Simple and scalable synthesis of urchin-like ZnO nanoparticles via a microwave-assisted drying process

A new and simple method was applied for the synthesis of ZnO nanoparticles with an average size of 20 nm. In this microwave-assisted combustion method, glycine as a fuel and zinc nitrate as precursor were used. The final product was obtained very fast with high yield and purity. The synthesized nanoscale ZnO was characterized by X-ray Diffraction (XRD), Energy Dispersive X-ray spectroscopy (EDX), and Fourier transform infrared spectroscopy (FT-IR). The size and morphology of the ZnO nanoparticles have been determined by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) techniques. This is a simple and fast method for the preparation of ZnO nanoparticles with no need for expensive materials or complicated treatments.

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Microwave-assisted synthesis, characterization and antibacterial activity of Ag/ZnO nanoparticles supported bentonite clay

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2013.08.074 ◽

2013 ◽

Vol 262 ◽

pp. 439-446 ◽

Cited By ~ 99

Author(s):

Sarah C. Motshekga ◽

Suprakas S. Ray ◽

Maurice S. Onyango ◽

Maggie N.B. Momba

Keyword(s):

Antibacterial Activity ◽

Zno Nanoparticles ◽

Bentonite Clay ◽

Microwave Assisted Synthesis ◽

Microwave Assisted

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Assessment of Magnetic Properties between Fe and Ni Doped ZnO Nanoparticles Synthesized by Microwave Assisted Synthesis Method

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.317.119 ◽

2021 ◽

Vol 317 ◽

pp. 119-124

Author(s):

Sabiu Said Abdullahi ◽

Garba Shehu Musa Galadanci ◽

Norlaily Mohd Saiden ◽

Josephine Ying Chyi Liew

Keyword(s):

Magnetic Properties ◽

Zno Nanoparticles ◽

Room Temperature ◽

Synthesis Method ◽

Dilute Magnetic Semiconductors ◽

High Coercivity ◽

Microwave Assisted Synthesis ◽

Ferromagnetic Behavior ◽

Microwave Assisted ◽

Doped Zno

The emergence of Dilute Magnetic Semiconductors (DMS) with a potentials for spintronic application have attracted much researches attention, special consideration has been given to ZnO semiconductor material due to its wide band gap of 3.37 eV, large exciting binding energy of 60 meV, moreover, its ferromagnetic behavior at room temperature when doped with transition metals. MxZn1-xO (M = Fe or Ni) nanoparticles were synthesized by microwave assisted synthesis method calcined at 600°C. The structural, morphological and magnetic properties of these nanoparticles were studied using X-ray Diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Vibrating Sample Magnetometer (VSM) respectively. Single phase Wurtzite hexagonal crystal structure was observed for the undoped and Fe doped ZnO nanoparticles with no any impurity, whereas Ni doped ZnO nanoparticles shows the formation of NiO impurities. The magnetic measurement reveals a diamagnetic behavior for the undoped ZnO meanwhile a clear room temperature ferromagnetism was observed for both Fe and Ni doped ZnO. Fe doped ZnO present a high saturation magnetization compared to Ni doped ZnO. However, Ni doped ZnO present high coercivity. The research was confirmed that Fe doped ZnO material will be good material combination for spintronic applications.

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A facile microwave-assisted synthesis of ZnO nanoparticles and their photocatalytic activity: Effect of pH

BISTUA REVISTA DE LA FACULTAD DE CIENCIAS BASICAS ◽

10.24054/01204211.v2.n2.2020.821 ◽

2021 ◽

Vol 18 (2) ◽

pp. 3-8

Author(s):

Aura S. Merlano ◽

Ángel Salazar

Keyword(s):

Photocatalytic Activity ◽

Zno Nanoparticles ◽

Microwave Assisted Synthesis ◽

Nano Zno ◽

Effect Of Ph ◽

Microwave Assisted ◽

Activity Effect ◽

Uv Visible

Este estudio reporta una síntesis fácil, libre de surfactantes y asistida por microondas para la producción de nanopartículas de óxido de zinc (ZnO). Se investigó el efecto del valor del pH sobre las propiedades químicas, ópticas, morfológicas y fotocatalíticas de las nanopartículas de ZnO. Las nanopartículas se caracterizaron mediante microscopía electrónica de barrido (SEM), espectroscopía infrarroja por transformada de Fourier (FTIR), espectroscopía de rayos X por dispersión de energía (EDS) y espectroscopía UV-visible (UV-Vis). El análisis SEM muestra que el tamaño de las partículas disminuye con el aumento del valor de pH. Los espectros UV-Vis muestran picos de absorción excitónica alrededor de 334-359 nm. Se encontró que la brecha de energía de las muestras disminuye con el aumento del valor de pH. Finalmente, se evaluó la eficiencia fotocatalítica de los nanomateriales de ZnO mediante la degradación de naranja de metileno (MO) bajo irradiación de luz UV-A y se logró una eficiencia de degradación del colorante del 93.04% para la muestra de ZnO con pH-13. Los resultados experimentales confirman que la ruta propuesta para producir ZnO es fácil, reproducible y amigable con el medio ambiente. Además, el nano ZnO tiene un gran potencial como fotocatalizador para eliminar compuestos orgánicos.

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Freeze versus Spray Drying for Dry Wild Thyme (Thymus serpyllum L.) Extract Formulations: The Impact of Gelatin as a Coating Material

10.20944/preprints202105.0358.v1 ◽

2021 ◽

Author(s):

Aleksandra A. Jovanović ◽

Steva M. Lević ◽

Vladimir B. Pavlovic ◽

Smilja B. Markovic ◽

Rada V. Pjanovic ◽

...

Keyword(s):

Spray Drying ◽

Dry Weight ◽

Drying Process ◽

Scanning Calorimetry ◽

Coating Agent ◽

Microwave Assisted ◽

Freeze Dried ◽

Wild Thyme ◽

The Impact ◽

Spray Dried

Freeze drying was compared with spray drying regarding feasibility to process wild thyme drug in order to obtain dry formulations at laboratory scale starting from liquid extracts produced by different extraction methods: maceration, heat-, ultrasound-, and microwave-assisted extractions. Higher powder yield (based on the dry weight prior to extraction) was achieved by freeze than spray drying and lower loss of total polyphenol content (TPC) and total flavonoid content (TFC) due to the drying process. Gelatin as a coating agent (5% w/w) provided better TPC recovery by 70% in case of lyophilization and higher powder yield in case of spray drying by diminishing material deposition on the wall of the drying chamber. The resulting gelatin-free and gelatin-containing powders carried polyphenols in amount ~190 and 53-75 mg gallic acid equivalents GAE/g of powder, respectively. Microwave-assisted extract formulation distinguished from others by higher content of polyphenols, proteins and sugars, higher bulk density and lower solubility. The type of the drying process affected mainly position of the gelatin-derived -OH and amide bands in FTIR spectra. Spray dried formulations compared to freeze dried expressed higher thermal stability as confirmed by differential scanning calorimetry analysis and higher diffusion coefficient; the last feature can be associated with the lower specific surface area of irregularly shaped freeze-dried particles (151-223 µm) compared to small microspheres (~8 µm) in spray-dried powder.

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