H-BN-Encapsulated Uncooled Infrared Photodetectors Based on Tantalum Nickel Selenide

Uncooled broadband spectrum detection, spanning from visible to mid-wave-infrared regions, offers immense potential for applications in environmental monitoring, optical telecommunications, and radar systems. While leveraging proven technologies, conventional mid-wave-infrared photodetectors are encumbered by high dark currents and the necessity for cryogenic cooling. Correspondingly, innovative low-dimensional materials like black phosphorus manifest weak photoresponse and instability. Here, tantalum nickel selenide (Ta₂NiSe₅) infrared photodetectors with an operational wavelength range from 520 nm to 4.6 µm, utilizing a hexagonal boron nitride (h-BN) encapsulation technique are introduced. The h-BN encapsulated metal-Ta₂NiSe₅-metal photodetector demonstrates a responsivity of 0.86 A W⁻¹, a noise equivalent power of 1.8 × 10⁻¹¹ W Hz^−1/2, and a peak detectivity of 8.75 × 10⁸ cm Hz^1/2 W⁻¹ at 4.6 µm under ambient conditions. Multifaceted mechanisms of photocurrent generation in the novel device prototype subject are scrutinized to varying wavelengths of radiation, by characterizing the temporal-, bias-, power-, and temperature-dependent photoresponse. Moreover, the photopolarization dependence is delved and concealed-target imaging is demonstrated, which exhibits polarization angle sensitivity and high-fidelity imaging across the visible, short-wave, and mid-wave-infrared bands. The observations, which reveal versatile detection modalities, propose Ta₂NiSe₅ as a promising low-dimensional material for advanced applications in nano-optoelectronic device.     

Direct Polarimetric Image Sensor and Wide Spectral Response Based on Quasi-1D Sb2S3 Nanowire

Polarized photodetectors with wide spectral detection and ultra-fast photoresponses based on anisotropic semiconductors have potential applications in military and civilian fields and have been widely studied in recent years. The dual advantages of low-symmetry crystal structure and special electronic band-structure make Sb₂S₃ the perfect choice for polarized photodetection. In this work, the optical, vibrational, and optoelectronic anisotropy of the high-quality orthorhombic Sb₂S₃ nanowires are systematically investigated by experimental and theoretical studies. The metal-semiconductor-metal photodetectors based on a single Sb₂S₃ nanowire exhibit good polarization sensitivity in a broadband range from ultraviolet to near-infrared (360 to 1550 nm) and the obtained maximum dichroic ratio is 2.54 at 638 nm. The polarization-sensitive photocurrent mapping results show that the photocurrent is mainly derived from the Schottky junction at the interface between Au and Sb₂S₃. The effective separation of the photo-generated carriers near the Schottky junction gives a photodetector response time of 470 µs. The direct polarimetric imaging demonstrates that the gray value of the image obtained by the imaging system is sensitive to the object's polarized direction. This natural sensitivity of the Sb₂S₃-based photodetector to polarized objects makes it possible to image polarized objects directly as an image sensor.     

Photoexcited Ultraviolet-to-Infrared (II) Pyroelectricity in a 2D Ferroelectric Perovskite Driving Broadband Self-Powered Photoactivities

Photoexcited pyroelectricity in ferroelectrics allows the direct conversion of light radiation into electric signal without external power source, thus paving an avenue to promote optoelectronic device performances. However, it is urgently demanded to exploit new ferroelectrics with this attribute covering ultraviolet (UV)-to-infrared (IR) region for self-powered photodetection. Herein, broadband light-induced pyroelectric effects in a new 2D perovskite-type ferroelectric, (BBA)2(EA)2Pb3Br10 (1; BBA = p-bromobenzylammonium, EA = ethylammonium), showing a high Curie temperature of 425 K and notable pyroelectric coefficient (≈5.4 × 10⁻³ µC cm⁻² K⁻¹) is presented. Especially, photo-induced change of its electric polarization leads to ultraviolet-to-infrared pyroelectricity in a wide spectral region (377–1950 nm). Broadband photoactivities actualized by this property break the limitation of its optical bandgap. Thus, single-crystal detectors of 1 are sensitive to UV-to-IR light with a small temperature fluctuation of 0.3 K, exhibiting a high transient responsivity up to ≈0.28 mA W⁻¹ and specific detectivity of 1.31 × 10¹⁰ Jones under zero bias (at 405 nm); such figure-of-merits are beyond than those self-powered photodetectors using oxide ferroelectrics. It is anticipated that the findings of light-induced pyroelectricity afford a feasible strategy to assemble newly-conceptual smart photoelectric devices, such as self-powered broadband detectors.     

