Synthesis of ZnO photocatalyst via ZnO2 precursor and its application for dye degradation from effluent under solar irradiation

Chaskar

et al. 2017

Preprint

Self Cite

Abstract. In a search of low cost photocatalyst for dye degradation we have evaluated photocatalytic activity of the Analytical Reagent (AR) grade ZnO, TiO2 and SnO2. The photocatalytic activity was evaluated towards the decolourization of structurally diverse dyes such as crystal violet, basic blue and methyl red under solar irradiation and compared with benchmark Degussa P-25 (TiO2) photocatalyst. The received metal oxides were characterized by the different physicochemical methods of analysis. Powder XRD analysis showed that these metal oxides are polycrystalline in nature and crystallized in different crystalline phases. The crystalline phases of these oxides were found to be hexagonal for ZnO, tetragonal for TiO2 and rutile for SnO2. Particle morphology was analysed through SEM imaging and it showed that these oxides consists of different particle morphologies and have different particle sizes. Band gap was evaluated from diffuse reflectance spectra and it was found to be 3.24, 3.20 and 3.66 eV respectively for ZnO, TiO2 and SnO2. Among the three AR grade oxides, ZnO exhibited highest photocatalytic activity which is even higher than Degussa P-25 (TiO2) photocatalyst. About 20&#8201;% enhancement in the photocatalytic activity of AR grade ZnO was observed when silver metal loaded of on ZnO surface.

Section: Characterisation Of Catalystssupporting

confidence: 93%

“…Many attempts have been made to study photocatalytic activity of different semiconductors such as SnO2, ZrO2, CdS and ZnO (Sakthivel et. al., 2003;Pawar et. al., 2016;Cheng et.…”

Section: Introductionmentioning

confidence: 99%

Photocatalytic degradation of Dyes in Water by Analytical Reagent Grade Photocatalysts – A comparative study

Chaskar

et al. 2017

Preprint

Self Cite

“…Lattice parameters were calculated for all three metal oxides by using XRD data and are listed in Table 1. The lattice parameters were consistent with reported values (Pawar et al, 2016;Cheng et al, 2011;Li et al, 2014Li et al, , 2013. Crystallite sizes were calculated using the intense peaks in XRD by the Debay-Sherrer formula; they were 103, 36, and 66 nm for ZnO, TiO 2 , and SnO 2 , respectively.…”

Section: Characterisation Of Catalystssupporting

confidence: 85%

“…where k obs is the apparent reaction rate constant, A 0 is the initial absorbance of the dye solution, and A is the absorbance of the dye solution after irradiation at time t. Finally, we have determined a decrease in the chemical oxygen demand (COD) of a treated dye solution according to the previously described method (Pawar et al, 2016).…”

Section: Photoreactor and Degradation Experimentsmentioning

confidence: 99%

Photocatalytic degradation of dyes in water by analytical reagent grades ZnO, TiO2 and SnO2: a comparative study

Chaskar

et al. 2017

Drink. Water Eng. Sci.

Self Cite

Abstract. In this study, we evaluated the photocatalytic activities of analytical reagent (AR) grade ZnO, TiO2, and SnO2 to identify a low-cost photocatalyst for dye degradation. The obtained samples of ZnO, TiO2, and SnO2 were characterised by X-ray diffractogram (XRD), scanning electron microscope imaging, and UV-VIS diffuse reflectance spectroscopy. The decolourisation of three structurally diverse dyes, namely crystal violet, basic blue, and methyl red under solar irradiation, was used to evaluate the photocatalytic activities of three metal oxides. The photocatalytic activities of the received three metal oxides were tested with the photocatalytic degradation of dyes and compared with Degussa P-25. Dye solutions with each metal oxide at initial pH 9 were subjected to irradiation under sunlight and monitored for up to the stage of complete decolourisation. The results indicate that ZnO exhibited the highest photocatalytic activity as compared to TiO2 and SnO2 as well as that of Degussa P-25 (TiO2). The photocatalytic dye decolourisation rates with ZnO were 1.14–1.35, 1.70–3.1, and 4–8.5 times higher than those of the Degussa P-25, TiO2, and SnO2, respectively. The percentage COD removal was studied for ZnO and partial removal was observed at the decolourisation stage. To enhance photocatalytic activity of AR grade ZnO, it was loaded with Ag metal and about 20 % enhancement in the activity was observed.

“…ZnO was synthesized, using a known method, from zinc oxalate as a precursor [38,39]. The precursor was synthesized by dry grinding zinc acetate and oxalic acid in 1:1 proportion.…”

Section: Synthesis Of Zno Nanoparticlesmentioning

confidence: 99%

Experimental and theoretical study of 1, 4-naphthoquinone based dye in dye-sensitized solar cells using ZnO photoanode

Materials Science-Poland

Pathan

et al. 2017

A dye-sensitized solar cell (DSSC) was assembled using a dye 4-(3-chloro-1, 4-dioxo-1, 4-dihydronaphthalen-2-ylamino) benzoic acid with ZnO as a photoanode. It was synthesized using 2, 3-dichloro 1, 4-naphthoquinone and p-amino benzoic acid. The spectral features of the dye were analyzed in ethanol using experimental and computational methods. The theoretical investigations revealed that the synthesized dye may act as a sensitizer in DSSCs. The photoelectrochemical performance was tested under direct sunlight using a sandwich type DSSC. The photovoltaic data of the dye adsorbed on ZnO films indicated thepower conversion efficiency of 1.07 % under sunlight with a light intensity of 39 mW·cm-2.