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Cesium lead bromide (CsPbBr3) perovskite photodetectors (PDs) are attractive for applications in visible light communication (VLC) due to ultra‐high detectivity and fast response speed. However, the fabrication of high‐quality CsPbBr3 polycrystalline films using solution‐based process is very challenging. Due to the low solubility of CsBr in precursor solutions, solution‐processed CsPbBr3 films are typically discontinuous and porous, hindering the performance of resulting PDs. Herein, a facile and modified sequential spin‐coating method is introduced to prepare high‐crystallinity, pinhole‐free CsPb2Br5‐CsPbBr3 perovskite films with an average grain size of ≈1 µm. The hole‐transport‐layer‐free (HTL‐free) PDs based on the CsPb2Br5‐CsPbBr3 perovskite films show high performance parameters, including the responsivity of 0.11 A W−1, the detectivity of 1.4 × 1012 Jones, a linear dynamic range of 128.6, and an on/off ratio of 1.5 × 106. The PDs outperform other HTL‐free perovskite PDs and are comparable to the p–i–n perovskite PDs reported in the literature. In addition, the high‐performance CsPb2Br5‐CsPbBr3 PDs are applied in VLC by using the PD as a self‐powered signal receiver of voice commands in a simulated room. This work uniquely combines the features of high‐performance self‐powered perovskite PDs with VLC techniques, paving the path to wide applications of all‐inorganic perovskite PDs. [ABSTRACT FROM AUTHOR]

Organic–inorganic metal halide perovskites have achieved great success in applications such as light-emitting diodes, photodetectors (PDs) and solar cells due to their high light absorption coefficients, tunable band gaps and simple solution-process technologies. However, their polycrystalline films have low carrier mobility and high defect states, which limit the device performance. As substitutes, perovskite microcrystal (MC) films exhibit higher carrier mobility and lower defect state density and thus, they have received much attention in recent years. Herein, we introduce MAPbX3 (X = Br, I) MC films with controllable thickness and adjustable band gap, and the self-powered MAPbI3 perovskite MC PDs (MCPDs) with a structure of ITO glass/perovskite MC film/carbon have been assembled for the first time. By optimizing the thickness of the MC film, our hole-transport-layer-free (HTL-free) PDs exhibit excellent self-powered performance, with an on/off ratio as high as 2 × 105, the rise/fall time of 80/580 μs, the responsivity of 0.26 A W−1, the detectivity of 7.01 × 1011 Jones and the linear dynamic range of 107 dB. In addition, our MCPDs without encapsulation show excellent light and storage stability. These results indicate a good method for preparing high-performance and high-stability perovskite MC devices. [ABSTRACT FROM AUTHOR]

Owing to good crystal structure and novel one-dimensional (1D) outer surface, MAPbI3 nanowires (NWs) show fewer grain boundaries, lower defect density and longer carrier lifetime as compared with their polycrystalline thin films, leading to MAPbI3 NWs exhibiting higher quantum efficiencies in optoelectronic devices. Herein, by a simple two-step spin-coating method with the addition of various N,N-dimethylformamide (DMF) contents, a PbI2–DMF adduct is formed; this changes the micro-morphology of MAPbI3 perovskite from 3 dimensional (3D) nanocubic to 1D NW. Through optimizing the DMF contents, MAPbI3 NWs with strongest light absorbability and best crystallinity have been obtained (500 μL DMF). In addition, photodetectors (PDs) are assembled with various DMF amounts on glass substrates, and the optimal MAPbI3 NW PD (500 μL DMF) shows the best performance with on/off ratio greater than 250; the rise and decay times are 12 and 22 ms, respectively. Furthermore, a flexible MAPbI3 NW PD is assembled, and it shows good sequential and stable response with the on/off ratio of more than 45. Notably, under various bending curvatures and many cycles, the performance of the flexible NW device has only slight degradation. Our results may have great value for the application of flexible MAPbI3 NW devices in the future. [ABSTRACT FROM AUTHOR]

