Benzodithiazole‐Based Hole‐Transporting Material for Efficient Perovskite Solar Cells

We have designed and synthesized a family of three novel benzodithiazole‐based hole‐transporting materials (HTMs) named as BTT‐TPA, BTT‐OMe and BTT‐Me. These new HTMs are characterized by using 1H, 13C NMR, FTIR, elemental analysis, UV‐Vis spectrophotometer, and cyclic voltammetry. The photovoltaic performances of these HTMs were successfully evaluated in perovskite solar cells (PSCs). Consequently, the PSCs based on BTT‐TPA, BTT‐Me and BTT‐OMe HTMs showed Jsc of 12.81 mA cm−2, 11.87 mA cm−2, 13.85 mA cm−2, Voc of 0.88 V, 0.83 V, 0.87 V, a FF of 0.62, 0.63, 0.63 and the overall power conversion efficiency of (η) 6.99%, 6.20% and 7.44%, respectively. The easy synthetic route and purification technique provides the viability of these HTMs as future PSCs development. Solar cells: Three simplest benzodithiazole‐based hole‐transporting materials (HTMs) named as BTT‐TPA, BTT‐OMe and BTT‐Me have been designed and synthesized. Among them BTT‐OMe exhibited high power conversion efficiency of 7.46%. This study will provide the way on how to design simplest HTMs compared to Spiro‐OMeTAD.