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 re-sults 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 experi-mental 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.