Addressing the Voltage Induced Instability Problem of Perovskite Semiconductor Detectors
Hsinhan Tsai, Dibyajyoti Ghosh, Wyatt Panaccione, Li‐Yun Su, Cheng‐Hung Hou, Leeyih Wang, Lei R. Cao, Sergei Tretiak, Wanyi Nie
Abstract
Perovskite-based solid-state radiation detectors have delivered impressive performances, but the electrical field induced instability has been a major detriment for the further development. Here, we identify the voltage-induced instability is directly tied to the humidity levels. A higher humidity elicits a hysteresis in the current–voltage curve and lowers the breakdown voltage. We further add a fluorinated phenylethylamine iodide (5F-PEAI) barrier layer on the perovskite, which protects the device against voltage damage. Photoluminescence maps identify the ion migration and degradation can be suppressed by 5F-PEAI. Quantum chemical simulations corroborate experimental results by revealing high energy barrier for water penetrating the 5F-PEAI layer with enhancing stability of halide perovskite under humid condition. Using a treated device, we demonstrate high X-ray sensitivities approaching 1000 μC/(Gyair·cm2) under high biases. Our work provides a mechanistic understanding on the voltage instability of 2D perovskite detectors and provides a viable solution toward robust detector development.