High Performance Ternary Organic Phototransistors with Photoresponse up to 2600 nm at Room Temperature

Infrared (IR) photodetection is important for light communications, military, agriculture, and related fields. Organic transistors are investigated as photodetectors. However, due to their large band gap, most organic transistors can only respond to ultraviolet and visible light. Here high performance IR phototransistors with ternary semiconductors of organic donor/acceptor complex and semiconducting single-walled carbon nanotubes (SWCNTs), without deep cooling requirements are developed. Due to both the ultralow intermolecular electronic transition energy of the complex and charge transport properties of SWCNTs, the phototransistor realizes broadband photodetection with photoresponse up to 2600 nm. Moreover, it exhibits outstanding performance under 2000 nm light with photoresponsivity of 2.75 × 10⁶ A W⁻¹, detectivity of 3.12 × 10¹⁴ Jones, external quantum efficiency over 10⁸%, and high I_photo/I_dark ratio of 6.8 × 10⁵. The device exhibits decent photoresponse to IR light even under ultra-weak light intensity of 100 nW cm⁻². The response of the phototransistor to blackbody irradiation is demonstrated, which is rarely reported for organic phototransistors. Interestingly, under visible light, the device can also be employed as synaptic devices, and important basic functions are realized. This strategy provides a new guide for developing high performance IR optoelectronics based on organic transistors.     

High-Performance Near-Infrared Photodetectors Based on Surface-Doped InSe

2D InSe is one of the semimetal chalcogenides that has been recently given attention thanks to its excellent electrical properties, such as high mobility near 1000 cm² V⁻¹ s⁻¹ and moderate band gap of ≈1.26 eV suitable for IR detection. Here, high-performance visible to near-infrared (470–980 nm wavelength (λ)) photodetectors using surface-doped InSe as a channel and few-layer graphenes (FLG) as electrodes are reported, where the InSe top region is relatively p-doped using AuCl₃. The surface-doped InSe photodetectors show outstanding performance, achieving a photoresponsivity (R) of ≈19 300 A W⁻¹ and a detectivity (D*) of ≈3 × 10¹³ Jones at λ = 470 nm, and R of ≈7870 A W⁻¹ and D* of ≈1.5 × 10¹³ Jones at λ = 980 nm, superior to previously reported 2D material-based IR photodetectors operating without an applied gate bias. Surface doping using AuCl₃ renders a band bending at the junction between the InSe surface and the top FLG contact, which facilitates electron-hole pair separation and immediate photodetection. Multiple doped or undoped InSe photodetectors with different device structures are investigated, providing insight into the photodetection mechanism and optimizing performance. Encapsulation with hexagonal boron nitride dielectric also allows for 3-month stability.     

All-Dielectric Nanostructure Fabry–Pérot-Enhanced Mie Resonances Coupled with Photogain Modulation toward Ultrasensitive In2S3 Photodetector

As the fresh blood of 2D family, non-layered 2D materials (2DNLMs) have demonstrated great potential in the application of next-generation optoelectronic devices. However, stemming from the weak light absorption brought by atomically thin thickness and the interfacial recombination brought by surface dangling bonds, traditional 2DNLM photodetectors are always accompanied by limited performance. Herein, a structure that integrates Si nanopillar array and non-layered 2D In₂S₃ to construct an ultrasensitive photodetector is designed. In particular, periodically Si nanopillars can act as Fabry–Pérot-enhanced Mie resonators that can effectively control and enhance the light absorption of 2D In₂S₃. On the other hand, a vertical built-in electric field is introduced in the In₂S₃ channel to capture photogenerated holes and leave electrons recycling in In₂S₃, obtaining a high photogain. Benefiting from these two mechanisms, this proposed photodetector presents a high responsivity of 4812 A W⁻¹ and short rise/decay time of 5.2/4.0 ms at the wavelength of 405 nm. Especially, a high light on–off ratio greater than 10⁶ and a record-high detectivity of 5.4 × 10¹⁵ Jones are achieved, representing one of the most sensitive photodetectors based on 2D materials. This deliberate device design concept suggests an effective scheme to construct high-performance 2DNLM optoelectronic devices.     

