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Amir Hussain

Bio: Amir Hussain is an academic researcher from Gauhati University. The author has contributed to research in topics: Thin film & Nanocrystalline material. The author has an hindex of 7, co-authored 12 publications receiving 162 citations.

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Journal ArticleDOI
TL;DR: It was found that average crystallite size, as calculated from Scherrer’s formula, increased from 23 to 33 nm as the deposition temperature was varied from 303 to 343 K, and the dislocation density and microstrain were found to vary inversely with the crystalliteSize, whereas the lattice constant was found to increase with an increase in crystallite Size.
Abstract: Nanocrystalline lead selenide (PbSe) thin films were prepared on glass substrates by a chemical bath deposition method, using sodium selenosulfate (Na2SeSO3) as a source of Se2− ions, and lead acetate as a source of Pb2+ ions. Trisodium citrate (TSC) was used as a complexing agent. PbSe films were prepared at various deposition temperatures while the pH value was kept fixed at 11, and the effect on the resulting film properties was studied by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM) and optical absorption studies. The structural parameters, such as the lattice constant (a), crystallite size (D), dislocation density (ρ) and microstrain (e) were evaluated from the XRD spectra. It was found that average crystallite size, as calculated from Scherrer’s formula, increased from 23 to 33 nm as the deposition temperature was varied from 303 to 343 K. The dislocation density and microstrain were found to vary inversely with the crystallite size, whereas the lattice constant was found to increase with an increase in crystallite size. The optical absorption spectra of the nanocrystalline PbSe films showed a blue shift, and the optical band gap (Eg) was found to increase from 1.96 to 2.10 eV with the decrease in crystallite size.

81 citations

Journal ArticleDOI
TL;DR: In this paper, Nanocrystalline lead sulphide thin films were deposited on clean glass substrates by chemical bath deposition technique using lead acetate and thiourea as Pb+2 and S−2 ions source respectively.
Abstract: Nanocrystalline lead sulphide thin films were deposited on clean glass substrates by chemical bath deposition technique using lead acetate and thiourea as Pb+2 and S−2 ions source respectively. Films of five different molarities (0.05 M–0.150 M) of same pH value 10.5 were prepared at 318 K. Characterization was carried out using X-ray diffraction (XRD), X-ray fluorescence, scanning electron microscopy, optical absorption and electrical conductivity measurements. Average crystallite size calculated from the XRD spectra using Scherrer’s formula were between 13 and 18 nm. The optical absorption spectra shifted towards the lower wavelength. The band gap energy of 2.13–2.44 eV was determined from the optical absorption spectra. The electrical conductivity measured using two co-planar Aluminium electrodes was found to increase with increase in temperature showing semiconducting nature of the films. The electrical conductivity at room temperature was found to be of the order of 10−4 Ω−1 cm−1.

31 citations

Journal ArticleDOI
TL;DR: In this paper, Nanocrystalline PbS thin films were deposited on clean glass substrates by chemical bath deposition technique using lead acetate and thiourea as Pb2+ and S2− ions source, respectively.
Abstract: Nanocrystalline PbS thin films were deposited on clean glass substrates by chemical bath deposition technique using lead acetate and thiourea as Pb2+ and S2− ions source, respectively. PbS films of five different molarities (0.05–0.150M) were prepared at pH (10.5 and 11) and deposition temperature (318 and 333 K). The structural characterization of the films was carried out by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM).The structural parameters such as crystallite size, lattice constant, dislocation density and micro strain have been evaluated from the XRD spectra. The average crystallite sizes were found between 13 and 21 nm. XRF gave the presence of Pb and S in the prepared films. The surface morphology of the films was known from the SEM photographs.

20 citations

Journal ArticleDOI
TL;DR: In this paper, Bismuth sulfide was prepared in PVA matrix by chemical method using solutions of Bi(NO3)3 and Na2S. Both doped and undoped Bi2S3-PVA films were characterized by SEM, XRF, optical absorption and electrical conductivity measurements.
Abstract: Bismuth sulfide was prepared in PVA matrix by chemical method using solutions of Bi(NO3)3 and Na2S. Bi2S3 was doped during preparation using Br2 vapour and also liquid drops of Br2. Both doped and undoped Bi2S3–PVA films were characterized by SEM, XRF, optical absorption and electrical conductivity measurements. The undoped films consisted of particles of sizes 156 nm-184 nm as revealed by SEM micrographs. The films doped with Bromine (Br2) vapour were found to consist of rods of diameters ranging from 75 nm to 80 nm. The films doped with Br2 liquid drops showed rods of diameters ranging from 4843 nm to 6930 nm. XRF spectra confirmed the presence of bismuth, sulfur and bromine in the doped films. The temperature variation of doped and undoped films in the temperature range from 298 K to 383 K shows more or less similar pattern of variation with two regions of conduction. The band gap obtained from the absorption spectra was found to change from 3.61 eV to 3.78 eV and the absorption edge shifted towards the lower wavelength with decrease in diameter of the particles or rods.

