Senanayak Satyaprasad P, Abdi-Jalebi Mojtaba, Kamboj Varun S, Carey Remington, Shivanna Ravichandran, Tian Tian, Schweicher Guillaume, Wang Junzhan, Giesbrecht Nadja, Di Nuzzo Daniele, Beere Harvey E, Docampo Pablo, Ritchie David A, Fairen-Jimenez David, Friend Richard H, Sirringhaus Henning
Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE, UK.
CSIR- Institute of Minerals and Materials Technology Council of Scientific & Industrial Research, Bhubaneswar-751 013, Odisha, India.
Sci Adv. 2020 Apr 10;6(15):eaaz4948. doi: 10.1126/sciadv.aaz4948. eCollection 2020 Apr.
Despite sustained research, application of lead halide perovskites in field-effect transistors (FETs) has substantial concerns in terms of operational instabilities and hysteresis effects which are linked to its ionic nature. Here, we investigate the mechanism behind these instabilities and demonstrate an effective route to suppress them to realize high-performance perovskite FETs with low hysteresis, high threshold voltage stability (ΔV < 2 V over 10 hours of continuous operation), and high mobility values >1 cm/V·s at room temperature. We show that multiple cation incorporation using strain-relieving cations like Cs and cations such as Rb, which act as passivation/crystallization modifying agents, is an effective strategy for reducing vacancy concentration and ion migration in perovskite FETs. Furthermore, we demonstrate that treatment of perovskite films with positive azeotrope solvents that act as Lewis bases (acids) enables a further reduction in defect density and substantial improvement in performance and stability of n-type (p-type) perovskite devices.
尽管进行了持续的研究，但卤化铅钙钛矿在场效应晶体管（FET）中的应用在操作稳定性和滞后效应方面仍存在重大问题，这些问题与其离子性质有关。在此，我们研究了这些不稳定性背后的机制，并展示了一种有效的方法来抑制它们，以实现具有低滞后、高阈值电压稳定性（连续运行10小时内ΔV < 2 V）以及室温下迁移率值>1 cm²/V·s的高性能钙钛矿FET。我们表明，使用诸如Cs等应变缓解阳离子以及诸如Rb等充当钝化/结晶改性剂的阳离子进行多阳离子掺入，是降低钙钛矿FET中空位浓度和离子迁移的有效策略。此外，我们证明用充当路易斯碱（酸）的正共沸溶剂处理钙钛矿薄膜能够进一步降低缺陷密度，并显著提高n型（p型）钙钛矿器件的性能和稳定性。