A self-powered CH 3 NH 3 PbI 3 photodetector (PD) based on ZnO microsphere (MS) array scaffold was reported. Through scanning electron microscopy images, a ZnO microsphere array consisted of nanosheets can be seen on ZnO mesh structure. Based on this novel structure, we first fabricated CH 3 NH 3 PbI 3 photodetector with ZnO MS as the electron selective layer and MoO 3 hole selective layer. Under light, the PDs showed the detection wavelength ranges from 300 to 800 nm, the responsivity values up to 48 mA/W, detectivity values as large as 4.5 × 10 11 Jones, on/off ratio up to 1400, and rise and fall time less than 14 ms, these results are comparable with the reported perovskite PDs. Furthermore, because of the effective absorption for ZnO microsphere in ultraviolet (UV) region, our device showed a significant UV detection performance. These results have great value on the scaffolds of perovskite materials for high performance devices. [ABSTRACT FROM AUTHOR]

Self-powered light-emitting photodetectors (SLEPs) can simultaneously transmit and receive information using light, offering huge potential for applications in interactive communication systems. However, high-performance SLEPs are very hard to achieve due to the seriously contradictory principles of carrier transport in SLEPs. In this study, a novel structure based on a ZnO hollow ball/CsPbBr3 heterojunction, in which ZnO hollow balls function as an ultraviolet (UV) response center and CsPbBr3 is designed to be a green light-emitting material, is reported as a high-performance SLEP. Since the ZnO hollow balls have superior light trapping characteristics for UV light, the device shows a huge UV response with the on/off ratio and detectivity up to 16 527 and 2.4 × 1013 Jones, respectively. Moreover, it displays blue emission with a low threshold voltage because of CsPbBr3. Compared with the traditional ZnO/GaN structure devices, the device showed enhanced dual-functional performance at various wavelengths due to the insertion of CsPbBr3, which resulted in a better contact interface and green-light emission center. Our structure separating the light-responsive and emitting active regions avoids the contradictory principles of carrier transport, which may provide new access to gain high-performance dual-functional devices. [ABSTRACT FROM AUTHOR]

Achieving high responsivity for a self-powered ultraviolet (UV) photodetector is challenging. Herein, we report a high responsivity self-powered UV photodetector based on a ZnO nanoarrays/GaN structure with a CdS insert layer whose responsivity reached as high as 176 mA W−1 at 300 nm, which is larger than the values of previously reported ZnO-based self-powered UV PDs. Moreover, based on the optimized CdS thickness with 5 cycle times, more than 1000 for the Iph/Idark ratio at the reverse biases was achieved. The device showed a good visible-blind UV photoresponse characteristic with the UV-visible responsivity ratio (R300nm/R500nm) reaching 48. Moreover, below the 350 nm UV region, the detectivity of the ZnO/CdS core–shell array PD was above 1012 cm Hz1/2 W−1, which is equivalent to that of the commercially available UV-enhanced Si photodiodes. The excellent photoelectric properties of the n-ZnO/CdS/p-GaN structure described above is due to the CdS insert layer, which was used as a carrier transition layer and realized a stepped energy level structure to effectively reduce the interfacial charge recombination and facilitate electron transfer. [ABSTRACT FROM AUTHOR]

In this paper, we will report the geometrical morphology, optical properties, electrical properties of the gallium doped ZnO nanorods (GZO NRs), as well as the performance of Au/GZO NRs/Au structure photodetector. We found that with the increase of the molar ratio of gallium, the length of the nanorods becomes smaller and the radial width increases, and the shape is more toward the hexagonal prism, and the grain radius increases. Also with the increase of the doping ratio, the optical absorption edge had a blueshift phenomenon, and the conductivity is enhanced. Moreover, in order to obtain the high performance of the photodetector, GZO NRs were treated by hydrogen peroxide and ohmic contact Au/GaZnO Nanorods/Au device was changed to a Schottky contact device, which showed a smaller dark current and faster response speed compared with ohmic contact device. [ABSTRACT FROM AUTHOR]

