Solution processed approaches for bulk-heterojunction solar cells based on Pb and Cd chalcogenide nanocrystals

Abstract

The development of inorganic nanocrystals (NCs) based bulk-heterojunction (BHJ) solar cells provides an alternative way to harvest sunlight for energy conversion. BHJ solar cells attract significant interest due to their simple fabrication, low cost and high performance. Among all the inorganic NCs, Pb and Cd chalcogenide (PbX and CdX, X=S, Se or Te) NCs as electron acceptor materials theoretically improve the performance of BHJ solar cells due to their enhanced absorption and multiple exciton generation (MEG). However, their performance in BHJ solar cell devices still does not match with the BHJ solar cell devices made from phenyl-C61-butyric acid methyl ester (PCBM). The initial part of this review introduces the concept, materials, structure, device fabrication, working principles and characterization of BHJ solar cells. Then, the different solution processed approaches and details on reported BHJ solar cell devices based on Pb and Cd chalcogenide NCs are summarized. Finally, critical factors limiting the performance of BHJ solar cell devices are discussed and strategies for the improvement of the power conversion efficiency (PCE) are demonstrated by presenting recent examples from literature.