Solution Processed Bi-Based Sensitized Solar Cell: Effects of Post Heat Treatment

Abstract

Nanosize semiconductors have been used as active sensitizers for the application of quantum dot-sensitized solar cells (QDSSC). “Green” sensitizers are introduced as an alternative for the toxic Cd and Pb based compounds. In this work, Bi2S3 quantum dots (QDs) were fabricated and used as sensitizers in QDSSC. QDs were grown on TiO2 electrode via solution dipping process. Although the performance of “green” QDSSC is not as high as that of CdS or CdSe based QDSSCs, its performance can be enhanced with post heat treatment. The effect is dependent on the heat treatment temperature profile where gradual increase of sintering temperature is preferred. The effects of post heat treatment on Bi2S3 sensitized TiO2 electrodes are investigated and discussed.