Spectral conversion by silicon nanocrystal dispersed gel glass: efficiency enhancement of silicon solar cell

Abstract

Alongside the quest for new materials for development of next-generation solar cells, increasing the efficiency of the existing crystalline silicon-based photovoltaic module is of paramount importance. In this work we prepared a silicon nanocrystal (NC) dispersed gel-glass and used it as a luminescent down shifting material to enhance the efficiency of a conventional solar cell module. The synthesized gel-glass efficiently converts the unutilized high energy UV photons of the solar spectrum to blue-green photons and renders them amenable for effective carrier generation. An exceptionally high quantum yield (42.8%) of photon down conversion could be achieved with the luminescent silicon NCs. Following the insertion of the NC embedded gel-glass, the relative photon conversion efficiency and the short circuit current of the solar cell were found to increase by 6.48% and 4.2%, respectively. Further improvement of solar cell efficiency using this material could be achieved by optimized design and deposition and by optimizing the formation parameters of the gel-glass.