Polymer: Non-fullerene acceptor heterojunction-based phototransistor for short-wave infrared photodetection  

作　　者：Jing Li Weigang Zhu Yang Han Yanhou Geng Wenping Hu 

机构地区：[1]Key Laboratory of Organic Integrated Circuits of Ministry of Education&Key Laboratory of Molecular Optoelectronic Sciences,School of Science&Collaborative Innovation Center of Chemical Science and Engineering(Tianjin),Tianjin University,Tianjin 300072,China [2]Key Laboratory of Organic Integrated Circuits of Ministry of Education&Key Laboratory of Molecular Optoelectronic Sciences,School of Materials Science and Engineering,Tianjin University,Tianjin 300072,China

出　　处：《Nano Research》2024年第4期3087-3095,共9页纳米研究（英文版）

基　　金：supported by the Ministry of Science and Technology of China(Nos.2017YFA0204503 and 2018YFA0703200);the National Natural Science Foundation of China(Nos.52121002,51733004,51725304,21875158,and U21A6002);Tianjin Natural Science Foundation(No.20JCJQJC00300);the Discretionary Fund of Tianjin University(No.2104).

摘　　要：It remains full of challenge for extending short-wave infrared(SWIR)spectral response and weak-light detection in the context of broad spectral responses for phototransistor.In this work,a novel poly(2,5-bis(4-hexyldodecyl)-2,5-dihydro-3,6-di-2-thienyl-pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thiophene)(PDPPT3-HDO):COTIC-4F organic bulk-heterojunction is prepared as active layer for bulk heterojunction phototransistors.PDPPT3-HDO serves as a hole transport material,while COTIC-4F enhances the absorption of SWIR light to 1020 nm.As a result,smooth and connected PDPPT3-HDO film is fabricated by blade coating method and exhibits high hole mobility up to 2.34 cm^(2)·V^(-1)·s^(-1) with a current on/off ratio of 4.72×10^(5) in organic thin film transistors.PDPPT3-HDO:COTIC-4F heterojunction phototransistors exhibit high responsivity of 2680 A·W^(-1) to 900 nm and 815 A·W^(-1) to 1020 nm,with fast response time(rise time~20 ms and fall time~100 ms).The photosensitivity of the heterojunction phototransistor improves as the mass ratio of non-fullerene acceptors increases,resulting in an approximately two orders of magnitude enhancement compared to the bare polymer phototransistor.Importantly,the phototransistor exhibits decent responsivity even under ultra-weak light power of 43μW·cm^(-2) to 1020 nm.This work represents a highly effective and general strategy for fabricating efficient and sensitive SWIR light photodetectors.

关 键 词：PHOTODETECTION PHOTOTRANSISTOR organic semiconductor HETEROJUNCTION non-fullerene acceptor 

分 类 号：TN32[电子电信—物理电子学]