Effects of morphology, surface area, and defect content on the photocatalytic dye degradation performance of ZnO nanostructures

RSC Advances ◽  
2014 ◽  
Vol 4 (77) ◽  
pp. 41099-41110 ◽  
Author(s):  
Natalia Morales Flores ◽  
Umapada Pal ◽  
Reina Galeazzi ◽  
Alberto Sandoval

Contributions of morphology, surface area, and defect content, on the photocatalytic activity of ZnO nanostructures have been discussed.

2021 ◽  
Author(s):  
Harsha Bantawal ◽  
Sandhya U. Shenoy ◽  
Denthaje Krishna Bhat

CaTiO3 has attracted enormous interest in the field of photocatalytic dye degradation and water splitting owing to its low cost, excellent physicochemical stability and structural tunability. Herein, we have developed...


2017 ◽  
Vol 19 (2) ◽  
pp. 56-60 ◽  
Author(s):  
Loghman Karimi

Abstract This study presents a facile approach for the preparation of MoS2 nanosheet decorated by porous titanium dioxide with effective photocatalytic activity. Mesoporous titanium dioxide nanostructures first synthesized by a hydrothermal process using titanium (III) chloride and then the MoS2/TiO2 were prepared through mixing of MoS2 nanosheet with mesoporous titanium dioxide under ultrasonic irradiation. The synthesized nanocomposite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), and Brunauer-Emmett-Teller (BET) analysis. The results showed that the nanocomposite has mesoporous structure with specific surface area of 176.4 m2/g and pore diameter of 20 nm. The as-prepared MoS2/TiO2 nanocomposites exhibited outstanding photocatalytic activity for dye degradation under sunlight irradiation, which could be attributed to synergistic effect between the molybdenum disulfide nanosheet and mesoporous titanium dioxide. The photocatalytic performance achieved is about 2.2 times higher than that of mesoporous TiO2 alone. It is believed that the extended light absorption ability and the large specific surface area of the 2D MoS2 nanosheets in the nanocomposite, leading to the enhanced photocatalytic degradation activity.


2018 ◽  
Vol 779 ◽  
pp. 97-101 ◽  
Author(s):  
Shynggys Sadyk ◽  
Timur Sh. Atabaev

In this study, a facile method was used to prepare ZnO tetrapods for potential dye degradation applications. Field emission scanning electron microscope (FESEM), energy-dispersive X-ray spectroscopy (EDX) and UV-Vis spectroscopy were employed to investigate the morphology, chemical composition, and photocatalytic properties of prepared ZnO tetrapods. A Rhodamine B (RB) dye was used as a model dye to study the photocatalytic activity of the prepared sample. It was shown that RB dye can be efficiently degraded in the presence of ZnO tetrapods under continuous UV-light illumination. Thus, prepared ZnO tetrapods with excellent photocatalytic properties can be potentially used in wastewater treatment.


2018 ◽  
Vol 5 (9) ◽  
pp. 2257-2267 ◽  
Author(s):  
Shuhua Liang ◽  
Xufeng Gou ◽  
Jie Cui ◽  
Yongguang Luo ◽  
Hongtao Qu ◽  
...  

Surface heterojunctions were constructed in ZnO mesocrystals with co-exposed curved (101̄1) and flat (0001̄) surfaces and greater photocatalytic dye degradation was achieved compared to that of ZnO nanocrystals.


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mahwash Mahar Gul ◽  
Khuram Shahzad Ahmad

Abstract Photocatalysis by utilizing semiconductors for the removal of toxic pollutants has gained tremendous interest for remediation purposes. The organic pollutants usually include; pesticides, dyes and other phenolic compounds. An imperative restraint associated with the photocatalytic effectiveness of the catalyst is the rapid recombination of the light generated electrons and holes. The particle agglomeration and electron-hole recombination hinders the rate of pollutant removal. For decades, researchers have used metal-sulfides efficiently for photocatalytic dye degradation. The recent use of hybrid nanomaterials with the combination of graphene derivatives such as graphene oxide and reduced graphene oxide (GO/rGO)-metal sulfide has gained interest. These composites have displayed an impressive upsurge in the photocatalytic activity of materials. The current review describes the various researches on dye photodegradation by employing (GO/rGO)-metal sulfide, exhibiting a boosted potential for photocatalytic dye degradation. A comprehensive study on (CuS, ZnS and CdS)–GO/rGO hybrid composites have been discussed in detail for effective photocatalytic dye degradation in this review. Astonishingly improved dye degradation rates were observed in all these studies employing such hybrid composites. The several studies described in the review highlighted the varying degradation rates based on diverse research parameters and efficacy of graphene derivatives for enhancement of photocatalytic activity.


NANO ◽  
2021 ◽  
pp. 2150034
Author(s):  
Mingwei Liu ◽  
Linhua Jiang ◽  
Mingxia Shen ◽  
Mingzhi Guo ◽  
Pengfei Zhu ◽  
...  

The manufacture of diatomite-supported composite catalyst with enhanced photocatalytic activity is of great interest for wastewater treatment. In this study, the pretreated diatomite (PD) with 5[Formula: see text]wt.% NaOH solution possessed better pore structure and large specific surface area. A facile hydrothermal-photoreduction method was adopted to prepare Bi/BiVO4/PD composite. The chemical composition, microstructure morphology and pore structure of samples were investigated by means of XRF, XRD, SEM, TEM, EDS, XPS and BET methods. The results showed that the metallic Bi was uniformly deposited on the BiVO4. After loaded on PD, both surface area and total pore volume had a significant increase. In addition, UV-vis diffuse reflectance spectra presented that the absorption capacity of Bi/BiVO4/PD-25% composite in the visible light range was remarkably high due to the surface plasmon resonance (SPR) caused by metallic Bi. From photoluminescence (PL) spectra and transient photocurrents, the heterojunction formed between Bi/BiVO4 and PD helped promoting the separation and migration of photo-generated carriers, which in turn led to higher photocatalytic activity. Compared with Bi/BiVO4, Bi/BiVO4/PD loaded with 25[Formula: see text]wt.% PD showed highest decolorization rate for rhodamine B (RhB), malachite green (MG), methylene blue (MB), methyl orange (MO) and lemon yellow (LY) under visible light irradiation. According to trapping experiments on free radicals, the active species that played a decisive role in RhB degradation were h[Formula: see text] and [Formula: see text]. Findings from this study suggest that Bi/BiVO4/PD-25% composite holds great promise for dye degradation and wastewater treatment.


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