Che Boreal | IPN - Academia.edu (original) (raw)
Address: Mexico, Distrito Federal, Mexico
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Papers by Che Boreal
Forest Ecology and Management, 2007
Chemical and structural characterization has been performed for thick (1 00-600 lain) and thin (1... more Chemical and structural characterization has been performed for thick (1 00-600 lain) and thin (10-1 O0 pm) 2H/4H inter-polytype SnS2 crystals grown by low-temperature chemical vapour transport in the reverse temperature gradient geometry. X-ray diffraction shows that the 2H/4H-SnS2 phase transforms to single-crystal 2H-SnS 2 in 6-1 2 months. The S/Sn ratio is 2.02 _+ 0,01 in thick crystals and 2.01 + 0.01 in thin crystals. Thermogravimetric/differential thermal analysis and the other characterization techniques show no difference between the two types of crystal. Extremely small quantities of carbon and oxygen and some chlorine were detected by secondary ion mass spectroscopy and/or X-ray photoelectron spectroscopy (XPS). These elements are concentrated at the surface. The XPS data show a chemical shift of tin and sulphur in the surface layer, which is probably caused by the adsorbed carbon and oxygen; however, it cannot be explained by the formation of the usual oxides of tin and sulphur.
Chemical methods are nowadays very attractive, since they are relatively simple, low cost and con... more Chemical methods are nowadays very attractive, since they are relatively simple, low cost and convenient for larger area deposition of thin films. In this paper, we outline our work related to the synthesis and characterization of some wide band gap semiconducting material thin films prepared by using solution methods, namely, chemical bath deposition and successive ionic layer adsorption and reaction (SILAR). The optimum preparative parameters are given and respective structural, surface morphological, compositional, optical, and electrical properties are described. Some materials we used in solar cells as buffer layers and achieved remarkable results, which are summarized. r
Forest Ecology and Management, 2007
Chemical and structural characterization has been performed for thick (1 00-600 lain) and thin (1... more Chemical and structural characterization has been performed for thick (1 00-600 lain) and thin (10-1 O0 pm) 2H/4H inter-polytype SnS2 crystals grown by low-temperature chemical vapour transport in the reverse temperature gradient geometry. X-ray diffraction shows that the 2H/4H-SnS2 phase transforms to single-crystal 2H-SnS 2 in 6-1 2 months. The S/Sn ratio is 2.02 _+ 0,01 in thick crystals and 2.01 + 0.01 in thin crystals. Thermogravimetric/differential thermal analysis and the other characterization techniques show no difference between the two types of crystal. Extremely small quantities of carbon and oxygen and some chlorine were detected by secondary ion mass spectroscopy and/or X-ray photoelectron spectroscopy (XPS). These elements are concentrated at the surface. The XPS data show a chemical shift of tin and sulphur in the surface layer, which is probably caused by the adsorbed carbon and oxygen; however, it cannot be explained by the formation of the usual oxides of tin and sulphur.
Chemical methods are nowadays very attractive, since they are relatively simple, low cost and con... more Chemical methods are nowadays very attractive, since they are relatively simple, low cost and convenient for larger area deposition of thin films. In this paper, we outline our work related to the synthesis and characterization of some wide band gap semiconducting material thin films prepared by using solution methods, namely, chemical bath deposition and successive ionic layer adsorption and reaction (SILAR). The optimum preparative parameters are given and respective structural, surface morphological, compositional, optical, and electrical properties are described. Some materials we used in solar cells as buffer layers and achieved remarkable results, which are summarized. r