Solution-processed Silicon Hybrid Heterojunction Photovoltaics with Silver Nanowires

Abstract

An Organic/inorganic hybrid solar cells are cheap alternatives to conventional silicon-based solar cells. The devices take the advantages of high optical absorption and carrier mobility of inorganic semiconductors, while maintaining the easy processing attributes of polymers or other soft materials. However, the conduction of holes has been a major technical barrier for the advance of such novel devices. In this study, we propose the use of silver nanowires (AgNWs) to improve the series resistance of the hybrid solar cells and further to realize solution-processed silicon-based photovoltaics. The hybrid silicon heterojunction solar cells are demonstrated based on the composite of conductive polymer PEDOT:PSS directly spun-cast on a micro-textured n-type crystalline silicon wafer, followed by the Meyer rod coating of AgNWs as the frontal metal contacts. The cross linked AgNWs offer high transparency and low sheet resistance, which can be easily fabricated using low-cost and non-toxic materials. Moreover, the industrial-standard microscale surface textures improve the antireflection and carrier collection without increasing much surface recombination. As a result, the device current density-voltage characteristics reveals a high power conversion efficiency of 6.8% under a calibrated illumination intensity of 1000 W/m(2) of the AM1.5G solar spectrum, shedding light into the attainment of rapid solution processed silicon hybrid heterojunction solar cells.