Side-chain engineering on triphenylamine derivative-based hole-transport materials for perovskite solar cells: Theoretical simulation and experimental exploration

The development of hole-transport materials (HTMs) is a significant approach to promote the power conversion efficiency (PCE) of perovskite solar cells (PSCs). Here, based on the triphenylamine (TPA) derivatives and patulous TPA derivatives as side-chains, WR1 and WR2 are designed and explored by density functional theory (DFT), time-dependent DFT (TD-DFT) in combination with Marcus electron transfer theory. The calculated results show that the WR1 exhibits matching energy levels with perovskite and better hole transporting ability in comparison with these of WR2 can save as a potential HTM for PSCs applications. In order to confirm screening results of molecular design, the WR1 as HTM in PSC device reveals that the WR1-based PSC device obtained the PCE of 20.04% higher than that of the typical Spiro-OMeTAD-based device (18.84%). Moreover, the experimental results can well verify the data of theoretical simulations. The strategy of side-chain modification on TPA derivatives-based materials is a viable method to exploit new HTMs.