Influence of different sulfur sources on the phase formation of Cu2ZnSnS4 (CZTS) nanoparticles (NPs)

• Published in: Journal of materials science. Materials in electronics 2018-06, Vol.29 (12), p.9751-9756
• Main Authors: Imla Mary, C., Senthilkumar, M., Moorthy Babu, S.
• Format: Article
• Language: English
• Subjects: Carrier density; Characterization and Evaluation of Materials; Chemistry and Materials Science; Coating effects; Copper zinc tin sulfide; Crystallography; Electrical properties; Electrical resistivity; Hall effect; Materials Science; Nanoparticles; Optical and Electronic Materials; Phases; Spin coating; Synthesis; Thin films; Thiols; Wurtzite; X-ray diffraction
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-018-9013-4

Wurtzite (Wz) and kesterite (Ks) phases of Cu 2 ZnSnS 4 (CZTS) nanoparticles (NPs) have been selectively synthesized via hot injection method using 1-octadecene (1-ODE) as solvent. The solvents, 1-dodecanethiol (1-DDT) and tert -dodecanethiol ( t -DDT) were utilized to control the reactivity of metal precursors and to tune the desirable crystallographic phases. The phase purity of the as synthesized CZTS NPs was confirmed using X-ray diffraction results. TEM images indicate that the developed nanoparticles consist of a mixture of triangular shaped (height 20 ± 3 nm, width 17 ± 2 nm) and sphere shaped NPs (13.4 ± 0.4 nm). These nanoparticles were formed due to the influence of thiols without any additional capping ligands. The band gap of as-synthesized CZTS NPs were calculated as 1.41 eV for wurtzite phase (Wz—1-DDT) and 1.47 eV for kesterite phase (Ks— t -DDT) from UV–Visible absorption results. CZTS thin films were prepared via spin coating and the electrical properties were analysed using Hall Effect measurements. Both the phases of CZTS films exhibit p-type conductivity. Wurtzite phase of CZTS has higher mobility (23.6 cm −3 ) and carrier concentration (2.64 × 10 17 ) compared to kesterite phase of CZTS films.