A high mobility air-stable n-type organic small molecule semiconductor with high UV–visible-to-NIR photoresponse
Ying‐Shi Guan, Jing Qiao, Yingying Liang, Hari Krishna Bisoyi, Chao Wang, Wei Xu, Daoben Zhu, Quan Li
Abstract
Abstract An organic semiconductor with high carrier mobility and efficient light absorption over a wide spectral range is of the most important yet challenging material for constructing a broadband responsive organic photodetector. However, the development of such organic semiconductors, especially for air-stable n-type organic small molecule semiconductors, is still at an early stage. Here we report the fabrication of high-performance n-type semiconducting crystalline nanosheets and the development of air-stable field-effect transistors, phototransistors, with high response over a broad spectrum. The n-type small molecule semiconductor is assembled into a crystalline nanosheet based on the solvent-phase interfacial self-assembly method. N-type field-effect transistors with high electron mobility are fabricated and their electrical performances exhibit excellent air stability. Impressively, the demonstrated phototransistors exhibit an ultrahigh responsivity over a wide spectral range from 365 to 940 nm, with a maximum photoresponsivity of 9.2 × 10 5 A W −1 and specific detectivity of 5.26 × 10 13 Jones, which is the best performance among the reported n-type organic small molecule-based phototransistors.