Molecularly engineering of truxene-based dopant-free hole-transporting materials for efficient inverted planar perovskite solar cells

摘要

In this work, four new truxene-based hole-transporting materials (HTMs) have been synthesized and applicated in the inverted perovskite solar cells (PSCs). The impact that the length of alkyl and periphery arylamine on the photophysical, electrochemical and hole transporting properties has been systematically investigated. These new HTMs exhibit decent hole mobility of 10(-3) cm(2) V-1 S-1, which ensure efficient hole extraction in dopant-free devices. PSC using the dopant-free M118 achieves a power conversion efficiency of 17.1%, which is much higher than the value of 14.4% achieved using poly (3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). Importantly, PSCs based on these truxene HTMs exhibit significantly enhanced durability under UV light. This work reveals that the adjustment of length of alkyl as well as periphery arylamine is necessary for development of stable and efficient truxene HTMs.