(Invited)Improved Interfaces in Multilayered Organic-Inorganic Hybrid Solar Cells with π-Conjugated Polymers-Antimony Sulfide-Strontium Titanate-Titanium Oxide

Abstract

Organic-inorganic hybrid solar cells composed of glass/F-doped SnO2/TiO2/ SrTiO3/Sb2S3/ poly[(3-hexylthiophene)-2,5-diyl]/poly[3-(3-carboxypropyl)thiophene-2,5-diyl]/Au have been prepared and evaluated their photovoltaic performance. Insertion of SrTiO3 layer between TiO2 and Sb2S3 interface resulted in the enhancement of the open circuit voltage (Voc) from 0.61 V to 0.70 V. The thickness, surface roughness, and sea-island structures of the Sb2S3 layer were optimized in terms of transmittance, reflectivity, short circuit current density (Jsc), fill factor (FF) and power conversion efficiency (PCE) by changing the precursor concentration and rotation speed for spin-coating of the Sb2S3 layer. Through the above optimization, enhancements of Jsc from 8.6 mA cm-2 to 13.6 mA cm-2 and FF from 0.56 to 0.61 in addition to the improvement of PCE from 3.0% to 6.1% as compared with the device without the SrTiO3 layer were achieved.