Highly Sensitive Low‐Bandgap Perovskite Photodetectors with Response from Ultraviolet to the Near‐Infrared Region

It is a great challenge to obtain broadband response perovskite photodetectors (PPDs) due to the relatively large bandgaps of the most used methylammonium lead halide perovskites. The response range of the reported PPDs is limited in the ultraviolet–visible range. Here, highly sensitive PPDs are successfully fabricated with low bandgap (≈1.25 eV) (FASnI₃)_0.6(MAPbI₃)_0.4 perovskite as active layers, exhibiting a broadband response from 300 to 1000 nm. The performance of the PPDs can be optimized by adjusting the thicknesses of the perovskite and C₆₀ layers. The optimized PPDs with 1000 nm thick perovskite layer and 70 nm thick C₆₀ layer exhibit an almost flat external quantum efficiency (EQE) spectrum from 350 to 900 nm with EQE larger than 65% under ?0.2 V bias. Meanwhile, the optimized PPDs also exhibit suppressed dark current of 3.9 nA, high responsivity (R ) of over 0.4 A W^?1, high specific detectivity (D* ) of over 10¹² Jones in the near‐infrared region under ?0.2 V. Such highly sensitive broadband response PPDs, which can work well as self‐powered conditions, offer great potential applications in multicolor light detection.     

Junction Field-Effect Transistors Based on PdSe2/MoS2 Heterostructures for Photodetectors Showing High Responsivity and Detectivity

2D materials have shown great promise for next-generation high-performance photodetectors. However, the performance of photodetectors based on 2D materials is generally limited by the tradeoff between photoresponsivity and photodetectivity. Here, a novel junction field-effect transistor (JFET) photodetector consisting of a PdSe₂ gate and MoS₂ channel is constructed to realize high responsivity and high detectivity through effective modulation of top junction gate and back gate. The JFET exhibits high carrier mobility of 213 cm² V⁻¹ s⁻¹. What is more, the high responsivity of 6 × 10² A W⁻¹, as well as the high detectivity of 10¹¹ Jones, are achieved simultaneously through the dual-gate modulation. The high performance is attributed to the modulation of the depletion region by the dual-gate, which can effectively suppress the dark current and enhance the photocurrent, thereby realizing high detectivity and responsivity. The JFET photodetector provides a new approach to realize photodetectors with high responsivity and detectivity.     

High-Performance van der Waals Metal-Insulator-Semiconductor Photodetector Optimized with Valence Band Matching

The vertical metal-insulator-semiconductor (MIS) photodetectors based on van der Waals heterostructures (vdWHs), fabricated by rationally stacking different layers without the limit of lattice-match, have attracted broad interest due to their wide wavelength monitoring range, high responsivity, high detectivity, and fast response. Here, for the first time, the control of barrier height in vdWHs MIS photodetectors is systematically investigated. Optimizing semiconducting and insulating layers enables lowering the hole barrier height to achieve a high performance of the device. Graphene/hexagonal boron nitride (h-BN)/SnS₂ device shows the best photodetection performance compared to the other common 2D semiconductors. The lowest barrier height ensures that the photo-induced holes transfer efficiently to the graphene electrode and the dark current is highly suppressed by the h-BN layers. Consequently, the graphene/h-BN/SnS₂ MIS photodetectors have a high photoresponsivity of 2 A W⁻¹, a high detectivity of 10¹³ Jones, and a photocurrent/dark current ratio of 5.2 × 10⁵ at a low applied bias of −0.6 V. The highest detectivity reaches 9.6 × 10¹³ Jones which is 100–1000 times greater than previously reported vdWHs MIS photodetectors.     

High‐Performance Flexible Broadband Photodetector Based on Organolead Halide Perovskite

Organolead halide perovskites have attracted extensive attentions as light harvesting materials for solar cells recently, because of its high charge‐carrier mobilities, high photoconversion efficiencies, low energy cost, ease of deposition, and so on. Herein, with CH₃NH₃PbI₃ film deposited on flexible ITO coated substrate, the first organolead halide perovskite based broadband photodetector is demonstrated. The organolead halide perovskite photodetector is sensitive to a broadband wavelength from the ultraviolet light to entire visible light, showing a photo‐responsivity of 3.49 A W^?1, 0.0367 A W^?1, an external quantum efficiency of 1.19×10³%, 5.84% at 365 nm and 780 nm with a voltage bias of 3 V, respectively. Additionally, the as‐fabricated photodetector exhibit excellent flexibility and robustness with no obvious variation of photocurrent after bending for several times. The organolead halide perovskite photodetector with high sensitivity, high speed and broad spectrum photoresponse is promising for further practical applications. And this platform creates new opportunities for the development of low‐cost, solution‐processed and high‐efficiency photodetectors.     

