Recent development of conjugated oligomers for high-efficiency bulk-heterojunction solar cells

Organic solar cells (OSCs) have emerged as a cost-effective solution in fabricating large-area, lightweight and flexible devices by using simple techniques with low environmental impact. With the power conversion efficiency of polymeric bulk-heterojunction (BHJ) OSCs reaching ∼6%, pushing OSCs further to practical applications has now motivated intensified research interests in designing new material and implementing new device architecture. Conjugated oligomers have shown specific advantages in synthesis, purification and structure definition compared with polymers. Recent years have witnessed intensive research in developing high-efficiency BHJ cells with conjugated oligomers as either electron-donating materials or accepting materials. This account primarily focuses on the recent development of conjugated oligomers and their application in BHJ solar cells. The results show that these oligomeric donors or acceptors are promising to construct high efficiency BHJ solar cells.