Fast Near‐Infrared Organic Photodetectors with Enhanced Detectivity by Molecular Engineering of Acceptor Materials DOI Creative Commons

Wentao Zhong,

Xinyuan Wang, Wei Wang

et al.

Advanced Science, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 27, 2024

Abstract Organic photodetectors (OPDs) with a near‐infrared (NIR) response beyond 900 nm are intriguing electronics for various applications. It is challenging to develop NIR OPDs high sensitivity and fast response. Herein, the acceptor materials of tuned extend detection ≈1100 improved sensitivity. A new fused ring electron acceptor, ICS (2,2'‐((2Z,2'Z)‐(((4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b:3,4‐b']dithiophene‐2,6‐diyl)bis(4‐((2‐ethylhexyl)thio)thiophene‐5,2‐diyl))bis(methaneylylidene))bis(5,6‐difluoro‐3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile), developed alkylthio thiophene as bridge, achieving small bandgap 1.35 eV while decreasing dark current densities under reverse bias. By further introducing secondary PC 61 BM, doping compensation, unfavored hole injection blocking enable improvement detectivity. The PTB7‐Th (Poly[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b;4,5‐b']dithiophene‐2,6‐diyl‐alt‐(4‐(2‐ethylhexyl)‐3‐fluorothieno[3,4‐b]thiophene‐)‐2‐carboxylate‐2‐6‐diyl]): ICS: BM deliver low density 1.23 × 10 −9 cm −2 , peak specific detectivity 1.09 13 Jones at 950 −0.2 V, speed −3 dB bandwidth 720 kHz biased V. photoplethysmography system PTB7‐Th: OPD can reliably monitor heartbeats 980 light. This study promises development organic by tuning active materials.

Language: Английский

Performance improvement of upconversion device through optimized carrier injection balance DOI
Xiaoyu Wang,

Yuanhong Hu,

Lixiang Chen

et al.

Optics Letters, Journal Year: 2025, Volume and Issue: 50(4), P. 1361 - 1361

Published: Jan. 23, 2025

Enhancing carrier injection balance in near-infrared (NIR) to visible upconversion devices (UCDs) is crucial for improving efficiency and stability. This study presents the incorporation of an insulating polymer (polymethyl methacrylate (PMMA)) between aluminum cathode electron transport layer reduce excess electrons a light-emitting layer, thus balancing electrode-injected NIR-generated holes. The optimized device achieved fivefold increase maximum luminance compared control. Additionally, it demonstrated fast optical response, broad modulation range, significant potential bioimaging applications, achieving resolution 1693 dpi. approach provides effective solution enhancing UCDs.

Language: Английский

Citations

0
Large-photosensitive-area InGaAs(P) near-infrared single-photon detector with a low dark-count rate at 203 K DOI Creative Commons
Yakui Dong, Chao Feng,

Linshan Sun

et al.

Cell Reports Physical Science, Journal Year: 2025, Volume and Issue: unknown, P. 102446 - 102446

Published: Feb. 1, 2025

Language: Английский

Citations

0
Deviate from the norm: ambipolar-acceptor frameworks as a new design paradigm for low bandgap conjugated polymers DOI Creative Commons
Wyatt D. Wilcox,

Evan W. Culver,

Nicolas C. Nicolaidis

et al.

Journal of Materials Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A series of low bandgap polymers demonstrate a new design model that pairs the ambipolar unit thieno[3,4- b ]pyrazine with traditional acceptors to give bandgaps ca. 1 eV, initial non-optimized devices showing promise as NIR photodetectors.

Language: Английский

Citations

0
Bias‐Switchable Photomultiplication and Photovoltaic Dual‐Mode Near‐Infrared Organic Photodetector DOI Open Access
Yijun Huang, Lin Shao, Yazhong Wang

et al.

Advanced Materials, Journal Year: 2025, Volume and Issue: unknown

Published: March 6, 2025

Photomultiplication-type organic photodetectors (PM-OPDs) provide for signal amplification, ideal detecting faint light, and simplifying detection systems. However, current designs often suffer from slow response speed elevated dark current. Conversely, photovoltaic-type (PV-OPDs) fast high specific detectivity (D*) but have limited photoresponse. This study presents the synthesis incorporation of a non-fullerene acceptor, BFDO-4F, into active layer to introduce trap states capturing photogenerated electrons. The resulting device exhibits dual-mode characteristic is bias-switchable between PV PM-modes. In PV-mode, OPDs achieve D* 1.92 × 10¹2 Jones time 2.83/4.43 µs. PM-mode, exhibit exceptional external quantum efficiency (EQE) up 3484% 1.13 Jones. An on-chip self-powered module with PV-mode pixels driving PM-mode pixel demonstrated, yielding photocurrent approximately five times higher than reference device. approach paves way developing multifunctional OPDs, suitable various applications.

Language: Английский

Citations

0
Squaraine Dyes for Organic Photomultiplication Photodetectors with 220% External Quantum Efficiency at 1240 nm DOI Creative Commons

Joshua Csucker,

Elodie Didier,

João Pedro Ferreira Assunção

et al.

Advanced Science, Journal Year: 2025, Volume and Issue: unknown

Published: April 3, 2025

Abstract Near‐infrared (NIR) light detection at wavelengths λ > 1100 nm is essential in modern science and technology. Emerging organic semiconductors are promising for solution‐processed, flexible, large‐area NIR photodetectors (OPDs), but only a few chromophores with peak absorption beyond the silicon bandgap available. Furthermore, external quantum efficiency (EQE) specific detectivity (D * ) of OPDs restricted by insufficient exciton dissociation high dark/noise current. Here, combination strong electron‐accepting ‐donating groups used to synthesize selection novel squaraine dyes superior redshifted absorptions, peaking 1165 solution extending 1240 blend film. To overcome tradeoff between long wavelength photoresponse, photons detected utilizing gain OPD design, where photomultiplication occurs via hole trap‐induced injection charges. The can achieve an EQE 220% still maintains 25% tail 1400 nm, thereby surpassing existing broad range nm. measured maximum D equals 10 9 Jones estimated from shot noise ≈10 11 Jones, independent bias voltage.

