Perovskite Photodetectors Research Articles

Dual-functional electrostatic self-assembly nanoparticles enable suppressed defects and improved charge transport in perovskite optoelectronic devices

The performance of perovskite solar cells and photodetectors strongly depends on the carrier extraction in the electron transport layer/perovskite interface and the film quality of the perovskite layer. Ti3C2Tx MXene quantum dots, which exhibit both good conductivity of MXene materials and size-dependent tunable optoelectronic properties of quantum dots, were synthesized to form electrostatic self-assembly nanoparticles and further introduced into perovskite optoelectronic devices. The carrier extraction in electron transport layer/perovskite interface was significantly improved, and the defect density of the modified perovskite layer was effectively reduced. These improvements ultimately lead to a remarkable power conversion efficiency of perovskite solar cells increasing from 16.57 % to 23.47 %, and the photodetectors achieve responsivity approaching 35.54 mA W−1 and response speed of 154 ms (rise time) and 120 ms (decay time). Meanwhile, the long-time humidity, thermal and light stress stability of the devices were largely boosted, which originated from the better crystallization and suppressed degradation of the perovskite films.

Antisolvent-Treated MAPbI3 and PbS Quantum Dots for High-Performance Broadband Photodetectors

Nowadays, halide perovskites have drawn extensive attention as active layers in the field of photodetectors (PDs) attributed to their optoelectric properties. However, the numerous defects in the prepared films and the lack of response in the near-infrared (NIR) range due to the intrinsic band gap limitation severely restrict the performances and applications of perovskite photodetectors. With this in mind, we introduced diethyl ether as a counter-solvent to improve the quality of the peroxide films. After comparison with chlorobenzene (CB), toluene (ToL), and ethyl acetate (EA), the mechanism by which diethyl ether (DE) as an antisolvent improves the quality of the films was explored. MAPbI3 films and lead sulfide (PbS) quantum dots (QDs) were then combined to achieve a visible (VIS)–near-infrared response. The resultant PD, with the structure of ITO/NiOx/PbS QDs/MAPbI3/PC61BM/Ag, exhibits an ultrabroad response from 300 to 1100 nm and presents high detectivity reaching 5.6 × 1011 and 6.5 × 1010 Jones in the VIS and NIR regions, respectively. The fast response time in the microsecond range and the response bandwidth of 10 kHz (f–3 dB) are comparable or even superior to counterparts. In addition, this approach provides ideas for the development of high-performance broadband perovskite-based optoelectronic devices.

Flexible, stable, and self-powered photodetectors embedded with chemical vapor deposited lead-free bismuth mixed halide perovskite films

The emerging revolution in the field of Internet of Things (IoT) necessitates the development of flexible, self-powered, and cost-effective photodetectors such as metal halide-based perovskite photodetectors. Lead-free ternary metal halides have emerged as a promising option having no technical barrier with regard to toxicity. However, the performance metrics of lead-free ternary metal-halide-based optoelectronic devices lags behind those of conventional lead-halide-based devices. In this study, we demonstrate that chemical-vapor-deposited methylammonium bismuth iodide (MA3Bi2I9 (MBI)) films and their mixed halide analogues (MA3Bi2I6Br3 (MBIB)) and MA3Bi2I6Cl3 (MBIC)) enhance the performance metrics and stability of photodetectors by enabling the growth of films with smooth and compact morphology. MBIC-integrated devices achieved a responsivity of ∼ 0.92 A/W and specific detectivity of ∼ 2.9 × 1013 Jones under no bias and UV (382 nm) illumination, which is approximately-three times higher than MBI counterparts. They also exhibit outstanding operational stability by maintaining 94 % of the photoresponse after illumination for 500 h (382 nm wavelength at light intensity of 1.0 mW/cm2) in ambient air. Furthermore, these devices show satisfactory mechanical stability, with the attenuation being as low as 15 % of initial photoresponse after bending for 5,000 cycles at 5 % tensile strain. Our findings indicate that MBIC film-integrated devices have immense potential in optoelectronics.

