scholarly journals Modified and systematic synthesis of zinc oxide-silica composite nanoparticles with optimum surface area as a proper H2 S sorbent

2017 ◽  
Vol 95 (8) ◽  
pp. 1632-1632 ◽  
Author(s):  
Faeze Tari ◽  
Marzieh Shekarriz ◽  
Saeed Zarrinpashne ◽  
Ahmad Ruzbehani
Keyword(s):  
Zinc Oxide ◽  
Surface Area ◽  
Composite Nanoparticles ◽  
Silica Composite ◽  
Systematic Synthesis

SYNTHESIS AND CHARACTERIZATION OF NEEM-BASED ZINC OXIDE PHOTOCATALYST

2021 ◽  
Vol 36 (1) ◽  
pp. 9-15
Author(s):  
I.N Gana ◽  
V.U Ohageria ◽  
U.G Akpan ◽  
I.J Ani
Keyword(s):  
Zinc Oxide ◽  
Green Synthesis ◽  
Surface Area ◽  
Leaf Extract ◽  
Zinc Acetate Dihydrate ◽  
Sol Gel ◽  
Sem Analysis ◽  
X Ray ◽  
Bet Analysis ◽  
Neem Leaf Extract

The use of chemicals for the synthesis of photocatalyts poses threat to the environment. In this study, an active photocatalyst, Dalbejiya Dongoyaro (Azadirachta indica)-based zinc oxide (ZnO) was biosynthesized from zinc acetate dihydrate using sol gel and precipitation methods. The synthesized samples were characterized using Fourier Transfer InfraRed (FTIR), X-Ray Diffractometry (XRD), Brunauer Emmet Teller (BET), Energy Dispersive X-ray Spectroscopy (EDS) and Scanning Electron Microscopy (SEM) characterization techniques. The XRD and SEM analysis of the green synthesized and non-green synthesized ZnO demonstrated the formation of hexagonal wurtzite crystalline structure and agglomerated morphology. EDX analysis demonstrated the existence of Zn and O as the major constituents of the as-synthesized nanoparticles with traces of carbon which could be attributed to the carbon tape of the sample holder. The BET analysis displayed that the surface area of the ZnO nanoparticles increased from 23.75 to 97.08 cm3/g after the green synthesis. Based on the surface area values, it can be derived that neem leaf extract enhanced the surface area of the green synthesized sample. Green synthesis is a promising route for the synthesis of photocatalyst nanoparticle which is environmentally friendly and sustainable method. Keywords: Zinc oxide, Neem leaf extract, Photocatalyt, Degradation, Bio-synthesis

Preparation and Antibacterial Performances of Electrocatalytic Zinc Oxide Nanoparticles with Diverse Morphologies

2021 ◽  
Vol 17 (9) ◽  
pp. 1824-1829
Author(s):  
Junlin Li ◽  
Xiangfei Li ◽  
Dong Liang ◽  
Xiaojuan Zhang ◽  
Qing Lin ◽  
...  
Keyword(s):  
Zinc Oxide ◽  
Surface Area ◽  
Zinc Oxide Nanoparticles ◽  
Average Particle Size ◽  
Three Dimensional ◽  
Diffusion Method ◽  
Oxide Nanoparticles ◽  
Average Particle ◽  
X Ray Diffraction ◽  
Zno Nps

This study exploits the potential of zinc oxide nanoparticles (ZnO-NPs) with diverse morphologies as catalysts and antibacterial agent. Spherical ZnO-NPs, rod-shaped ZnO-NPs and flower-shaped ZnO-NPs were prepared by microemulsion method, solvent heat method and hydrothermal method, respectively. The structural characterizations of samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. XRD results revealed the formation of spherical ZnO-NPs, rod-shaped ZnO-NPs and flower-shaped ZnO-NPs were all wurtzite crystal structure. SEM results showed that spherical ZnO-NPs had an average particle size of 30–40 nm, rod-shaped ZnO-NPs were about 500 nm long and 100 nm wide with obvious hexagonal crystals. Flower-shaped ZnO-NPs had a three-dimensional appearance with obvious petals. Results of electrochemical HER (Hydrogen evolution reaction) experiments revealed that spherical ZnO-NPs exhibited the highest electrocatalytic activity at the lowest potential voltage due to their largest specific surface area. The antibacterial property of ZnO-NPs samples were studied by the optical density method and disc diffusion method. All samples had antibacterial effects against E. coli. and flower-shaped ZnO-NPs showed the best antibacterial activity due to the largest surface area in comparison with spherical ZnO-NPs and rod-shaped ZnO-NPs, which promised the maximum Zn2+ release as bactericide mechanism that registered in the case of different ZnO-NPs morphologies.

scholarly journals The Role of ALD-ZnO Seed Layers in the Growth of ZnO Nanorods for Hydrogen Sensing

