我們設計並合成一系列以bimestylene為核心，連接不同π-共軛長度之電子予體的電洞傳輸材料（HTMs）P1、P2和P3，應用在鈣鈦礦太陽能電池中。P1、P2和P3的熱裂解溫度（Td）分別為350 ℃、378 ℃、366 ℃，玻璃轉移溫度（Tg）分別為115 ℃、112 ℃、156 ℃，顯示具有良好的熱穩定性。另外，三個化合物之氧化電位隨著π-共軛增長而降低。以P系列做為鈣鈦礦太陽能電池之電洞傳輸材料所量測之光電轉換數值分別為P1 10.88 % （Jsc=16.43 mA cm-2，Voc=0.975 V，FF=0.679）、P2 9.31 % （Jsc=17.98 mA cm-2，Voc=0.910 V，FF=0.569）、P3 3.66 % （Jsc=13.74 mA cm-2，Voc=0.710 V，FF=0.374）。結果顯示，以bimestylene為核心之新型電洞傳輸材料可有效應用在鈣鈦礦太陽能電池中。
we report the synthesis and characterization of three bimesitylene-core arylamine derivatives P1, P2, and P3 as new hole transporting materials (HTMs) and their application in CH3NH3PbI3 perovskite solar cell. The bulky and twisted structure of bimesityl has some similarity to that of spiro-OMeTAD and provides high thermal stability, high glass transition temperature (Tg) and high solubility in common organic solvents. The absorption, electrochemical, and photovoltaic properties for all HTMs have been systematically investigated. The π-conjugated length of the donor significantly influenced the electrochemical and photovoltaic properties of the HTMs. The short-circuit current density (Jsc) was 16.43 mA cm-2 with an open-circuit voltage (Voc) 0.975 V and a fill factor (FF) 0.679, that corresponded to a power-conversion efficiency (η) 10.88 % for P1. The short-circuit current density (Jsc) was 17.98 mA cm-2 with an open-circuit voltage (Voc) 0.910 V and a fill factor (FF) 0.569, that corresponded to a power-conversion efficiency (η) 9.31 % for P2. The short-circuit current density (Jsc) was 13.74 mA cm-2 with an open-circuit voltage (Voc) 0.710 V and a fill factor (FF) 0.374, that corresponded to a power-conversion efficiency (η) 3.66 % for P3. The small molecule hole transport materials facilitates the fabrication process and thus potentially reduces the fabrication cost of perovskite solar cell.