18 citations

Journal ArticleDOI
TL;DR: In this article, Nanocrystalline Bi 2 S 3 thin films are deposited on tin chloride treated glass substrate from the solution containing bismuth nitrate, triethanolamine (TEA), and thioacetamide (TAM) at a bath temperature 318 K. The prepared films are subsequently annealed at different temperatures for studying the effect of thermal treatment on the structural, surface morphology, optical and electrical properties of the films.

16 citations


Cited by
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Journal ArticleDOI
TL;DR: Mao and Hwang as mentioned in this paper reviewed charge transport, carrier injection, photoelectronic processes and luminescence in semiconductors and insulators, with a focus on charge transport.
Abstract: K C Mao and W Hwang 1981 Oxford: Pergamon xvi + 663 pp price £50 This seven-chapter book reviews charge transport, carrier injection, photoelectronic processes and luminescence in semiconductors and insulators. The subtitle reference to organic semiconductors applies to the first chapter on charge transport and the final two chapters on photoelectronic and luminescence topics.

77 citations

Journal ArticleDOI
TL;DR: In this paper, a plasmonic semiconductor photocatalyst has been successfully developed in a mixed solvothermal environment, and the photocatalytic abilities of the as-prepared samples are examined by the photocATalytic reduction of Cr(VI) and oxidation of tetracycline (TC).

70 citations

Journal ArticleDOI
TL;DR: In this paper, the structural, electrical and optical properties of (PVA-PEG-PVP-Fe3O4) magnetic nanocomposites have been investigated and the results showed that the D.C., A.C. and attenuation coefficients of gamma radiation increase with increase in nanoparticles concentration.
Abstract: Preparation of (PVA-PEG-PVP-Fe3O4) magnetic nanocomposites and studying their structural, electrical and optical properties have been investigated. The results showed that the D.C., A.C. electrical and optical properties of (PVA-PEG-PVP) blend are improved with increase in Fe3O4 nanoparticles concentration. The (PVA-PEG-PVP-Fe3O4) nanocomposites tested for thermal energy storage and release, gamma ray shielding, antibacterial activity and humidity sensors applications with high quality, lightweight and good elastic. The results of showed that the melting and solidification time for thermal energy storage and release decrease with adding Fe3O4 nanoparticles concentrations. The attenuation coefficients of gamma radiation increase with increase in nanoparticles concentration. The inhibition zone for antibacterial application increases with increase in Fe3O4 nanoparticles concentration. The nanocomposites have highly sensitivity for humidity.

67 citations

Journal ArticleDOI
TL;DR: In this article, the bismuth-based nanoprobe has been regarded as the most promising X-ray computed tomography probe due to its largest Xray attenuation coefficient.
Abstract: The development of the advanced imaging probe holds the key to the achievement of target imaging and metastasis tracing. The bismuth based nanoprobe has been regarded as the most promising X-ray computed tomography probe due to its largest X-ray attenuation coefficient. Accordingly, the bismuth nanoparticles with controllable size distribution and light weight have been fabricated through a one pot synthesis strategy. The surface modification can be easily conducted with the polyethylene glycol to make the nanoparticles hydrosoluble and biocompatible. More importantly, the Bi nanoparticles can be excited by light to conduct excitation wavelength dependent emission in the visible (Vis) and near-infrared (NIR) region, which makes it possible to utilize it for fluorescence imaging. Under the detection of the multimode CT/fluorescence imaging, the long circulation time of the Bi nanoparticles and its specific accumulation at the liver and intestine can be visually displayed. The facile and large scale prepara...

61 citations

Journal ArticleDOI
TL;DR: In this article, the influence of annealing time on the structure, composition, morphology, and optical properties of the processed precursor films has been studied in detail, and it was shown that a longer annaling time during CMTS growth can improve the phase purity, promote the preferred orientation along the (112) direction, and enhance grain growth in the micrometer range.
Abstract: Earth-abundant Cu2MnSnS4 (CMTS) thin films were fabricated through a non-toxic spin-coating technique. The precursor solution is based on a 2-methoxyethanol solvated thiourea complex with acetyl-acetone used as an additive agent, and the spin-coated films were post-annealed at 570 °C under a N2 atmosphere. The influence of annealing time on the structure, composition, morphology, and optical properties of the processed precursor films has been studied in detail. We found that a longer annealing time during CMTS growth can improve the phase purity, promote the preferred orientation along the (112) direction, and enhance grain growth in the micrometer range. Film annealed for 10 min gives a pure CMTS phase, whereas other films annealed for lower and/or higher than 10 min (especially 13 min) can form secondary phases (i.e., SnS, MnS). The band gap energy is estimated as 1.63–1.18 eV for post-annealed films depending on the heat treatment, compared to 1.69 eV for as-prepared film. An efficiency of 0.49% for the device fabricated here has been achieved with an open-circuit voltage of 308.4 mV, a short-circuit current density of 4.7 mA cm−2, and a fill factor of 33.9%. It offers a new research direction for the application of a CMTS absorber layer in low-cost solar cells.

48 citations