Optical, electrical and structural characterization of chloride-doped ZnO nanopillars obtained by electrodeposition

Efficiency Improvements in Solution‐Based CuInS2 Solar Cells Incorporating a Cl‐Doped ZnO Nanopillars Array

“…Figure b shows a blue shift in the absorption edge of the NP‐ZnO when doping with chloride. This behavior is in accordance with previously reported shifts on the absorption edge with the Cl − /Zn 2+ ratio . The shift is due to band filling effects (and eventual bandgap renormalization) originated in the excess of free electrons due to doping, that is Moss‐Burstein effect …”

“…The E g values obtained for these samples were close to those expected for the bulk materials . In the particular case of SP‐ZnO and SP‐ZnO/NP‐ZnO, both present similar values of E g .…”

“…In turn, the nanopillars can be doped with chlorides (NP‐Cl:ZnO). Cl incorporation was confirmed by Electron Dispersion Spectroscopy (EDS), X‐rays Diffraction, and UV–Vis Spectroscopy, as described elsewhere …”

“…Each individual layer was deposited directly over a FTO/glass substrate. Interference oscillations present in both the FTO/glass substrate and the SP‐ZnO layer could lead to an increase in the interference phenomena in the SP‐ZnO transmittance spectra, explaining transmittance values above 100% . These interference oscillations are expected due to the compact nature of the SP‐ZnO layer, and its effect is reduced as the number of layers is increased …”

“…Kärber et al reported a nanostructured ZnO/In 2 S 3 /CuInS 2 superstrate solar cell with all the layers deposited by chemical spray pyrolysis, where the introduction of nano‐columnar ZnO increased the conversion efficiency from 2 to 3%. In our recent paper, nanopillars of ZnO have been doped with chloride ions to increase the free electron density . The present work focuses on the positive influence of this chloride‐doped nanostructed ZnO layer on the efficiency of a photovoltaic solar cell.…”