The Viability of Spectral Splitting for the Reduction of Recombination Losses in Multi-Bandgap Solar Photovoltaic Devices

Abstract

As the search intensifies to produce low-cost high-efficiency solar photovoltaic cells, several device designs have been proposed to split the solar spectrum and focus only photons of a bandgap appropriate for a given absorber layer in a sub-cell or graded bandgap cell. The intention of such designs is to decrease the electrical path length of charge carriers and the concomitant recombination losses observed in conventional tandem multi-bandgap devices. This article explores the viability of such spectral splitting photovoltaic designs by investigating amorphous silicon and microcrystalline silicon tandem and individual cells using numerical simulation with D-AMPS