Showing papers by "Chhagan Lal published in 2016"
TL;DR: In this article, Modified Hummer's method was adopted for synthesis of graphene oxide (GO) and reduced-graphene oxide (rGO), and the hydrogen storage capacity of the GO/rGO sample was measured using indigenously fabricated high pressure hydrogen storage Sieverts' type volumetric setup at room temperature and pressure up to 80 bar.
88 citations
TL;DR: In this article, the effect of TiF 4 additive on the hydrogen sorption properties of MgH 2 was investigated and it was observed that the hydrogen carbonation kinetics is markedly improved by adding TiF4 additive.
59 citations
10 May 2016
TL;DR: In this paper, the impact of thermal annealing on optical properties of cadmium telluride (CdTe) thin films has been investigated, and the experimental results reveal that thermal annesaling plays an important role to enhance the optical properties.
Abstract: In this paper, the impact of thermal annealing on optical properties of cadmium telluride (CdTe) thin films is investigated. The films of thickness 650 nm were deposited on thoroughly cleaned glass substrate employing vacuum evaporation followed by thermal annealing in the temperature range 250-450 °C. The as-deposited and annealed films were characterized using UV-Vis spectrophotometer. The optical band gap is found to be decreased from 1.88 eV to 1.48 eV with thermal annealing. The refractive index is found to be in the range 2.73-2.92 and observed to increase with annealing treatment. The experimental results reveal that the thermal annealing plays an important role to enhance the optical properties of CdTe thin films and annealed films may be used as absorber layer in CdTe/CdS solar cells.
2 citations
10 May 2016
TL;DR: In this paper, the effect of thickness on optical and electrical properties of CdSe thin films is investigated and the extinction coefficient and refractive index are also calculated using a UV-Vis spectrophotometer and source meter.
Abstract: The effect of thickness on the optical and electrical properties of CdSe thin films is investigated in this paper. The films of thickness 445 nm, 631 nm and 810 nm were deposited on glass and ITO coated glass substrates using thermal evaporation technique. The deposited thin films were thermally annealed in air atmosphere at temperature 100°C and were subjected to UV-Vis spectrophotometer and source meter for optical and electrical analysis respectively. The absorption coefficient is observed to increase with photon energy and found maximum in higher photon energy region. The extinction coefficient and refractive index are also calculated. The electrical analysis shows that the electrical resistivity is observed to be decreased with thickness.
1 citations