Fully solution processed all inorganic nanocrystal solar cells

The effects of solution (sol) processed contacts of indium tin oxide (ITO-sol) and gold (Au-sol) on solar cells are tested. When combined with solution processed active layers of CdTe/CdSe, all-inorganic fully solution processed solar cells are produced on non-conductive glass substrates. Under AM 1.5G illumination, open circuit voltages (Voc), short circuit currents (Jsc) and efficiencies (η) of solar cells processed with evaporated Au and commercial ITO were found to be (Voc = 0.56 ± 0.04 V, Jsc = 17.2 ± 2.2 mA cm(-2), η = 3.8 ± 0.4%), with Au-sol replacement (Voc = 0.54 ± 0.03 V, Jsc = 12.6 ± 1.0 mA cm(-2), η = 2.0 ± 0.1%), with ITO-sol (Voc = 0.38 ± 0.04 V, Jsc = 12.3 ± 0.8 mA cm(-2), η = 1.3 ± 0.2%), and with each layer solution processed (Voc = 0.49 ± 0.01 V, Jsc = 10.0 ± 1.5 mA cm(-2), η = 1.5 ± 0.2%) with the champion fully-solution processed all-inorganic device showing η = 1.7%. Layers and devices were characterized with UV/Vis spectroscopy, optical profilometry, XRD, XPS and SEM. The results indicate that the reduced performance of the all-solution devices results primarily from increased roughness of the Au film and decreased conductivity of the ITO layer.