Micromachines ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 491 ◽  
Author(s):  
Yangming Lu ◽  
Chiafen Hsieh ◽  
Guanci Su
Keyword(s):  
Zinc Oxide ◽  
Surface Area ◽  
Gas Sensing ◽  
Zno Nanorods ◽  
Clean Energy ◽  
Hydrogen Sensor ◽  
Zno Films ◽  
Hydrogen Sensing ◽  
Highly Sensitive ◽  
Seed Layers

Hydrogen is one of the most important clean energy sources of the future. Because of its flammability, explosiveness, and flammability, it is important to develop a highly sensitive hydrogen sensor. Among many gas sensing materials, zinc oxide has excellent sensing properties and is therefore attracting attention. Effectively reducing the resistance of sensing materials and increasing the surface area of materials is an important issue to increase the sensitivity of gas sensing. Zinc oxide seed layers were prepared by atomic layer deposition (ALD) to facilitate the subsequent hydrothermal growth of ZnO nanorods. The nanorods are used as highly sensitive materials for sensing hydrogen due to their inherent properties as oxide semiconductors and their very high surface areas. The low resistance value of ALD-ZnO helps to transport electrons when sensing hydrogen gas and improves the sensitivity of hydrogen sensors. The large surface area of ZnO nanorods also provides lots of sites of gas adsorption which also increases the sensitivity of the hydrogen sensor. Our experimental results show that perfect crystallinity helped to reduce the electrical resistance of ALD-ZnO films. High areal nucleation density and sufficient inter-rod space were determining factors for efficient hydrogen sensing. The sensitivity increased with increasing hydrogen temperature, from 1.03 at 225 °C, to 1.32 at 380 °C after sensing 100 s in 10,000 ppm of hydrogen. We discuss in detail the properties of electrical conductivity, point defects, and crystal quality of ALD-ZnO films and their probable effects on the sensitivity of hydrogen sensing.

scholarly journals Enhanced Hydrophilic and Electrophilic Properties of Polyvinyl Chloride (PVC) Biofilm Carrier

Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1240
Author(s):  
Haifeng Cai ◽  
Yang Wang ◽  
Kai Wu ◽  
Weihong Guo
Keyword(s):  
Contact Angle ◽  
Zinc Oxide ◽  
Surface Area ◽  
Polyvinyl Chloride ◽  
Positive Charge ◽  
Sem Images ◽  
Biofilm Carrier ◽  
Surface Contact Angle ◽  
Bacterial Adsorption ◽  
Scanning Electron

Polyvinyl chloride (PVC) biofilm carrier is used as a carrier for bacterial adsorption in wastewater treatment. The hydrophilicity and electrophilicity of its surface play an important role in the adsorption of bacteria. The PVC biofilm carrier was prepared by extruder, and its surface properties were investigated. In order to improve the hydrophilicity and electrophilic properties of the PVC biofilm carrier, polyvinyl alcohol (PVA) and cationic polyacrylamide (cPAM) were incorporated into polyvinyl chloride (PVC) by blending. Besides, the surface area of the PVC biofilm carrier was increased by azodicarbonamide modified with 10% by weight of zinc oxide (mAC). The surface contact angle of PVC applied by PVA and cPAM at 5 wt %, 15 wt % was 81.6°, which was 18.0% lower than pure PVC. It shows the significant improvement of the hydrophilicity of PVC. The zeta potential of pure PVC was −9.59 mV, while the modified PVC was 14.6 mV, which proves that the surface charge of PVC changed from negative to positive. Positive charge is more conducive to the adsorption of bacteria. It is obvious from the scanning electron microscope (SEM) images that holes appeared on the surface of the PVC biofilm carrier after adding mAC, which indicates the increase of PVC surface area.

scholarly journals Dye-Sensitized Solar Cells Based on High Surface Area Nanocrystalline Zinc Oxide Spheres

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Pavuluri Srinivasu ◽  
Surya Prakash Singh ◽  
Ashraful Islam ◽  
Liyuan Han
Keyword(s):  
Zinc Oxide ◽  
Solar Cells ◽  
Surface Area ◽  
High Surface ◽  
High Surface Area ◽  
Dye Sensitized Solar Cells ◽  
Oxide Material ◽  
Dye Sensitized ◽  
Sensitized Solar Cells ◽  
Nanocrystalline Zinc Oxide

High surface area nanocrystalline zinc oxide material is fabricated using mesoporous nanostructured carbon as a sacrificial template through combustion process. The resulting material is characterized by XRD, N2 adsorption, HR-SEM, and HR-TEM. The nitrogen adsorption measurement indicates that the materials possess BET specific surface area ca. 30 m2/g. Electron microscopy images prove that the zinc oxide spheres possess particle size in the range of 0.12 μm–0.17 μm. The nanocrystalline zinc oxide spheres show 1.0% of energy conversion efficiency for dye-sensitized solar cells.

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