Negative Phototransistors with Ultrahigh Sensitivity and Weak‐Light Detection Based on 1D/2D Molecular Crystal p–n Heterojunctions and their Application in Light Encoders

• DOI: 10.1002/adma.202201364
• Publication Date: 2022-03-24T21:34:03Z
• Authors: Xiaoting Zhu; Yujie Yan; Lingjie Sun; Yiwen Ren; Yihan Zhang; Yang Liu; Xiaotao Zhang; Rongjin Li; Huipeng Chen; Jishan Wu; Fangxu Yang; Wenping Hu
• Keywords: Crystal (programming language)

Anomalous negative phototransistors in which the channel current decreases under light illumination hold potential to generate novel and multifunctional optoelectronic applications. Although a variety of design strategies have been developed construct such devices, NPTs still suffer from far lower device performance compared well-developed positive (PPTs). In this work, 1D/2D molecular crystal p-n heterojunction, p-type 1D (1DMC) arrays are embedded into n-type 2D crystals (2DMCs), is produce ultrasensitive NPTs. The 1DMC act as light-absorbing layers induce p-doping 2DMCs through charge transfer illumination, resulting ineffective gate control significant photoresponses. As result, show remarkable performances photoresponsivity (P) (1.9 × 108 ) detectivity (D*) (1.7 1017 Jones), greatly outperforming previously reported NPTs, one highest values among all organic phototransistors. Moreover, exhibits intriguing characteristics undiscovered PPTs, including precise threshold voltage by controlling signals detection weak light. proof-of-concept, NTPs demonstrated encoders that can encrypt electrical These findings represent milestone for phototransistors, pave way development future