Highly sensitive multicolor uncooled photoresponse and imaging based on symmetry breaking heterojunction

Abstract

Multicolor photodetection, essential for applications in infrared imaging, environmental monitoring, and spectral analysis, is often limited by the narrow bandgaps of conventional materials, which struggle with speed, sensitivity, and room-temperature operation. We address these issues with a multicolor uncooled photodetector based on an asymmetric Au/SnS/Gr vertical heterojunction with inversion-symmetry breaking. This design utilizes the complementary bandgaps of SnS and graphene to enhance the efficiency of carriers' transport through consistently oriented built-in electric fields, achieving significant advancements in directional photoresponse. The device demonstrates highly sensitive photoelectric detection performance, such as a responsivity (R) of 55.4–89.7 A W^–1 with rapid response times of approximately 104 μs, and exceptional detectivity (D*) of 2.38 × 10¹⁰ Jones ~8.19 × 10¹³ Jones from visible (520 nm) to infrared (2000 nm) light, making it suitable for applications demanding an imaging resolution of ~0.5 mm. Additionally, the comparative analysis reveals that the asymmetric vertical heterojunction outperforms its counterparts, exhibiting approximately 9-fold the photoresponse of symmetric vertical heterojunction and almost 100-fold that of symmetric horizontal heterojunction. This highly sensitive multicolor detector holds significant promise for applications in advanced versatile object detection and imaging recognition systems.

Keywords

heterojunction / highly sensitive photoresponse / imaging / inversion-symmetry breaking / multicolor uncooled detector

References

[1] Ding N, Wu Y, Xu W, et al. A novel approach for designing efficient broadband photodetectors expanding from deep ultraviolet to near infrared. Light Sci Appl. 2022; 11(1): 91.

[2] Liu CH, Chang YC, Norris TB, Zhong Z. Graphene photodetectors with ultra-broadband and high responsivity at room temperature. Nat Nanotechnol. 2014; 9(4): 273-278.

[3] Kenry DY, Liu B. Recent advances of optical imaging in the second near-infrared window. Adv Mater. 2018; 30(47): 1802394.

[4] Chen Y, Ma W, Tan C, et al. Broadband Bi₂O₂Se photodetectors from infrared to terahertz. Adv Funct Mater. 2021; 31(14): 2009554.

[5] Rogalski A. Progress in focal plane array technologies. Prog Quantum Electron. 2012; 36(2-3): 342-473.

[6] Konstantatos G. Current status and technological prospect of photodetectors based on two-dimensional materials. Nat Commun. 2018; 9(1): 5266.

[7] Tian W, Sun H, Chen L, et al. Low-dimensional nanomaterial/Si heterostructure-based photodetectors. InfoMat. 2019; 1(2): 140-163.

[8] Guo S, Zhang D, Zhou J, et al. Enhanced infrared photoresponse induced by symmetry breaking in a hybrid structure of graphene and plasmonic nanocavities. Carbon. 2020; 170: 49-58.

[9] Alymov G, Rumyantsev V, Morozov S, Gavrilenko V, Aleshkin V, Svintsov D. Fundamental limits to far-infrared lasing in auger-suppressed HgCdTe quantum wells. ACS Photonics. 2020; 7(1): 98-104.

[10] Geim AK, Novoselov KS. The rise of graphene. Nat Mater. 2007; 6(3): 183-191.

[11] Bonaccorso F, Sun Z, Hasan T, Ferrari AC. Graphene photonics and optoelectronics. Nat Photonics. 2010; 4(9): 611-622.

[12] Steinmann V, Jaramillo R, Hartman K, et al. 3.88% efficient tin sulfide solar cells using congruent thermal evaporation. Adv Mater. 2014; 26(44): 7488-7492.

[13] Brent JR, Lewis DJ, Lorenz T, et al. Tin (II) sulfide (SnS) nanosheets by liquid-phase exfoliation of herzenbergite: IV-VI main group two-dimensional atomic crystals. J Am Chem Soc. 2015; 137(39): 12689-12696.

[14] Zhao LD, Tan G, Hao S, et al. Ultrahigh power factor and thermoelectric performance in hole-doped single-crystal SnSe. Science. 2016; 351(6269): 141-144.

