| 초록 |
The efficiency of the perovskite solar cells (PSCs) depends on hole transport materials (HTMs), because HTMs affect hole mobility and energy level matching with perovskite valence band as well as long-term stability of the cell by oxygen and moisture. Moreover, the dopants used in HTMs have the problem of absorbing moisture in the air and damaging the perovskite structure. we designed and synthesized new dopant-free D-π-A structured HTMs by using asymmetrical π-bridge and triazatruxene core and malononiltrile acceptor. The planar structure of triazatruxene core is favorable to obtain high hole mobility by increasing π-π stacking, and the use of asymmetrical thieno[3,2-b]benzothiophene(TBT) and thieno[3,2-b]indole(TI) π-bridges is beneficial to enhance the solubility of HTMs and to make their thin film formation. In this study, we have mainly investigated the effect of asymmetrical π-bridges in star-shaped D-π-A structured dopant-free HTMs on photovoltaic performance. |
