The University of Manchester, UK
Tahani received MSci degree in nonotechnology and microsystms at heriot-watt university. She is curruntly styding her PhD at the universty of manchester with Prof. Paul O'Brien where her work focuses on metal chalcogenides for photovoltaic applications.
Antimony(III) ethylxanthate [Sb(S2COEt)3] and bismuth(III) ethylxanthate [Bi(S2COEt)3] were used as a single source precursor for the preparation of Sb2S3 and Bi2S3, respectively, by a melt method at different temperatures. In addition, the thermogravimetric analysis reveals that both precursors exhibit complete decomposition in similar temperature range. Therefore, the mixture of these precursors can be used to produce solid solutions of Bi-Sb-S between the two phases (Bi2S3 and Sb2S3). A series with varying stoichiometry was synthesized by using different molar ratios (i.e. Sb/Sb+Bi = 0.2, 0.4, 0.6 and 0.8). The XRD peaks at all ratios correspond well to the orthorhombic crystals, where the peaks fall in between those of orthorhombic Bi2S3 and orthorhombic Sb2S3 for Bi-Sb-S system. The gradual splitting and shift in the peaks position confirms the successful incorporation of antimony into bismuth sulfide. The inclusion of antimony was further confirmed by change in lattice parameters and is in good agreement with the literature values. A decrease of almost 3.5 % in volume was observed as moving from Bi2S3 to Sb2S3. A change in all lattice parameters indicates that the substitution is random and not in any specific direction. The elemental compositions of all the samples were examined via EDX analysis and ICP- OES, which shows uniform distribution of elements in all samples. The morphology for all the samples was observed using SEM, revealing different morphologies as the composition changes from Bi2S3 to Sb2S3.