Improved photocatalytic activity of ZnO-TiO 2 nanocomposite catalysts by modulating TiO 2 thickness

In view of enhanced bioactivity and photocatalytic applications, the doped material has gained much attention and present study was focused on the preparation of Zn doped WO 3 (Zn-d-WO 3 ) via precipitation method. The prepared Zn-d-WO 3 was characterized by Scanning Electron Microscopy (SEM), x-ray diffraction (XRD), Energy-dispersive x-ray (EDX). The effect of Zn concentration was studied on antibacterial, antifungal and photocatalytic activities along with structural and morphological variation. The Zn-d-WO 3 was triclinic, spherical and rod shaped and particle size was decreased as the Zn concentration increased. The antimicrobial activity of Zn-d-WO 3 was evaluated against a panel of bacterial strains (Escherichia coli, Pasturellamu ltocida, Bacillus subtilis, Staphylococcus aureus) and fungal strain (Aspergillus niger, Aspergillus flavus, Penicillium notatum). The Zn-d-WO 3 showed promising antibacterial activity with minimum inhibitory concentration (MIC) values in the range of 211-387 (μg ml −1 ), whereas the antifungal activity was less than the standard (Fluconazole), which revealed that the Zn-d-WO 3 are highly active against bacterial strains since activity was comparable with standard drug (Rifampicin). The photocatalytic activity (PCA) was evaluated by degrading methylene blue (MB) dye in an aqueous solution and dye degradation of 78% and 92% was achieved in 120 min under visible and UV irradiation, respectively. Results revealed that the Zn-d-WO 3 could possibly be used as photocatalyst for the degradation of dyes in wastewater.

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of Zn doped WO₃ nanoparticles: photocatalytic, antifungal and antibacterial activities evaluation

Arshad¹,

Ehtisham-ul-Haque

Bilal

et al. 2020

“…For PCA evaluation, the catalyst and sample (10:90 ratio) (at spcific, pH, dye and H 2 O 2 concentration) were kept in dark for 20 min and then, irradiated for stipulated time periods to UV and sunlight radiations. The absorbance (λ max =617 nm) of dye sample was recorded before and after irradiation and dye degradation was estimated using relation shown in equation (2). Where, C o and C f are representing absorbance before and after treatment, respectively.…”

Section: Photocatalytic Activity Evaluationmentioning

confidence: 99%

“…Among pollutants, synthetic dyes are of major concern because of their high production and disposal rate and severe toxicity. Dyes bearing effluents from paper, textiles, plastics and rubber industry are discharged into water bodies without any treatment, which pollute the water bodies and is responsible for different diseases like cancer, respiratory illness and endocrine diseases [1][2][3][4][5]. Various methods i.e., chemical process, physical techniques and biological process have been used for the removal of dye from industrial effluents [6][7][8][9][10][11][12].…”

Section: Introductionmentioning

confidence: 99%

Synthesis of immobilized ZnO over polyurethane and photocatalytic activity evaluation for the degradation of azo dye under UV and solar light irardiation

Inderyas

Bhatti

Ashar

et al. 2020

Zinc oxide (ZnO) nanoparticles were immobilized on polyurethane foam (PUF) and employed for the degradation of Acid black 1 dye (AB1). The ZnO/PUF was characterized by x-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive x-ray (EDX) techniques. Process variables i.e., dye concentration, pH, concentration of H 2 O 2 , irradiation time were optimized for maximum degradation of dye. ZnO/PUF showed promising efficiency for the degradation of AB1 dye and up to 86% and 65% dye degradation was achieved under UV and solar light irradiation at neutral pH, 4% H 2 O 2 , 240 min/sunlight and 75 min/UV irradiation time using 40 mg l −1 dye initial concentration. The optimum conditions were applied for the treatment of textile wastewater and biological oxygen demand (BOD) and total organic carbon (TOC) were reduced up to 70% and 80%, respectively. In view of promising photocatalytic activity (PCA), ZnO/PUF could possibly be used for the treatment of wastewater contains dyes.

“…The removal of dyes from effluent is a difficult task due to their stable nature, which needs to be treated wastewater before being discharged in to water bodies. Different techniques are in practice to achieve the goal i.e., photocatalysis using nanoparticles and adsorption using adsorbents [7][8][9][10]. Acidic dyes are important class of versatile and chemically stable organic dyes and widely used for staining of wool and nylon [11].…”

Section: Introductionmentioning

confidence: 99%

“…ZVI offers various advantages over other catalysts i.e., non-toxic, environmentally friendly, cost effective, easy to handle, higher surface area and enhanced reactivity [22]. The dye removal using ZVI happened through reductive (equations (1), (2)), oxidative (equations (3), (4)) and and coagulation/sedimentation mechanisms (equations (5)- (7)) [23]. For reduction process, e − and H 2 are produced and reduced the targeted species.…”

Section: Introductionmentioning

confidence: 99%

Facile synthesis of zero valent iron and photocatalytic application for the degradation of dyes

Bhatti

Iram

Iqbal

et al. 2020

In the present investigation, Zero valent iron (ZVI) was synthesized using ferrous sulfate and borohydrate in the presence of EDTA and characterized by x-ray Diffraction (XRD), Energydispersive x-ray (EDX) and Scanning electron microscope (SEM) techniques. The prepared ZVI catalytic activity was evaluated by degrading Acid Red 1 (AR1) and Acid Green 25 (AG25) dyes. The process variables such as pH, initial dye concentration, ZVI dose, contact time, hydrogen peroxide (H 2 O 2 ) and temperature were optimized for maximum dye degradation. AG25 removal was 98% at pH 4, ZVI dose 0.2 g l −1 , initial dye concentration 50 mg l −1 , 90 min reaction time and 8 mM H 2 O 2 concentration, whereas pH 2, ZVI dose 0.1 g l −1 , 50 mg l −1 initial dye concentration, 8 mM H 2 O 2 and 90 min were found to be optimum for AR1 maximum degradation of 91.60%. Behnajady-Modirshahla-Ghanbery kinetic model and thermodynamic study revealed the spontaneity and endothermic nature of the process. Results revealed that ZVI has potential to degrade the dyes and could possibly be used for the degradation of dyes in wastewater.