Polycrystalline thin films of antimony selenide via chemical bath deposition and post deposition treatments

Abstract

We report a method for obtaining thin films of polycrystalline antimony selenide via chemical bath deposition followed by heating the thin films at 573 K in selenium vapor. The thin films deposited from chemical baths containing one or more soluble complexes of antimony, and selenosulfate initially did not show X-ray diffraction (XRD) patterns corresponding to crystalline antimony selenide. Composition of the films, studied by energy dispersive X-ray analyses indicated selenium deficiency. Heating these films in presence of selenium vapor at 573 K under nitrogen (2000 mTorr) resulted in an enrichment of Se in the films. XRD peaks of such films matched Sb 2 Se 3. Evaluation of band gap from optical spectra of such films shows absorption due to indirect transition occurring in the range of 1-1.2 eV. The films are photosensitive, with dark conductivity of about 2 Â 10 À 8 (V cm) À 1 and photoconductivity, about 10 À 6 (V cm) À 1 under tungsten halogen lamp illumination with intensity of 700 W m À 2. An estimate for the mobility life time product for the film is 4 Â 10 À 9 cm 2 V À 1 .

A comparative study on the electronic and optical properties of Sb-=SUB=-2-=/SUB=-Se-=SUB=-3-=/SUB=- thin film

“…5, g), respectively. Table 2 it is clear that the obtained direct band gap is in good agreement with SE and UV-vis as well as reported values [26,[33][34][35][36] while indirect band gap is consistent with UV-vis, theoretical and the reported values [35,36,38]. However, the theoretical value is a little bit smaller than the experimental values due to exchange correlation [53] and the formation of nanocrystalline after annealing could be introduced quantum size effect.…”

“…Although, Sb 2 Se 3 is used in various fields, the lack of proper knowledge regarding its electronic structure and optical properties sometimes leads to contradictory interpretations of the experimental data found in literature [26]. Regarding the direct/indirect band gap nature a few contradictory reports are available in literature: 1.0 to 1.82 eV for single crystals [27][28][29][30][31], for thin films direct (1.5−2.14) eV [32][33][34], indirect transitions (1−1.2) eV [35][36][37][38][39], and the theoretical indirect band gap energy of 1.21 eV using density functional theory (DFT) within the obtained gradient approximation (GGA) with GW corrections [26], as well as 0.99 eV (indirect)−1.07 eV (direct) obtained using DFT with LDA [40].…”

Atomic Layer Growth of InSe and Sb2Se3 Layered Semiconductors and Their Heterostructure

“…It has received attention as a thermoelectric material, and recently as a light sensitizer in photovoltaic devices because of its narrow band gap of about 1.1 eV-1.3 eV, which approaches the ideal Shockley−Queisser value [24][25][26]. These films have been produced via a number of methods, including thermal evaporation, chemical bath deposition, spray pyrolysis, pulsed laser deposition and electrochemical deposition [25,[27][28][29][30].…”

MS07116 Sodium Selenosulfate Synthesis and Demonstration of Its In Vitro Cytotoxic Activity Against HepG2, Caco2, and Three Kinds of Leukemia Cells

“…1). The reaction is typically conducted by refluxing a mixture of 5 mM bulk powder of black elemental selenium and 20 mM sodium sulfite for 3 h at 90°C [12,13]. Nanoparticles have huge surface area that renders a chemical reaction faster as compared with bulk powder; therefore, it could be extrapolated that sodium selenosulfate may be rapidly obtained if black elemental selenium is substituted by nanoparticles of red elemental selenium (Nano-Se).…”