Highly Sensitive Tin-Lead Perovskite Photodetectors with Over 450 Days Stability Enabled by Synergistic Engineering for Pulse Oximetry System.

Low-bandgap tin (Sn)-lead (Pb) halide perovskites can achieve near-infrared response for photodetectors. However, the Sn-based devices suffer from notorious instability and high defect densities due to the oxidation propensity of Sn2+ . Herein, a multifunctional additive 4-amino-2,3,5,6-tetrafluorobenzoic acid (ATFBA) is presented, which can passivate surface defects and inhibit the oxidation of Sn2+ through hydrogen bonds and chelation coordination from the terminal amino and carboxyl groups. The perfluorinated benzene ring structure of ATFBA affords the passivator assembled at the grain boundaries to enhance the water resistance. With the synergistical passivation of these functional groups, the Sn-Pb perovskite photodetector exhibits a remarkable responsivity of 0.52AW-1 and an excellent specific detectivity of 5.34×1012 Jones at 850nm, along with remaining 97% of its initial responsivity over 450 days. Benefitting from high sensitivity, the photodetector is integrated into a pulse oximetry sensor visualization system, yielding accurate blood oxygen saturation and heart rate with less than 2% error. This work paves the avenue toward constructing high-performance and stable Sn-Pb perovskite photodetectors for practical applications.

Enhancing the UV Response of All-Inorganic Perovskite Photodetectors by Introducing the Mist-CVD-Grown Gallium Oxide Layer

All-inorganic perovskites, with their low-cost, simple processes and superior heat stability, have become potential candidate materials for photodetectors (PDs). However, they have no representative responsivity in the deep-ultraviolet (UV) wavelength region. As a new-generation semiconductor, gallium oxide (Ga2O3), which has an ultrawide bandgap, is appropriate for solar-blind (200 nm–280 nm) deep-UV detection. In this work, ultrawide-bandgap Ga2O3 was introduced into an inorganic perovskite device with a structure of sapphire/β-Ga2O3/Indium Zinc Oxide (IZO)/CsPbBr3. The performance of this perovskite PD was obviously enhanced in the deep UV region. A low-cost, vacuum-free Mist-CVD was used to realize the epitaxial growth of β-Ga2O3 film on sapphire. By introducing the Ga2O3 layer, the light current of this heterojunction PD was obviously enhanced from 10−8 to 10−7, which leds its detectivity (D*) to reach 1.04 × 1012 Jones under a 254 nm light illumination with an intensity of 500 μW/cm2 at a 5 V bias.

Single-pixel color imaging based on a high-performance MAPbI3 perovskite photodetector

Metal halide perovskites with excellent optoelectronic properties show great promise in optical imaging. However, the complex fabrication process of high-density perovskite image sensors limits its development. Herein, we report a simple perovskite color imaging system by combining a single high-performance perovskite photodetector (PD) and the advanced Fourier single-pixel imaging algorithm. We introduce an atomic layer deposition-TiO2 layer and a Spiro-OMeTAD layer to optimize the band energy level arrangement of the perovskite PD, suppressing the dark current and improving the photocurrent of the device, respectively. The optimized perovskite PD with flat spectral response covering all visible wavelength exhibits a high responsivity of 238 mA/W at zero bias, a high special detectivity of 1.13 × 1013 Jones, and a linear dynamic range of 132 dB. In order to bypass the fabrication of the high-density perovskite PD array, we set up a single-pixel imaging system based on an optimized high-performance perovskite PD, demonstrating a high-quality color imaging result. This work provides a perspective for perovskite image sensors and injects vitality into the single-pixel imaging technology.