Ultrahigh Stability 3D TI Bi2Se3/MoO3 Thin Film Heterojunction Infrared Photodetector at Optical Communication Waveband

Infrared (IR) detection at 1300–1650 nm (optical communication waveband) is of great significance due to its wide range of applications in commerce and military. Three dimensional (3D) topological insulator (TI) Bi₂Se₃ is considered a promising candidate toward high‐performance IR applications. Nevertheless, the IR devices based on Bi₂Se₃ thin films are rarely reported. Here, a 3D TI Bi₂Se₃/MoO₃ thin film heterojunction photodetector is shown that possesses ultrahigh responsivity (R_i), external quantum efficiency (EQE), and detectivity (D*) in the broadband spectrum (405–1550 nm). The highest on–off ratio of the optimized device can reach up to 5.32 × 10⁴. R_i, D*, and the EQE can reach 1.6 × 10⁴ A W^?1, 5.79 × 10¹¹ cm² Hz^1/2 W^?1, and 4.9 × 10⁴% (@ 405 nm), respectively. Surprisingly, the R_i can achieve 2.61 × 10³ A W^?1 at an optical communication wavelength (@ 1310 nm) with a fast response time (63 µs), which is two orders of magnitude faster than that of other TIs‐based devices. In addition, the device demonstrates brilliant long‐term (>100 days) environmental stability under environmental conditions without any protective measures. Excellent device photoelectric properties illustrate that the 3D TI/inorganic heterojunction is an appropriate way for manufacturing high‐performance photodetectors in the optical communication, military, and imaging fields.     

Highly nonlinear and highly birefringent dispersion compensating photonic crystal fiber

This paper presents an optimum design for highly birefringent hybrid photonic crystal fiber (HyPCF) based on a modified structure for broadband compensation covering the S, C, and L-communication bands i.e. wavelength ranging from 1460 to 1625 nm. The finite element method (FEM) with perfectly matched layer (PML) circular boundary is used to investigate the guiding property. It is demonstrated that it is possible to obtain broadband large negative dispersion, and dispersion coefficient varies from −388.72 to −723.1 ps nm⁻¹ km⁻¹ over S, C and L-bands with relative dispersion slope (RDS) matched to that of single mode fiber (SMF) of about 0.0036 nm⁻¹ at 1550 nm. According to simulation, a five-ring dispersion compensating hybrid cladding photonic crystal fiber (DC-HyPCF) is designed that simultaneously offers birefringence of order 3.79 × 10⁻², nonlinear coefficient of 40.1 W⁻¹ km⁻¹ at 1550 nm wavelength. In addition to this, effective area, residual dispersion, and confinement loss of the proposed DC-HyPCF are also reported and discussed.     

Single-Orientation Epitaxy of Quasi-1D Tellurium Nanowires on M-Plane Sapphire for Highly Uniform Polarization Sensitive Short-Wave Infrared Photodetection

Tellurium (Te), an elemental van der Waals semiconductor, has intriguing anisotropic physical properties owing to its inherent quais-1D crystal structure. Synthesizing ultrathin Te crystal with uniform orientation is important to its large-scale device applications, but that remains a great challenge. Herein, the nanoscale grooves-induced unidirectional epitaxy growth of 1D Te nanowires via physical vapor deposition on the annealed m-plane sapphire is demonstrated. By enhancing the annealing temperature from 1000 to 1300 °C, nanoscale grooves on m-plane sapphire arising along the [10$\overline{1}$0] direction and gradually distinct, and the corresponding Te nanowires grown on them turns from random to uniform, finally achieving nearly 95% unidirectional Te nanowires. The as-grown Te nanowires possess high crystallinity with clearly chiral helical chains along the c-axis direction and reveal thickness-tunable bandgap with prominent linear-dichroic. As results, the Te nanowire-based photodetectors demonstrate a broadband photoresponse from visible (532 nm) to short-wave infrared (2530 nm), with high responsivity of 327 A W⁻¹ as well as strong and uniform polarization sensitivity (anisotropic ratio = 2.05) to 1550 nm light. The high crystallinity and superior anisotropy of Te nanowires, combined with the orientation-controlled preparation endows it with great feasibility for constructing chip-scale multifunctional optoelectronic devices.     

