Supramolecular engineering of charge transfer in wide bandgap organic semiconductors with enhanced visible-to-NIR photoresponse

• Published in: Nature communications Vol. 12; no. 1; p. 3667
• Main Authors: Yao, Yifan, Ou, Qi, Wang, Kuidong, Peng, Haijun, Fang, Feier, Shi, Yumeng, Wang, Ye, Asperilla, Daniel Iglesias, Shuai, Zhigang, Samorì, Paolo
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 16.06.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 142/126; 639/301/1005/1007; 639/301/923/966; 639/624/399/1028; 639/925/357/995; Charge transfer; Chemical Sciences; Computer architecture; Electromagnetic absorption; Electronics industry; Gold; Graphene; Humanities and Social Sciences; I.R. radiation; Material chemistry; multidisciplinary; Nanotechnology; Nanowires; Near infrared radiation; Optoelectronic devices; Organic semiconductors; Photoelectricity; Photonic band gaps; Photoresponse; Phototransistors; Science; Science (multidisciplinary); Self-assembly
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-23914-2

Organic photodetectors displaying efficient photoelectric response in the near-infrared are typically based on narrow bandgap active materials. Unfortunately, the latter require complex molecular design to ensure sufficient light absorption in the near-infrared region. Here, we show a method combining an unconventional device architecture and ad-hoc supramolecular self-assembly to trigger the emergence of opto-electronic properties yielding to remarkably high near-infrared response using a wide bandgap material as active component. Our optimized vertical phototransistors comprising a network of supramolecular nanowires of N,N′-dioctyl-3,4,9,10-perylenedicarboximide sandwiched between a monolayer graphene bottom-contact and Au nanomesh scaffold top-electrode exhibit ultrasensitive light response to monochromatic light from visible to near-infrared range, with photoresponsivity of 2 × 10 5 A/W and 1 × 10 2 A/W, at 570 nm and 940 nm, respectively, hence outperforming devices based on narrow bandgap materials. Moreover, these devices also operate as highly sensitive photoplethysmography tool for health monitoring. Despite advances in designed supramolecular organic nanowires for optoelectronics, realizing near infrared phototransistors with wide bandgap materials remains a challenge. Here, the authors report high-performance vertical phototransistors featuring supramolecularly engineered organic nanowires.