High-performance hybrid graphene-perovskite photodetector based on organic nano carbon source-induced graphene interdigital electrode film on quartz substrate

Hybrid graphene interdigital electrode-perovskite structure has demonstrated high value in the photodetector (PD) due to high absorbance and carrier collection efficiency. However, direct pattern of graphene film on the dielectric substance still faces huge challenges. Especially, the involvement of multi-step transfer and high-energy etching process hamper its development.In this context, we propose an organic nano carbon source (ONCS). Direct pattern of graphene film on the quartz substrate (GFqtz) is attained by the calcination of patterned ONCS film for the first time, which is simply achieved by screen printing technology thanks to the gel state. The transformation mechanism from ONCS to GFqtz has been proposed. In detail, the ONCS in-situ react with the quartz substrate to induce the SiC nanocrystals layer during the calcination. Then, the graphene film composes of the non-ordered graphene crystal layer and the aligned graphene crystals layer. Finally, the perovskite PD are successfully constructed by the GFqtz interdigital electrode. Compared to the PD fabricated by the Au interdigital electrode, the GFqtz-perovskite PD present an ultra-low detective light power density (0.5 μW/cm2) at 1 V bias voltage. The maximum responsivity and defectivity (0.1 A/W) and D* (2.6 × 1011 Jones) of the GFqtz-perovskite PD demonstrate an order of magnitude higher than the Au-perovskite PD's value.

Surface treatment of triple cation mixed perovskite for highly stable lateral photodetectors with low dark current

Owing to their remarkable optoelectronic properties, three-dimensional (3D) organic-inorganic hybrid perovskites are considered as promising candidate materials for highly sensitive photodetectors (PDs). However, intrinsic instability and high dark current of bare 3D perovskite-based PDs are limiting their potential applications. In this paper, we utilized three different ammonium salts, including the alkyl methylammonium iodide (MAI), single-ring aromatic phenylmethylammonium iodide (PMAI), and fused-ring aromatic 1-naphthylmethylamine iodide (NMAI), to treat the 3D triple cation (Cs/FA/MA) mixed perovskite film, respectively. Most notably, the PMAI treatment generates a two-dimensional (2D) (PMA)2PbI4 capping layer on the top of the 3D mixed perovskite film. The 2D layer not only passivates the surface undercoordinated iodide ions defects of the 3D perovskite film, but also protects the film from oxygen and water penetration. As a result, the PMAI-treated perovskite PD exhibits an ultra-low dark current (5.49 × 10−11 A at a 10 V bias), a high on/off ratio (∼4 × 103) and good long-term air stability. The imaging capability is also demonstrated in the bilayer device.

Self-powered CH3NH3PbI3 perovskite photodiode with a noise-suppressible passivation layer of poly(methyl methacrylate).

Organohalide perovskite materials and related optoelectronic applications have drawn significant attention due to their promising high-performance photon-to-electricity conversion efficiencies. Herein, we demonstrate a highly sensitive self-powered perovskite-based photodetector created with a noise-current-suppressible passivation layer of poly(methyl methacrylate) (PMMA) at the interface between a CH3NH3PbI3 light-absorbing layer and a NiOx hole-transporting layer. Along with the defect passivation effect, the PMMA layer effectively diminishes unwanted carrier recombination losses at the interface, resulting in a significant reduction of the leakage/noise current. Consequently, without external bias, a remarkably high level of specific detectivity (∼4.5 × 1013 Jones from the dark current and ∼0.81 × 1012 Jones from the noise current) can be achieved due to the use of the PMMA passivation layer, greatly exceeding those of conventional unpassivated perovskite devices. Moreover, we observed a very wide linear dynamic response range of ∼129 dB together with rapid rise and decay response times of ∼52 and ∼18 µs, respectively. Overall, these results provide a solid foundation for advanced interface-engineering to realize high-performance self-powered perovskite photodetectors for various optoelectronic applications.

