Electrodeposited semiconductors at room temperature: an X-ray Absorption Spectroscopy study of Cu-, Zn-, S-bearing thin films

摘要: Abstract A SEM, DRS and XAS study was carried out on ultra-thin films with chemical composition belonging to the Cu-Zn-S ternary system, related kesterite-type materials, in light of their potential application thin film photovoltaic technology. The films, realized through layer-by-layer E-ALD electrochemical technique, reveal variable phase as a function applied sequence. In particular, by increasing Zn cycles per Cu cycle from 1:1 9:1, number detected phases changes 3 2. all samples, mainly crystallize 2 S type phase, whereas occurs ZnS. sample, additional ZnO is detected. parallels apparent sample morphology. sulphide covered net elongated nanostructures, length which decreases cycle. All these evidences are interpreted due operating route during synthesis confirm lack miscibility between ZnS, thermodynamically relevant after has stopped. band gap values exhibited three modulated changing copper:zinc ratio, progressively approach value useful for solar energy conversion, thus strongly proposing new sulfide nanomaterials photovoltaics photochemical applications.