| Popis: |
Because single crystals (SCs) contain less defects, perovskite solar cells (PeSCs) prepared with SCs should ideally exhibit higher efficiencies. Most of the crystallization methods proposed so far, however, require an interfacial layer to modify the surface property of the substrates to facilitate the diffusion of the precursor ions. The resistance of the interfacial layer, which often also serves as charge transport layers, inevitably increases the series resistance of the solar cells, thereby limiting the performance. Herein, we dope the interfacial layer, which is also a hole-transport layer (HTL) in our cells, with p-type organic molecules to reduce their resistances and find the power conversion efficiencies (PCEs) of the single-crystal PeSCs are significantly improved. At the optimal concentration, the PCE is improved to 14.99%; the champion PCE is up to 15.67%. The results indicate that the HTL play an important role in determining the performance of the single-crystal PeSCs. |