All‐inorganic halide perovskite is considered as outstanding candidate of organic–inorganic hybrid perovskite due to its superior stability. However, the low solubility of precursor and uncontrollable film growth result in poor film quality and impede the application of polycrystalline films greatly. In this work it is reported on a space‐confined growth strategy to overcome the low solubility and fast crystal growth disadvantages via freezing the precursor solution within the gaps of ordered polystyrene sphere templates. Then, the dense CsPbBr3 polycrystalline films realize low trap density (3.07 × 1012 cm−3) and high carrier mobility (9.27 cm2 V−1 s−1) after stoichiometric modulation. Photodetectors based on these films exhibit high performance in all figures of merit. Specifically, high responsivity up to 216 A W−1 and ultrashort response time (<5 µs) are achieved, which are better than those of all the CsPbBr3 based PDs. A record detectivity of 7.55 × 1013 and 3.1 × 105 Hz −3 dB bandwidth are also achieved. This work opens the window of high quality all‐inorganic halide perovskite polycrystalline films and can be extended to rational application of more optoelectronic devices including solar cells, photoelectrodes, and ray detectors. A space‐confined growth strategy is applied to overcome the low solubility and fast crystal growth disadvantages of CsPbBr3 polycrystalline films. The dense films can realize low trap density and high carrier mobility after stoichiometric modulation. Photodetectors based on these films exhibit high performance in all figures of merit, such as detectivity, linear detection range, and response time. [ABSTRACT FROM AUTHOR]

Abstract The use of aligned one-dimensional nanostructures as scaffolds in organic-inorganic hybrid perovskite photodetectors (PDs) has attracted significant attention due to their large surface area-to-volume ratio and efficient electron transport capability in the radial direction. Here, we report CH 3 NH 3 PbI 3 (MAPbI 3) perovskite photodetectors (PDs) with Ga-doped ZnO nanorods (GZO NRs), prepared by the water bath method, as a scaffold-structure electron transport layer (ETL). Our MoO 3 hole transport layer (HTL) based perovskite PDs using GZO NRs as a scaffold showed a larger light/dark current (I ph / I dark) ratio, higher responsivity and detectivity than those of the undoped ZnO NRs/MAPbI 3 devices at zero bias. These enhancements are attributed to the incorporation of Ga atoms into the ZnO NRs, which reduce the density defect states of ZnO NRs and improves the performance of MAPbI 3 perovskite PDs. In addition, by taking advantage of the GZO NRs scaffold structure, a HTL-free perovskite PD was prepared by using graphite electrodes. The graphite-connected device shows self-powered PD performances with an I ph / I dark ratio of ~2.5 × 103, responsivity of above 0.3 A/W and detectivity of 1.3 × 1012 Jones, all of which are comparable with those of MoO 3 HTL based perovskite PDs. Graphical abstract Our MoO 3 hole transport layer (HTL) based perovskite PDs using GZO NRs as a scaffold showed a larger light/dark current (I ph / I dark) ratio, higher responsivity and detectivity than those of the undoped ZnO (UZO) NRs/MAPbI 3 devices at zero bias. In addition, a HTL-free perovskite PD prepared by using graphite electrodes shows self-powered PD performances with an I ph / I dark ratio of ~ 2.5 × 103, responsivity of above 0.3 A/W and detectivity of 1.3 × 1012 Jones, all of which are comparable with those of MoO 3 HTL based perovskite PDs. fx1 Highlights • The perovskite photodetector with GZO NRs scaffold showed a larger I ph / I dark ratio, higher responsivity and detectivity than those of the undoped ZnO devices at zero bias. • The enhancements are attributed to the incorporation of Ga elements in ZnO NRs, which reduces defect states of ZnO nanorods. • A HTL-free perovskite PD shows highly self-powered performances with the I ph / I dark ratio of ~2.5 × 103, responsivity of above 0.3 A/W and detectivity of 1.3 × 1012 Jones. [ABSTRACT FROM AUTHOR]

