Electrochemical Growth of Y doped ZnO Nanorods for Use in İnverted Type Organic Solar Cells as Electron Transport Layer

Abstract

In this study, Yttrium (Y) doped and undoped Zinc oxide (ZnO) nanorods (NRs) were synthesized by the electrochemical method on indium tin oxide (ITO) substrate. Y doped and undoped ZnO-NRs were used as an electron selective layer in inverted type organic solar cell structure. Effect of Y doping in ZnO was investigated via X-ray diffraction (XRD) and scanning electron microscopy (SEM). Poly(3-hexylthiophene):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) was used as an active polymer blend. Inverted type organic solar cells were fabricated with the configuration 'ITO/Y:ZnO-NRs/P3HT:PCBM/Ag'. Active layer was coated on ZnO-NRs by using drop-casting method to completely fill the gaps between the ZnO-NRs. Short circuit current density of the solar cells was increased from 10.6 to 16.4 mA cm-2 by using 3% Y doped ZnO-NRs as electron selective layer, where as the solar cell efficiency was changed from 2.35% to 3.87%. It was experimentally found that charge injection and selection in the Zn-ONRs were improved by doping the ZnO-NRs with Y atoms. © 2019 IOP Publishing Ltd.