High-Performance Layered Perovskite Transistors and Phototransistors by Binary Solvent Engineering
Huihui Zhu, Ao Liu, Hyunjun Kim, Jisu Hong, Ji‐Young Go, Yong‐Young Noh
Abstract
Perovskite materials have displayed remarkable performance when used in photovoltaic devices. In comparison, research on their application in thin-film transistors (TFTs) has been developing slowly. We report reliable high-performance p-channel lead-free layered perovskite phenethylammonium tin iodide TFTs using simple and easily repeatable one-step spin-coating with premixed binary solvents of N,N-dimethylformamide (DMF) and chlorobenzene (CB)/ethyl acetate (EA). CB/EA antisolvent addition facilitates nucleation and formation of films with oriented grain ripening and full coverage. The champion perovskite TFT shows a fivefold increase in the mobility (3.8 cm2 V–1 s–1) and a twofold magnitude increase in the current on/off ratio (∼106) with improved bias stress stability. Using well-developed n-channel indium gallium zinc oxide TFTs, a complementary inverter with a high gain of ∼30 is demonstrated. Moreover, with efficient charge transport, transistor amplification function, and pronounced photogating properties, the optimized perovskite phototransistors show a remarkably high photodetectivity of up to 3.2 × 1017 Jones. This simple and highly repeatable method has attracted more attention for fabricating printed high-performance perovskite TFTs and phototransistors beyond energy sector applications.