Printed Copper Nanoparticle Metal Grids for Cost‐Effective ITO‐Free Solution Processed Solar Cells

Copper nanoparticle inks have drawn much attention since they have the potential to constitute an alternative cost‐effective solution than other noble metals nanoparticle inks such as Ag for indium tin oxide (ITO)‐free printed electronic applications. Our research and development efforts have produced high conductivity copper nanoparticle inks which have excellent jetting and printing properties resulting in high quality inkjet‐printed (IJP) Cu nanoparticle‐based metal grids. We present ITO‐free, Si‐PCPDTBT: PC[70]BM organic photovoltaics (OPVs) processed in ambient low‐cost fabrication conditions comprising for the first time embedded and non embedded inkjet‐printed copper grid/Poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the bottom electrode with power conversion efficiencies (PCE) of 2.56 and 3.35%, respectively. The results of the ITO‐free OPVs using inkjet‐printed Cu nanoparticle current collecting grids are discussed relevant to reference ITO‐based OPVs with PCE of 4.92%. The development of inkjet printed electrodes based on copper nanoparticle grid combined with PEDOT:PSS is presented, for cost effective ITO‐free solution processed organic photovoltaics.