[15] Rath T, Gury L, Sánchez-Molina I, Martínez L, Haque SA. Formation of porous SnS nanoplate networks from solution and their application in hybrid solar cells. Chem Commun. 2015; 51(50): 10198-10201.

[16] Burton LA, Colombara D, Abellon RD, et al. Synthesis, characterization, and electronic structure of single-crystal SnS, Sn₂S₃, and SnS₂. Chem Mater. 2013; 25(24): 4908-4916.

[17] Yu Y, Cao D, Yang L, et al. Oxidation-induced graded bandgap narrowing in two-dimensional tin sulfide for high-sensitivity broadband photodetection. J Colloid Interface Sci. 2024; 679(Pt A): 430-440.

[18] Zhou X, Gan L, Zhang Q, et al. High performance near-infrared photodetectors based on ultrathin SnS nanobelts grown via physical vapor deposition. J Mater Chem C. 2016; 4(11): 2111-2116.

[19] Guo R, Wang X, Kuang Y, Huang B. First-principles study of anisotropic thermoelectric transport properties of IV-VI semiconductor compounds SnSe and SnS. Phys Rev B. 2015; 92(11): 115-202.

[20] Tian Z, Guo C, Zhao M, Li R, Xue J. Two-dimensional SnS: a phosphorene analogue with strong in-plane electronic anisotropy. ACS Nano. 2017; 11(2): 2219-2226.

[21] Lee YH, Park S, Won Y, et al. Flexible high-performance graphene hybrid photodetectors functionalized with gold nanostars and perovskites. NPG Asia Mater. 2020; 12(1): 79.

[22] Tong L, Su C, Li H, et al. Self-driven Gr/WSe₂/Gr photodetector with high performance based on asymmetric Schottky van der Waals contacts. ACS Appl Mater Interfaces. 2023; 15(49): 57868-57878.

[23] Zhou X, Hu X, Zhou S, et al. Tunneling diode based on WSe₂/SnS₂ heterostructure incorporating high detectivity and responsivity. Adv Mater. 2018; 30(7): 1703286.

[24] Rut’ kov EV, Afanas'eva EY, Gall NR. Graphene and graphite work function depending on layer number on Re. Diamond Relat Mater. 2020; 209: 107576.

[25] Xu J, Luo X, Lin X, et al. Approaching the robust linearity in dual-floating van der waals photodiode. Adv Funct Mater. 2023; 33: 2310811.

[26] Liu G, Li Y, Li B, et al. High-performance photodetectors based on two-dimensional tin (II) sulfide (SnS) nanoflakes. J Mater Chem C. 2018; 6(37): 10036-10041.

[27] Sajeesh TH, Jinesh KB, Rao M, Kartha CS, Vijayakumar KP. Defect levels in SnS thin films prepared using chemical spray pyrolysis. Phys Status Solidi A. 2012; 209(7): 1274-1278.

[28] Cai S, Xu X, Yang W, Chen J, Fang X. Materials and designs for wearable photodetectors. Adv Mater. 2019; 31(18): e1808138.

[29] Nawaz MZ, Liu X, Zhou X, et al. High-performance and broadband flexible photodetectors employing multicomponent alloyed 1D CdS_xSe_1-x micro-nanostructures. ACS Appl Mater Interfaces. 2022; 14(17): 19659-19671.

[30] Kang Z, Cheng Y, Zheng Z, et al. MoS₂-based photodetectors powered by asymmetric contact structure with large work function difference. Nano-Micro Lett. 2019; 11(1): 34.

[31] Zeng L, Lin S, Lou Z, et al. Ultrafast and sensitive photodetector based on a PtSe₂/silicon nanowire array heterojunction with a multiband spectral response from 200 to 1550 nm. NPG Asia Mater. 2018; 10(4): 352-362.

[32] Li C, Wang H, Wang F, et al. Ultrafast and broadband photodetectors based on a perovskite/organic bulk heterojunction for large-dynamic-range imaging. Light Sci Appl. 2020; 9(1): 31.

RIGHTS & PERMISSIONS

2025 The Author(s). InfoMat published by UESTC and John Wiley & Sons Australia, Ltd.