Boilerplate and Party Intent

In this work we examined optical and defect properties of as-grown and Ni-coated ZnO nanowires (NWs) grown by rapid thermal chemical vapor deposition by means of optically detected magnetic resonance (ODMR). Several grown-in defects are revealed by monitoring visible photoluminescence (PL) emissions and are attributed to Zn vacancies, O vacancies, a shallow (but not effective mass) donor and exchange-coupled pairs of a Zn vacancy and a Zn interstitial. It is also found that the same ODMR signals are detected in the as-grown and Ni-coated NWs, indicating that metal coatings does not significantly affect formation of the aforementioned defects and that the observed defects are located in the bulk of the NWs

Идентификация веществ раздражающего действия CS и CN в следах выстрела из газового оружия

ХРОМАТОГРАФИЯ ГАЗОВА

Preparation and characterisation of sprayed tin sulphide films grown at different precursor concentrations

Tin sulphide films have been grown by spray pyrolysis technique at different precursor concentrations varied in the range, 0.01–0.2 M keeping other deposition parameters constant. The physical properties of the deposited films were systematically studied in relation to the precursor concentration. The studies indicated that the films grown in the precursor concentration range, 0.09–0.13 M were nearly stoichiometric with the Sn, S ratio of 1.06 and exhibited only SnS phase with a strong (1 1 1) preferred orientation that belongs to the orthorhombic crystal structure. These single-phase films showed an average electrical resistivity of 32.9 \Omega cm, Hall mobility of $139 cm^2 V^{-1} s^{-1}$ and carrier density of $\sim 10^{15} cm^{-3}$. These films had an average optical band gap of 1.32 eV with an absorption coefficient greater than $10^4 cm^{-1}$. These properties demonstrated that single-phase SnS films could be used as an absorber layer in the fabrication of heterojunction solar cells

Low-cost and nontoxic highly rectifying diodes using p-type tin monosulfide (SnS) thin films and Ti/Au binary contacts

Eco-friendly and efficient rectifying p-n diodes have been developed by using cost-effective and non-toxic fin monosulfide (SnS) thin films. Chemically stoichiometric fin monosulfide (SnS) thin films followed by titanium/gold (Ti/Au) bilayer contacts were deposited on Si substrates and then, the structures were treated by rapid thermal annealing process (RTP) at different temperatures. The impact of RTP treatment on the surface morphology and chemical composition of Ti/Au contacts and SnS films along with their electrical characteristics were investigated. The electrical measurements show that as compared to untreated Si/SnS/Ti/Au structures, the heat-treated structures typically at 200 degrees C possess low electrical resistivity and contact resistance of similar to 3 x 10(-2) Omega cm and similar to 11 k Omega, respectively. Heterojunction formed between p-SnS and n-Si exhibited excellent diode characteristics and possess a high current flow in the order of milliamperes, and excellent rectification factor of 1177@ 5 V

Defects-free single-crystalline zinc oxide nanostructures for efficient photoelectrochemical solar hydrogen generation

The article reports a novel and highly efficient methodology for the development of surface defects-free zinc oxide (ZnO) nanostructures, which are highly useful for various optoelectronic and electronic devices. Using this approach, we have developed high-quality ZnO nanostructures with comparable physical and chemical properties to high-temperature grown ones. Initially, ZnO nanostructures were developed by low-temperature chemical bath deposition, and the surface defects passivated structures were obtained by atomic layer deposition of homo-molecular clusters, i.e., Zn and O atomic layers. The surface passivated ZnO nanostructures exhibited excellent chemical stoichiometry between their constituents with enhanced crystalline quality. These nanostructures also showed improved light transmittance in the wavelengths range of 450–1000 nm, and light emission in the ultraviolet region. Further, the surface passivated nanostructures exhibited remarkable device performance as photoanodes with a greatly improved photocurrent density, more than 3 times, and reduced cathodic current of 6.17 × 10−7 [email protected] V. Significantly, the light-to-dark current ratio of the PEC devices fabricated with passivated ZnO nanostructures is found to be 1761. © 2020 Hydrogen Energy Publications LLC1

Influence of seed layer orientation on the growth and physical properties of SnS nanostructures

Stoichiometric tin (II) sulfide (SnS) nano-structures were synthesized on SnS(010)/glass substrates using a simple and low-temperature chemical solution method, and their physical properties were investigated. The as-synthesized SnS nanostructures exhibited orthorhombic crystal structure and most of the nanocrystals are preferentially oriented along the <010> direction. These nanostructures showed p-type electrical conductivity and high electrical resistivity of 93 Omega cm. SnS nanostructures exhibited a direct optical band gap of 1.43 eV. While increasing the surrounding temperature from 20 to 150 degrees C, the electrical resistivity of the structures decreased and exhibited the activation energy of 0.28 eV

High-quality ZnO nanorod based flexible devices for electronic and biological applications

Vertically aligned zinc oxide nanorods (ZnO NRs) were synthesized on kapton flexible sheets using a simple and cost-effective three-step process (electrochemical seeding, annealing under ambient conditions, and chemical solution growth). Scanning electron microscopy studies reveal that ZnO NRs grown on seed-layers, developed by electrochemical deposition at a negative potential of 1.5 V over a duration of 2.5 min and annealed at 200 degrees C for 2 h, consist of uniform morphology and good chemical stoichiometry. Transmission electron microscopy analyses show that the as-grown ZnO NRs have single crystalline hexagonal structure with a preferential growth direction of < 001 >. Highly flexible p-n junction diodes fabricated by using p-type conductive polymer exhibited excellent diode characteristics even under the fold state

Surface Passivated Zinc Oxide (ZnO) Nanorods by Atomic Layer Deposition of Ultrathin ZnO Layers for Energy Device Applications

Chemically stoichiometric and electrically low-resistive high-quality zinc oxide (ZnO) nanostructures have been developed by surface passivation with atomic layer deposited ZnO layers. The impacts of homogeneous ZnO layer growth and its thickness on the physical properties ZnO nanorods were investigated. Vertically aligned ZnO nanorod structures were synthesized by two-step process, and the surface passivation was performed by atomic layer deposition ZnO at low temperatures. Surface passivated ZnO nanorods exhibit excellent improvement in crystallinity, chemical stoichiometry, optical, and electrical properties. Further, the surface passivated structures show significant enhancement in water-oxidation performance (nearly 3 orders of magnitude, i.e., μA → mA) with greatly reduced overpotentials. These investigations emphasize that surface passivation of hydrothermally grown ZnO nanostructures with the homogeneous materials can significantly enhance the structural and optical quality along with their device performance

Investigations on structural and optical properties of co-doped (Ag, Co) ZnO nanoparticles

Undoped and co-doped (Ag, Co) ZnO powders were synthesized by chemical co-precipitation method without using any capping agent. The X-ray diffraction results indicate that the undoped and co-doped ZnO powders have pure hexagonal structure and are consisting of nanosized single-crystalline particles. The size of the nanoparticles increases with increasing Ag concentration from 1 to 5 mol% as compared to that of undoped ZnO. The presence of substitution dopants of Ag and Co in the ZnO host material was confirmed by the Energy dispersive analysis of X-rays (EDAX). Optical absorption measurements indicate blue shift and red-shift in the absorption band edge upon doping concentration of Ag and blue emission was observed by photoluminescence (PL) studies