Language: Английский

Citations

0
Tailored Non‐Fullerene Acceptors for Efficient Electron Trapping and High Photomultiplication in Flexible Organic Photodetectors DOI
Shuaiqi Li, Lin Shao, Yazhong Wang

et al.

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 7, 2025

Abstract Photomultiplication‐type organic photodetectors (PM‐OPDs) are highly effective for detecting weak optical signals; however, achieving a balance between high gain, broad spectral sensitivity, fast response, and low operating voltage remains significant challenge. In this study, solution‐processed approach utilizing tailored non‐fullerene acceptors (NFAs) is presented to enhance electron trapping enable efficient photomultiplication. Two NFAs, BFDO‐Eh‐4F BPDO‐Eh‐4F, with distinct LUMO levels, synthesized incorporated as dopants. Devices incorporating demonstrated an exceptional external quantum efficiency (EQE) of 2500% at 2 V bias rapid response time 420 µs, attributed its deeper level that facilitates trapping. Conversely, BPDO‐Eh‐4F‐based devices operated in photovoltaic (PV) mode due weaker arising from shallower level, dark current specific detectivity ( D *) 4.5 × 10¹ Jones. These findings elucidate the role unbalanced charge transport holes electrons enhancing PM‐OPD performance highlight critical influence offsets optimizing The complementary advantages these position them promising candidates applications imaging, communication biosensing, providing clear pathway development next‐generation OPDs balanced performance.

Language: Английский

Citations

0
Recent advances in small-molecular acceptors for near-infrared organic photodetectors: mechanisms, materials, and challenges DOI
Shabaz Alam,

Suhui Sim,

Meng Qiang Li

et al.

Materials Today Chemistry, Journal Year: 2025, Volume and Issue: 46, P. 102718 - 102718

Published: April 22, 2025

Language: Английский

Citations

0
Exploration of a proquinoidal [1,2,5]thiadiazolo[3,4-g]quinoxaline-based small molecule acceptor toward high-sensitivity shortwave infrared photodetection DOI
Wei‐Qi Zhang, Qingxia Liu, Yuan Liu

et al.

Journal of Materials Chemistry C, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

A novel small molecule acceptor (TQpp) was developed for VIS-SWIR broadband photodetection. The TQpp-based device achieves 18.4% EQE and 1×10¹² Jones at 1100 nm, enabling high-precision real-time pulse monitoring under ultralow 1064 nm illumination.

Language: Английский

Citations

0
Flexible Near‐Infrared Organic Photodetectors With Ultralow Dark Current by Layer‐by‐Layer Blade Coating DOI

Yingze Zhang,

Wenliang Chen, Junhui Miao

et al.

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 10, 2024

Abstract Near‐infrared organic photodetector (NIR OPD) is promising for emerging wearable biosensing applications. However, their practical application hindered by the high dark currents of devices that limit detection faint light. In this work, highly sensitive flexible NIR OPDs are presented with ultralow currents, fabricated using a layer‐by‐layer blade coating (LBL‐BC) technique. active layer, fully fused‐ring molecule FM2, featuring fixed molecular skeleton, employed as an electron acceptor to reduce trap density. The LBL‐BC method enhances film order and phase purity significantly reduces density states, optimizes vertical separation structure thin film, thereby preventing reverse charge injection. As result, OPD developed exhibiting current 4.83 × 10 −9 A cm −2 at −0.3 V bias extremely low noise 7.65 −15 Hz −1/2 Hz, comparable commercial silicon photodiodes. Furthermore, device successfully applied real‐time monitoring human heartbeat rate, oxygen saturation, motion recognition. These findings advance development in technologies.

Language: Английский

Citations

2
Terminal Fluorination Modulates Crystallinity and Aggregation of Fully Non‐Fused Ring Electron Acceptors for High‐Performance and Durable Near‐Infrared Organic Photodetectors DOI Open Access
Wenxu Liu,

Wenjing Guo,

Lulu Fu

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Nov. 6, 2024

Abstract High dark current density ( J d ) severely hinders further advancement of near‐infrared organic photodetectors (NIR OPDs). Herein, we tackle this grand challenge by regulating molecular crystallinity and aggregation fully non‐fused ring electron acceptors (FNREAs). TBT‐V‐F, which features fluorinated terminals, notably demonstrates crystalline intensification a higher prevalence predominance J‐aggregation compared to its chlorinated counterpart (TBT‐V‐Cl). The amalgamation advantages confers TBT‐V‐F‐based OPDs with lower nonradiative energy loss, improved charge transport, decreased energetic disorder, reduced trap density. Consequently, the corresponding self‐powered exhibit 40‐fold decrease in , remarkable increase detectivity D * sh ), faster response time, superior thermal stability TBT‐V‐Cl‐based OPDs. Further interfacial optimization results an ultra‐low 7.30×10 ‐12 A cm −2 over 10 13 Jones 320–920 nm wavelength climax 2.2×10 14 at 800 for OPDs, representing one best reported date. This work paves compelling material‐based strategy suppress highly sensitive NIR while also illustrates viability FNREAs construction stable affordable real‐world applications.

Language: Английский

Citations

2