Machine Vision Based on an Ultra-Wide Bandgap 2D Semiconductor AsSbO3

Facing the future development trend of miniaturization and intelligence of electronic devices, solar-blind photodetectors based on ultrawide-bandgap 2D semiconductors have the advantages of low dark current, and high signal-to-noise ratio, as well as the features of micro-nanometer miniaturization and multi-functionalization of 2D material devices, which have potential applications in the photoelectric sensor part of high-performance machine vision systems. This study reports a 2D oxide semiconductor, AsSbO₃, with an ultrawide bandgap (4.997 eV for monolayer and 4.4 eV for multilayer) to be used to fabricate highly selective solar-blind UV photodetectors, of which the dark current as low as 100 fA and rejection ratio of UV-C and UV-A reaches 7.6 × 10³. Under 239 nm incident light, the responsivity is 105 mA W⁻¹ and the detectivity is 7.58 × 10¹² Jones. Owing to the remarkable anisotropic crystal structure, AsSbO₃ also shows significant linear dichroism and nonlinear optical properties. Finally, a simple machine vision system is simulated by combining the real-time imaging function in solar-blind UV with a convolutional neural network. This study enriches the material system of ultrawide-bandgap 2D semiconductors and provides insight into the future development of high-performance solar-blind UV optoelectronic devices.     

3D Visible-Light-Driven Plasmonic Oxide Frameworks Deviated from Liquid Metal Nanodroplets

Eutectic gallium-indium (EGaIn) liquid metal droplets have been considered as a suitable platform for producing customized 3D composites with functional nanomaterials owing to their soft and highly reductive surface. Herein, the synthesis of a 3D plasmonic oxide framework (POF) is reported by incorporating the ultra-thin angstrom-scale-porous hexagonal molybdenum oxide (h-MoO₃) onto the spherical EGaIn nanodroplets through ultrasonication. Simultaneously, a large number of oxygen vacancies form in h-MoO₃, boosting its free charge carrier concentration and therefore generating a broad surface plasmon resonance across the whole visible light spectrum. The plasmonic chemical sensing properties of the POF is investigated by the surface-enhanced Raman scattering detection of rhodamine 6G (R6G) at 532 nm, in which the minimum detectable concentration is 10⁻⁸ m and the enhancement factor reached up to 6.14 × 10⁶. The extended optical absorption of the POF also allowed the efficient degradation of the R6G dye under the excitation of ultraviolet-filtered simulated solar light. Furthermore, the POF exhibits remarkable photocurrent responses towards the entire visible light region with the maximum response of ≈ 1588 A W⁻¹ at 455 nm. This work demonstrates the great potential of the liquid metal-based POFs for high-performance sensing, catalytic, and optoelectronic devices.     

Flexible High-Performance Photovoltaic Devices based on 2D MoS2 Diodes with Geometrically Asymmetric Contact Areas

Optoelectronic performance of 2D transition metal dichalcogenides (TMDs)-based solar cells and self-powered photodetectors remain limited due to fabrication challenges, such as difficulty in doping TMDs to form p–n junctions. Herein, MoS₂ diodes based on geometrically asymmetric contact areas are shown to achieve a high current rectification ratio of ≈10⁵, facilitating efficient photovoltaic charge collection. Under solar illumination, the device demonstrates a high open-circuit voltage (V_oc) of 430 mV and a short-circuit current density (J_sc) of −13.42 mA cm⁻², resulting in a high photovoltaic power conversion efficiency (PCE) of 3.16%, the highest reported for a lateral 2D solar cell. The diodes also show a high photoresponsivity of 490.3 mA W⁻¹, and a large photo detectivity of 4.05 × 10¹⁰ Jones, along with a fast response time of 0.8 ms under 450 nm wavelength at zero bias for self-powered photodetection applications. The device transferred on a flexible substrate shows a high photocurrent and PCE retentions of 94.4%, and 88.2% after 5000 bending cycles at a bending radius of 1.5 cm, respectively, demonstrating robustness for flexible optoelectronic applications. The simple fabrication process, superior photovoltaic properties, and high flexibility suggests that the geometrically asymmetric MoS₂ device architecture is an excellent candidate for flexible photovoltaic and optoelectronic applications.     

