Enhanced crystallization of solution-processed perovskite using urea as an additive for large-grain MAPbIperovskite solar cells.

Perovskite crystal quality plays an important role in perovskite solar cells, given that multiple grain boundaries and trap states in the perovskite films hamper further enhancement of solar cell efficiency. Using the solution method to prepare perovskite films with large grains and high coverage requires further improvements. Herein, we introduce Lewis base urea as an additive into the precursor of perovskite to control the crystallization dynamics, allowing for large-grain crystal growth.

A sandwich-like electron transport layer to assist highly efficient planar perovskite solar cells.

Co-modification of an electron transport layer (ETL) with metal oxides and organic molecules can optimize the structure of the ETL and improve the performance of perovskite solar cells (PSCs). Here, a sandwich-structured ETL consisting of MgO/SnO2/EA was designed by co-modifying a SnO2 ETL with magnesium oxide (MgO) and ethanolamine (EA). The device with an ETL modified with MgO and EA has excellent performance in enhancing electron transport and blocking holes.