Zinc and boron co-doped nanotitania with enhanced photocatalytic degradation of Acid Red 6A under visible light irradiation

Ravi Kumar Mulpuri,Manga Raju Imandi,Venkata Divya Lakshmi Kapuganti,Siva Rao Tirukkovalluri,Shaik Abdul Alim

doi:10.1186/s42834-019-0031-6

Abstract

The present investigation summarizes the synthesis and characterization of zinc and boron co-doped TiO2 nano catalyst by sol gel method at relatively low temperature and explored the optimum reaction parameters for the degradation of Acid Red 6A (AR 6A) under visible light irradiation. The structural, morphological, surface properties of the synthesized photocatalysts were characterized by X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, Transmission Electron Microscopy, Brunauer-Emmett-Teller, UV-Vis-Diffuse Reflectance Spectroscopy, X-ray Photo Electron Spectroscopy and Fourier Transform-Infra Red Spectroscopy. The findings of the characterization results revealed that Zn2+ ion was substitutionally doped into TiO2 lattice by replacing Ti4+ ion and a part of the boron substituted the oxygen in TiO2 lattice and the remaining amount was converted to B2O3 due to calcinations at 450 °C. The degradation of AR 6A was achieved at optimum reaction parameters, such as pH = 6 with a catalyst dosage 100 mg L−1 for the degradation of 5 mg L−1 of dye solution.

Highlights

For the degradation of a wide range of organic dye contaminants from textile and food industry, advanced oxidation process using semiconductors was considered as one of the most promising methods
There are no characteristic peaks observed for zinc oxides in X-Ray Diffraction (XRD) spectrum in all the co-doped samples, which implies that Zn2+ ions are incorporated into the lattice of TiO2 by substituting Ti4+ ion [13], whereas B3+ ion cannot substitute Ti4+ ion in the TiO2 lattice due to large ionic radii difference between Ti4+ (61 pm) and B3+ (23 pm) ions
To determine the effect of dopant concentrations of co-doped and undoped TiO2, experiments for codoped nanocatalysts containing various dopant concentrations were carried out for the photocatalytic degradation of Acid Red 6A (AR 6A) with the results presented in Fig. 8a and b and the experimental data presented in the Table 4

Summary

Introduction

For the degradation of a wide range of organic dye contaminants from textile and food industry, advanced oxidation process using semiconductors was considered as one of the most promising methods. Others [10, 11] attempted metal and non-metal (Cu & S, Fe & B) codoping into TiO2 lattice which resulted in the improved photocatalytic activity by minimizing the band gap, decreasing particle size, increasing the surface area and improved the trapping-to-recombination rate [12].

Results

Conclusion