Solution‐Processed Flexible Broadband Photodetectors with Solution‐Processed Transparent Polymeric Electrode

Room‐temperature solution‐processed flexible photodetectors with spectral response from 300 to 2600 nm are reported. Solution‐processed polymeric thin film with transparency ranging from 300 to 7000 nm and superior electrical conductivity as the transparent electrode is reported. Solution‐processed flexible broadband photodetectors with a “vertical” device structure incorporating a perovskite/PbSe quantum dot bilayer thin film based on the above solution‐processed transparent polymeric electrode are demonstrated. The utilization of perovskite/PbSe quantum dot bilayer thin film as the photoactive layer extends spectral response to infrared region and boosts photocurrent densities in both visible and infrared regions through the trap‐assisted photomultiplication effect. Operated at room temperature and under an external bias of ‐1 V, the solution‐processed flexible photodetectors exhibit over 230 mA W^‐1 responsivity, over 1011 cm Hz1/2/W photodetectivity from 300 to 2600 nm and ≈70 dB linear dynamic ranges. It is also found that the solution‐processed flexible broadband photodetectors exhibit fast response time and excellent flexibility. All these results demonstrate that this work develop a facile approach to realize room‐temperature operated ultrasensitive solution‐processed flexible broadband photodetectors with “vertical” device structure through solution‐processed transparent polymeric electrode.     

Organic photodetector with built-in amplification for the detection of visible light with low optical power

We report on an organic-based photodetector that integrates a dual-gate organic thin-film transistor (DG-OTFT) with an organic photodiode (OPD) to produce a device with a high effective responsivity at low optical power and video-rate compatible response. In this device, the OPD operates in photovoltaic mode, instead of the commonly used photoconductive mode, to modulate one of the gate voltages of the DG-OTFT. Effective responsivity values of 10 A W⁻¹ are measured at optical power values lower than 10 nW at 635 nm. Modeling of the operation of this new photodetector suggests that effective responsivity values up to 10⁵ A W⁻¹ can be achieved at optical powers of 1 nW using current printing technology and state-of-the-art organic semiconductors.     

Double-Side Crystallization Tuning to Achieve over 1 µm Thick and Well-Aligned Block-Like Narrow-Bandgap Perovskites for High-Efficiency Near-Infrared Photodetectors

Solution-processed narrow-bandgap Sn–Pb perovskites have shown their potential in near-infrared (NIR) photodetection as a promising alternative to traditional silicon and inorganic compounds. To achieve efficient NIR photodetection, high-quality Sn–Pb perovskite thick films with well-packed, smooth, and pinhole/void-free features are highly desirable for boosting the spectral absorption. Understanding the crystallization kinetics and tuning the crystallization are fundamentally important to reach such high-quality thick Sn–Pb perovskite films, and have been limitedly explored. Herein, an approach of double-side crystallization tuning through low-temperature space-restricted annealing in methylammonium-free Sn–Pb perovskite films with over 1 µm thickness is proposed. More specifically, through simultaneously retarding the crystallization in the top of precursor films and promoting the crystal growth of the bottom of precursor films, high-quality and block-like thick FA_0.85Cs_0.15Sn_0.5Pb_0.5I₃ perovskite films with improved crystallinity, preferred out-of-plane orientation, and reduced trap density are achieved. Finally, photovoltaic-mode Sn–Pb perovskite NIR photodetectors show a high external quantum efficiency of ≈80% at 760–900 nm, a recorded responsivity of 0.53 A W⁻¹, and a high specific detectivity of 6 × 10¹² Jones at 940 nm. This study offers the fundamental understanding of the crystallization kinetics of thick perovskite films and paves the way for perovskite-based emerging NIR photodetection and imaging applications.     

Broadband Bi2O2Se Photodetectors from Infrared to Terahertz

2D Bi₂O₂Se has shown great potential in photodetector from visible to infrared (IR) owing to its high mobility, ambient stability, and layer-tunable bandgaps. However, for the terahertz (THz) band with longer wavelength and richer spectral information, there are few reports on the research of THz detection based on 2D materials. Herein, an antenna-assisted Bi₂O₂Se photodetector is constructed to achieve broadband photodetection from IR to THz ranges driven by multi-mechanism of electromagnetic waves to electrical conversion. The good tradeoff between the bandgap and high mobility results in a broad spectral detection. In the IR region, the nonequilibrium carriers result from photo-induced electron-hole pairs in the Bi₂O₂Se body. While in the THz region, the carriers are caused by the injected electrons from the metal electrodes by the electromagnetic-induced well. The Bi₂O₂Se photodetector achieves a broadband responsivity of 58 A W^-1 at 1550 nm, 2.7 × 10⁴ V W^-1 at 0.17 THz, and 1.9 × 10⁸ V W^-1 at 0.029 THz, respectively. Surprisingly, an ultrafast response time of 476 ns and a quite low noise equivalent power of 0.2 pW Hz^−1/2 are acquired at room temperature. Our researches exhibit promising prospects of Bi₂O₂Se in broadband detection, THz imaging, and ultrafast sensing.