Solution processed silver-nanowire/zinc oxide based transparent conductive electrode for efficient photovoltaic performance

Abstract

To replace expensive and scarce Indium Tin Oxide (ITO) as transparent conductive electrode (TCE) in solar cell fabrication, low-cost and solution processed metal nanowires can also be used as a TCE due to its higher conductivity and transparency. Despite of its higher conductivity and transparency, bare Silver nanowire (AgNW) film suffers due to its poor adhesion and smaller contact area with lower-lying n-type buffer layer. In this work, percolation network of AgNWs covered with scalable and solution processed ZnO film as transparent conductive electrode (TCE) is demonstrated and utilized for fabrication of CuInGaSe2 thin film solar cell. The concentration of the AgNWs in percolation network is optimized as areal mass density of AgNWs in the TCE. The conductive atomic force microscope studies are done to conclude the enhancement of current collection by covering the AgNW film with solution processed ZnO layer. The AgNW-based TCE with areal mass density of 242 mg/m2, sheet resistance 11 Ω/sq and transmittance 90% exhibited maximum conversion efficiency of 13.4% which is comparable to the efficiency obtained for vacuum based sputter deposited ITO or ZnO as TCE.