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Heterojunction nanohybrids based on low-dimension semiconductors, including colloidal quantum dots (QDs) and 2D atomic materials (graphene, transition metal chalcogenides, etc) provide a fascinating platform to design of new photonic and optoelectronic devices that take advantages of the enhanced light-solid interaction attributed to their strong quantum confinement and superior charge mobility for uncooled photodetectors with a high gain up to 1010. In these heterojunction nanohybrids, the van der Waals (vdW) interface plays a critical role in controlling the optoelectronic process including exciton dissociation by the interface built-in field that drives the follow-up charge injection and transport to graphene. In this paper, we present our recent progress in development of such heterostructures nanohybrids for uncooled infrared detectors including PbS and FeS2 QDs/graphene and 2D vdW heterostructures MoTe2/Graphene/SnS2 and GaTe/InSe. We have found that nonstoichiometric Fe1–xS2 QDs (x = 0.01–0.107) with strong localized surface plasmonic resonance (LSPR) can have much enhanced absorption in broadband from ultraviolet to short-wave infrared (SWIR, 1–3 μm). Consequently, the LSPR Fe1–xS2 QDs/graphene heterostructure photodetectors exhibit extraordinary photoresponsivity in exceeding 4.32 ×106 A/W and figure-of-merit detectivity D* < 7.50 ×1012 Jones in the broadband of UV–Vis–SWIR at room temperature. The 2D vdW heterostructures allows novel designs of interface band alignments with uncooled NIR-SWIR D* up to 1012 Jones. These results illustrate that the heterostructure nanohybrids provide a promising pathway for low-cost, printable and flexible infrared detectors and imaging systems.
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This content will become publicly available on December 4, 2026
Van der Waals heterostructures: a promising platform to design high-performance optoelectronics
Abstract Two-dimensional (2D) atomic materials regard a large family of monolayer or few layers atomic sheets that can stand alone. While there are no dangling chemical bonds in the direction normal to the sheets, stacking different kinds of 2D atomic materials into so-called van der Waals (vdW) heterostructures enables a platform for designing high-performance quantum devices that can have unique and unprecedented physical properties and device functionalities in conventional semiconductors. Following the discovery of the first 2D atomic material of graphene in 2004, the progress in exploration of new 2D atomic materials and their vdW heterostructures has been explosive during the past two decades. This perspective aims to highlight some recent progress in the research of vdW heterostructures, particularly in transition-metal dichalcogenide/graphene optoelectronics, enabled by the quantum physics in constituent components and their interfaces. New approaches in layer by layer synthesizing these vdW heterostructures are promising for wafer-size fabrication of high-performance, low-cost optoelectronic devices for practical applications.
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- Award ID(s):
- 2412221
- PAR ID:
- 10683558
- Publisher / Repository:
- IOP
- Date Published:
- Journal Name:
- Nano Futures
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2399-1984
- Page Range / eLocation ID:
- 042504
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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