Two-Dimensional Dion-Jacobson Tin Perovskite Transistors with Enhanced Ambient Stability

Two-dimensional (2D) layered perovskites have garnered significant research interest within the perovskite community due to their potential as semiconducting materials characterized by high structural stability and favorable optoelectrical properties. Among various contenders, 2D Dion–Jacobson (DJ) perovskites featuring diammonium organic spacers stand out for their exceptional stability. This stability is attributed to the robust hydrogen bonding of the spacer, which leads to a shorter distance between the inorganic octahedral cage layers. In this study, we highlight the remarkable structural stability of 2D DJ perovskite in Sn2+ perovskite thin-film transistors, achieved through the incorporation of 3-(aminomethyl)piperidinium tin iodide (3AMPSnI4) and 4-(aminomethyl)piperidinium tin iodide (4AMPSnI4). The varying positions of the aminomethyl group determine the distortion of the crystal lattice, impacting their respective optical and electrical properties. The relatively low distortion 3AMPSnI4 demonstrates transistor performance with a 10-fold increase in field-effect mobility and 2 orders of magnitude improvement in the on/off current ratio through high film quality with grain size exceeding 10 μm and narrower bandgap. Moreover, the stability of both the film and device under ambient air exposure is markedly improved, with 2D DJ perovskites retaining their crystal structure for over 24 h, presenting a notable enhancement compared to 2D Ruddlesden–Popper perovskites.