Ultrafine powders containing alumina nanowires are synthesized by DC arc plasma from pure aluminium metal. Nanowires grow only when reactive gases are composed of nitrogen and less than ten percent of oxygen. Nanowire...Ultrafine powders containing alumina nanowires are synthesized by DC arc plasma from pure aluminium metal. Nanowires grow only when reactive gases are composed of nitrogen and less than ten percent of oxygen. Nanowires have the diameters ranging from 20 to 80 nm and lengths ranging from hundreds nanometers to tens of micrometers. A first assumption of the mechanism process is proposed, in which nanowires grow starting directly from the aluminium. Photoluminescence measurements show that the powders have three emission peaks around 435, 530 and 750 nm resulting from different kinds of defects such as oxygen vacancies, aluminium interstitial ions and surface defects.展开更多
Cadmium sulfide(Cd S) thin films have been prepared by a simple technique such as chemical bath deposition(CBD). A set of samples Cd S were deposited on glass substrates by varying the bath temperature from 55 to ...Cadmium sulfide(Cd S) thin films have been prepared by a simple technique such as chemical bath deposition(CBD). A set of samples Cd S were deposited on glass substrates by varying the bath temperature from 55 to 75 °C at fixed deposition time(25 min) in order to investigate the effect of deposition temperature on Cd S films physical properties. The determination of growth activation energy suggests that at low temperature Cd S film growth is governed by the release of Cd^(2+) ions in the solution. The structural characterization indicated that the Cd S films structure is cubic or hexagonal with preferential orientation along the direction(111) or(002), respectively. The optical characterization indicated that the films have a fairly high transparency, which varies between55% and 80% in the visible range of the optical spectrum, the refractive index varies from 1.85 to 2.5 and the optical gap value of which can reach 2.2 e V. It can be suggested that these properties make these films perfectly suitable for their use as window film in thin films based solar cells.展开更多
文摘Ultrafine powders containing alumina nanowires are synthesized by DC arc plasma from pure aluminium metal. Nanowires grow only when reactive gases are composed of nitrogen and less than ten percent of oxygen. Nanowires have the diameters ranging from 20 to 80 nm and lengths ranging from hundreds nanometers to tens of micrometers. A first assumption of the mechanism process is proposed, in which nanowires grow starting directly from the aluminium. Photoluminescence measurements show that the powders have three emission peaks around 435, 530 and 750 nm resulting from different kinds of defects such as oxygen vacancies, aluminium interstitial ions and surface defects.
文摘Cadmium sulfide(Cd S) thin films have been prepared by a simple technique such as chemical bath deposition(CBD). A set of samples Cd S were deposited on glass substrates by varying the bath temperature from 55 to 75 °C at fixed deposition time(25 min) in order to investigate the effect of deposition temperature on Cd S films physical properties. The determination of growth activation energy suggests that at low temperature Cd S film growth is governed by the release of Cd^(2+) ions in the solution. The structural characterization indicated that the Cd S films structure is cubic or hexagonal with preferential orientation along the direction(111) or(002), respectively. The optical characterization indicated that the films have a fairly high transparency, which varies between55% and 80% in the visible range of the optical spectrum, the refractive index varies from 1.85 to 2.5 and the optical gap value of which can reach 2.2 e V. It can be suggested that these properties make these films perfectly suitable for their use as window film in thin films based solar cells.