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 × 10⁵ A W⁻¹ and specific detectivity of 5.26 × 10¹³ Jones, which is the best performance among the reported n-type organic small molecule-based phototransistors.

在宽光谱范围内具有高载流子迁移率和有效光吸收的有机半导体是构建宽带响应有机光电探测器的最重要但最具挑战性的材料。然而，这类有机半导体，特别是空气稳定的n型有机小分子半导体的开发仍处于早期阶段。在这里，我们报告了高性能 n 型半导体晶体纳米片的制造以及在广谱范围内具有高响应的空气稳定场效应晶体管、光电晶体管的开发。基于溶剂相界面自组装方法将n型小分子半导体组装成晶体纳米片。制备了具有高电子迁移率的 N 型场效应晶体管，其电性能表现出优异的空气稳定性。令人印象深刻的是，所展示的光电晶体管在 365 至 940 nm 的宽光谱范围内表现出超高响应度，最大光响应度为 9.2 × 10⁵  A W ^-1和5.26 × 10 ¹³ Jones的比检测率，这是已报道的n型有机小分子基光电晶体管中性能最好的。