organic effluents in contaminated water. The facile synthesis of Ag/ZnO nanocomposites and its application for the enhanced degradation of indigo carmine (IC) dye under visible light irradiation is reported in this paper. The prepared photocatalysts were characterized using various analytical techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron (XPS) spectroscopy, FTIR, Raman, impedance study, UV-Vis, and photoluminescence (PL). Prepared Ag/ZnO nanocomposites were tested for degradation of IC dye in visible light. The degradation efficiency of IC dye was found to be 95.71% in 120 min, with a rate constant of 0.02021 min-1. This improved photocatalytic activity of Ag/ZnO nanocomposites was mainly due to the absorption of visible light caused by surface plasmon resonance (SPR) derived from Ag nanoparticles (NPs) and electron-hole separation. Radical trapping experiments suggest that holes (h+) and superoxide radical (O2•-) are the key factors in photocatalytic IC dye degradation.