Two methoxyaniline-substituted dibenzofuran derivatives as hole-transport materials for perovskite solar cells

Abstract

2,2′,7,7′-Tetrakis(N,N-di-p-methoxyphenylamine)-9,9′-spirobifluorene (Spiro-OMeTAD), one of the classical organic photoelectric materials, has been widely used as a hole transport material (HTM) in perovskite solar cells (PSCs) due to its relatively higher conductivity, easier film formation, weak absorption in the visible region, etc. However, the complex synthesis process and the high synthesis cost of Spiro-OMeTAD severely limit the commercialization of this material. In this work, two economical methoxyaniline-substituted dibenzofuran derivatives, BF-002 and BF-003, are synthesized and successfully used as hole-transport materials in perovskite solar cells (PSCs). The important properties including light absorption, thermal stability, energy level, conductivity, as well as photovoltaic performance are systematically demonstrated. The highest power conversion efficiencies of the PSCs based on BF-002 and BF-003 are 14.20% and 14.07%, respectively, comparable to that of the PSCs based on Spiro-OMeTAD.