Thin films of copper sulphide with thickness up to 0.5 µm were deposited at 70 • C on glass substrates from a solution containing copper(II) chloride, sodium thiosulphate and dimethylthiourea. As prepared and after annealing at 200 • C in N 2 (100 millitorr), these films showed x-ray diffraction patterns matching that of the mineral covellite (CuS). Annealing the films for 1 h each at 300 • C and 400 • C in nitrogen resulted in their conversion to Cu 1.8 S (digenite) and Cu 1.96 S (chalcocite), respectively. The reduction in sulphur content of the films is evident in the x-ray florescence spectra. The sheet resistance of the films varied with annealing temperature. For a film of 0.5 µm thickness, the observed sheet resistance values are: 180 / (as prepared), 6 / (200 • C), 17 / (300 • C) and 30 / (400 • C). The low sheet resistance (and thus the high conductivity, 10 3 −1 cm −1 ) leads to a high near-infrared reflectance for the films, 65% (CuS) and 40% (Cu 1.96 S), at a wavelength of 2500 nm. Analyses of the optical band gap of the films indicate an indirect gap of 1.55 eV for CuS and Cu 1.8 S and 1.4 eV for Cu 1.96 S.

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Catalytic steam reforming of ethanol (SRE) is a promising route for the production of renewable hydrogen (H 2 ). This article reviews the influence of doping supported-catalysts used in SRE on the conversion of ethanol, selectivity for H 2 , and stability during long reaction periods. In addition, promising new technologies such as membrane reactors and electrochemical reforming for performing SRE are presented.