摘要

N-Heteroacene materials offer great promise for efficient organic solar cells (OSCs) because of their broad and tunable light absorption and excellent charge mobility. However, few attempts have been made to apply them in OSCs. Here, we first report the synthesis of all-thiophene-substituted N-heteroacenes, B2AT and B2A2T. These small molecules possess good physical and electrical performances, such as high solubility and thermal stability, relatively favorable optical and hole transport properties for OSCs, and low-lying HOMO levels, which make them potential candidates for application in OSCs as electron-donor materials. The bulk heterojunction solar cell with a thin film of B2AT or B2A2T:PC71BM exhibits a high open-circuit voltage of 1.02 and 1.00 V, leading to a power conversion efficiency of 4.82% and 5.39%, respectively, which is the best performance achieved to date for N-heteroacene based OSCs. This clearly demonstrates the potential of N-heteroacenes for efficient photovoltaic devices.