Water-soluble Ag2S QD modified CsPbI2Br heterojunction photodetector with ultra-low dark current and ultra-fast response speed

Mixed halide inorganic perovskite CsPbI3-xBrx has attracted attention in the field of optoelectronics. As a desirable photoactive material, the application of CsPbI2Br in the field of photodetector (PD) remains to be explored. The synergistic passivation strategy based on Ag2S quantum dot (QD) aqueous solution improves the morphology of the CsPbI2Br perovskite film. At the same time, Ag2S/CsPbI2Br bulk heterojunction optimizes the energy level arrangement between perovskite and Au electrode, improves the carrier transmission and collection capacity, and thus improves the performance of PD. Ag2S/CsPbI2Br bulk heterojunction PD has an ultra-low dark current of 7.74 pA, an ultra-fast response speed of 2.95/3.07 μs, and a high switching ratio of 7.67 × 105. This work provides a method for the preparation of high-quality mixed halide perovskite materials and a strategy for the development of high-performance perovskite PDs based on bulk heterojunction.

High-performance p-i-n perovskite photodetectors and image sensors with long-term operational stability enabled by a corrosion-resistant titanium nitride back electrode.

Despite the impressive developments in perovskite optoelectronic devices, their long-term stability remains a major challenge. Chemical reactions and ion exchange at the metal/perovskite contact interface are two significant factors that lead to the failure of perovskite devices. To address this issue, a titanium nitride (TiN) layer is introduced as a robust corrosion-resistant coating between perovskite films and metal electrodes. By introducing TiN layer, a perovskite photodiode with dark current down to 3.25 × 10-11 A cm-2 is realized. Consequently, the TiN-based perovskite photodiode shows a specific detectivity of 1.21 × 1014 cm W-1 Hz1/2, which is approximately two orders of magnitude higher than that of the control device without a TiN layer. Under continuous illumination of a 520 nm green light for 576 000 cycles, the responsivity of the TiN-based photodetector remains at 94.27% of its initial value. The TiN-based photodetector exhibits superior stability under thermal stress. After aging at 85 °C for 572 h, the TiN-based photodetector retains 72% of its initial responsivity. Using the TiN-based photodiode, a perovskite image sensor containing 64 × 64 pixelated perovskite photodiodes is constructed over an amorphous silicon thin-film transistor (TFT) backplane. The perovskite image sensor exhibits real-time imaging capability and long-term stability for over 6 months. This study highlights the importance of using metallic nitrides to achieve high-performance and air-stable perovskite devices for optoelectronic applications.

Bio-inspired micro area concentrated array assisted perovskite photodetector toward weak light imaging

A perovskite photodetector with bio-inspired micro area concentrated structures has been fabricated for weak light imaging. The photodetector exhibits high detectivity (1.37 × 1013Jones), and it can achieve weak light imaging under 0.64 μW cm−2.

Molecular engineering for sensitive, fast and stable quasi-two-dimensional perovskite photodetectors

Molecular engineering contributes to a well-aligned stacking of low-dimensional compositions in quasi-two-dimensional perovskite thin-films, resulting in high performance and stable-operation photodetectors across the whole visible range.

Recent progress in construction methods and applications of perovskite photodetector arrays.

Metal halide perovskites are considered promising materials for next-generation optoelectronic devices due to their excellent optoelectronic performances and simple solution preparation process. Precise micro/nano-scale patterning techniques enable perovskite materials to be used for array integration of photodetectors. In this review, the device types of perovskite-based photodetectors are introduced and the structural characteristics and corresponding device performances are analyzed. Then, the typical construction methods suitable for the fabrication of perovskite photodetector arrays are highlighted, including surface treatment technology, template-assisted construction, inkjet printing technology, and modified photolithography. Furthermore, the current development trends and their applications in image sensing of perovskite photodetector arrays are summarized. Finally, major challenges are presented to guide the development of perovskite photodetector arrays.

Performance and stability enhancement of perovskite photodetectors by additive and interface engineering using a dual-functional PPS zwitterion.

