Optical Whispering Gallery-Enabled Enhanced Photovoltaic Efficiency of CdS-CuInS2 Thin Film-Sensitized Whisperonic Solar Cells

Composite photoanode comprising mesoporous microspheres with a smooth spherical morphology exhibiting high light scattering due to optical whispering gallery modes (WGMs) is used to fabricate whisperonic solar cell (WSC) devices. The photoanode is sensitized with CdS-CuInS2 thin films (CdS-CIS-TF) of similar to 5 nm thickness. CdS-CIS-TF-sensitized photoanodes exhibit strong coupling with WGM. These WSC devices show an average (eta(avg)) efficiency (eta) of in comparison with eta(avg) approximate to 1.9% for the nanoparticulate-based photoanode. The observed efficiency is the highest for CdS-CIS-TF-sensitized solar cells made using I-/I-3(-) electrolyte. This remarkable increase in eta(avg) (similar to 60%) is attributed to increased photon absorption by the sensitizer films because of the presence of WGM scattering prevailing in smooth microspheres. Thus, WSC photoanode configuration is a promising approach to enhance the efficiency of TF-sensitized solar cells.