Effect of Fe doping on the structural, optical and magnetic properties of combustion synthesized nanocrystalline ZnO particles

ZnO nanoparticles as efficient sunlight driven photocatalyst prepared by solution combustion method involved lime juice as biofuel

We have prepared high purity Zinc oxide (ZnO) nanoparticles (NPs) by solution combustion synthesis (SCS) method with the aid of lime juice extract. From powder X-ray diffraction (XRD) spectra, it is observed that the ZnO NPs possess single phase, hexagonal wurzite structure with sharp intense peak at (101) plane, agrees with the planes of SAED pattern. Further, the crystallite size is found to be around 18 nm. UV-Vis analysis shows strong UV absorbance band at 381 nm and PL measurements reveals the presence of strong UV emission at 347 nm along with few weak visible emissions. Optical studies infer the existence of lower recombination rate of electron-hole pair, influence the photocatalytic activity of ZnO. From XPS measurements, presence of oxygen rich states on surface are also confirmed (O 1 s states). The degradation performance and reusability of four different dyes (methylene blue (MB), methyl orange (MO), rhodamine B (RhB), Pararosaniline (PRA)) under UV and sunlight irradiations are carried out to illustrate the photo-catalytic activity in presence of a catalyst like ZnO NPs. Comparatively, about 98.8% of PRA and MB dyes are photodegraded at 90 and 75 min of sunlight irradiation, respectively. Among these two, PRA dye shows maximum degradation performance with shorter irradiation time along with good stability, which can be extend very well to minimize the pollution issues happening in society especially, industrial wastes.

Detection of SalmonellaTyphimurium in water and meat using nanosensor

The sensor dimensions are chosen (10 * 10 mm) and manufactured by the laser engraving system as a dimension of the fine copper die and installed on the glass substrate coated with the nano material and the mould is coated with silver by thermal vacuum evaporation and the fixation of the connecting electrodes. The surface properties and the structural, optical and electrical properties of the thin films were studied. Samples prepared with an X-ray diffraction device (XRD) were examined to ensure the presence of elements or compounds entering the coating layer, and an examination with an atomic force microscope (AFM) to identify the crystal size of the coating compound and a scanning electron microscope. Field (SEM) is to prove the existence and proportions of active ingredients. The UV nano composite spectra were studied to investigate the optical behavior of ZnO-rGO membranes (transmittance and absorption). The sensing properties were determined by measuring changes in the conductivity of the prepared bacteria present in water and flesh using current and voltage measurement I-V by two mass device methods and the results were accurate. The results proved that ZnO-rGO has high sensitivity towards bacteria and is made of thin films of nano composites and has a high performance to detect bacteria in water and meat. The goal of this study is to design and manufacture a nano sensor with high efficiency to detect a type of bacteria that the thin films deposited in the vacuum have properties excellent for accurate detection. The microbial detection devices based on thin materials are inexpensive and do not require trainers to use them, and they operate at room temperature. Thus they have the advantage of remote positioning and monitoring in dangerous places.

Optical and Electronic Analysis of Pure and Fe-Doped ZnO Thin Films Using Spectroscopic Ellipsometry and Kramers–Kronig Method

In the present work, pure and Fe-doped ZnO thin films were deposited on glass substrates by sol–gel method. Zinc acetate and iron nitrate were used as the starting material and dopant source, respectively. The concentration of Fe doping was 6[Formula: see text]at.% and 8[Formula: see text]at.%. The optical and electronic properties of pure and Fe-doped ZnO thin films such as refraction index, extinction coefficient, dielectric function and optical band gap energy of the layers were obtained by spectroscopic ellipsometry method in the wavelength range of 300–900[Formula: see text]nm. The incidence angle of the layers kept 70[Formula: see text]. Also data obtained by Kramers–Kronig relations were used for comparison. The influence of Fe-doping concentration on the optical and electronic properties of thin films was studied. The transmittance data of ZnO thin films showed that 6[Formula: see text]at.% Fe-doped ZnO thin film has the highest transmittance value. Dielectric function of pure ZnO films was found to be higher compared with Fe-doped ones. Also it can be deduced from the results that Fe doping influences the optical band gap energy of thin films.