Hybrid organic-inorganic metal halide perovskites (HOIPs) have gained significant research interest due to their tunable optoelectronic properties and ease of fabrication. Enhancing the stability and efficiency of perovskite materials can be achieved through the passivation of defective surfaces and the improvement of interfacial properties. In this study, we introduce a zwitterionic compound, PPS (3-(1-pyridinio)-1-propanesulfonate), as a bifunctional material that serves as an additive and an interlayer. Incorporating PPS into the perovskite film effectively reduces both positively and negatively charged defects, leading to improved surface morphology and a reduction in undesired charge carrier recombination. Additionally, the formation of a PPS interlayer on SnO2 improves the SnO2/perovskite interfacial characteristics, thereby enhancing charge carrier extraction. As a result, the photodetector exhibits a low dark current of 6.05 × 10-11 A, an excellent responsivity of 5.93 A W-1, a detectivity of 1.51 × 1013 J, and an on/off ratio of 1.2 × 104 under open-air conditions. Moreover, the device demonstrates outstanding stability, retaining 80% of its original responsivity in an ambient environment. This work highlights the great potential of dual-functional materials for defect passivation in future optoelectronic devices, emphasizing the importance of surface modification and interface engineering for improved performance and stability.

Exciton dynamics and photoresponse of a CVD-grown WS2/thermally evaporated CsSnBr3 heterostructure

Transition metal dichalcogenide (TMDC)/metal halide perovskite photodetectors provide a promising new route for the realization of high-performance photodetectors owing to their unique optoelectronic features.

Recent Progress of Narrowband Perovskite Photodetectors: Fundamental Physics and Strategies

Applications involving image sensors, computer vision, and optical communications all require adjustable spectral narrowband photodetectors. In recent years, because of their excellent optoelectronic characteristics, metal halide perovskites have drawn a great deal of interest. Bearing these properties, narrowband photodetectors using perovskites as either active or other functional layers have demonstrated excellent performance, covering both wide and tunable spectral range. In this review, latest advancements in narrowband perovskite photodetectors are outlined, focusing on fundamental physics, implemented strategies, and new opportunities for the realization of narrowband detection. The device physics of photodetectors are comprehensively reviewed followed by the key conventional implementation strategies for narrowband detection based on traditional semiconductor materials and solution-processable materials (organics, quantum dots). After brief description of the material and morphological properties of perovskites, emphasis is put on the most recent developments of the strategies for narrowband perovskite photodetectors. While clarifying several narrowband detection strategies, innovative device architectures, respective applications, and existing limitations are analyzed in detail along with the discussion of the feasibility of applying the traditional strategies to perovskite materials for narrow spectral detection. Finally, considering both the perspective and the current challenges, an outlook of the future development in this rapidly evolving field of perovskite narrowband photodetection is presented for a wider scope of theoretical research and promising technological developments.

Multimodal photodetectors with vacuum deposited perovskite bilayers

A bilayer perovskite photodetector that operates in broadband and narrowband modes, depending on the illumination side, is presented. It consists of two perovskite films with different bandgaps, separated by a metal oxide layer to avoid intermixing.

High-performance flexible and self-powered perovskite photodetector enabled by interfacial strain engineering

The spin–orbit coupling (SOC) strength in a perovskite film is enhanced by regulating the lattice strain with PDCBT layer, resulting in a high-performance flexible and self-powered perovskite photodetector.

Highly stable, substrate-free, and flexible broadband halide perovskite paper photodetectors.

In this work, we aim to fabricate a highly stable and flexible perovskite paper photodetector based on a Zn-doped MA0.6FA0.4PbI3 perovskite and CNC. The paper photodetector has been successfully synthesized by the vacuum filtration method and deposited with interdigitated electrodes. The paper photodetector exhibits a significant photoresponse with a responsivity of 0.23 A W-1 under 650 nm light irradiation when operated at 5 V. The stability of the paper photodetector has also been tested and it shows high photoresponse after 30 days under ambient conditions. Therefore, this paper photodetector holds promise for developing efficient, stable, and flexible optoelectronic devices in the future.