All-inorganic cesium lead halide perovskites have attracted intensive interest as light absorbing materials due to their large absorption coefficient, long charge carrier lifetime and diffusion length, especially they show better stability than their organic and inorganic hybrid counterparts. Herein, we demonstrate a high-performance self-powered CsPbBr 3 perovskite photodetector based on an all-inorganic structure. Our self-powered devices show high performance with the responsivity of 0.3 A/W, detectivity of 1.15 × 10 13 cm Hz 1/2 /W and on/off ratio of 4.5 × 10 2 . Notably, ZnO nanorods as a scaffold, which functions as a protection layer, are used to effectively enhance the stability and durability of perovskite photodetectors. Our all-inorganic device exhibits improvement of the stability in the air, has a certain high temperature endurance and shows the anti-corrosion ability to water and alcohol. These good performances and high stability present a potential application in harsh environments without external power sources. [ABSTRACT FROM AUTHOR]

A self-powered visible-blind ultraviolet (UV) photodetector based on n -Ga:ZnO nanorods (GZO NRs)/ p -GaN heterojunction was reported, in which the n -type GZO NRs were prepared by the water bath method. In this study, we found n -GZO NRs/ p -GaN heterojunction devices showed better performance than those of n -ZnO NRs/ p -GaN heterojunction devices in terms of the ratio I ph /I dark , responsivity and detectivity. Under UV illumination with the light intensity of 1.31 mW/cm 2 , the ratio I ph /I dark for the n -GZO NRs/ p -GaN heterojunction was as high as 3.2 × 10 5 at zero bias, which is about 75 times greater than that of an un-doped device (only 4.2 × 10 3 ). Also its responsivity reached 0.23 A/W which was three times larger than that of n -ZnO NRs/ p -GaN (∼0.08 A/W). The reason n -GZO NRs/ p -GaN heterojunction displayed lager light/dark current ratio, higher responsivity and detectivity, and more reliable self-powered performance at zero bias may be that in GZO NRs, the Ga-doping reduced the defect states in the nanorods, enhanced the conductivity and electron mobility of the ZnO material and benefited the photo-generated carriers transmission. [ABSTRACT FROM AUTHOR]

Mycoviruses have been found in various fungal species across different taxonomic groups, while no viruses have been reported yet in the fungus Exserohilum rostratum. In this study, a novel orfanplasmovirus, namely Exserohilum rostratum orfanplasmovirus 1 (ErOrfV1), was identified in the Exserohilum rostratum strain JZ1 from maize leaf. The complete genome of ErOrfV1 consists of two positive single-stranded RNA segments, encoding an RNA-dependent RNA polymerase and a hypothetical protein with unknown function, respectively. Phylogenetic analysis revealed that ErOrfV1 clusters with other orfanplasmoviruses, forming a distinct phyletic clade. A new family, Orfanplasmoviridae, is proposed to encompass this newly discovered ErOrfV1 and its associated orfanplasmoviruses. ErOrfV1 exhibits effective vertical transmission through conidia, as evidenced by its 100% presence in over 200 single conidium isolates. Moreover, it can be horizontally transmitted to Exserohilum turcicum . Additionally, the infection of ErOrfV1 is cryptic in E. turcicum because there were no significant differences in mycelial growth rate and colony morphology between ErOrfV1-infected and ErOrfV1-free strains. This study represents the inaugural report of a mycovirus in E. rostratum , as well as the first documentation of the biological and transmission characteristics of orfanplasmovirus. These discoveries significantly contribute to our understanding of orfanplasmovirus., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Jia, Nan, Song, Chen, Xia, Cheng, Zhang and Mu.)

To establish high-bandwidth chip-to-chip interconnects in optoelectronic integrated circuits, requires high-performance photon emitters and signal receiving components. Regarding the photodetector, fast device concepts like Schottky junction devices, large carrier mobility materials and shrinking the channel length will enable higher operation speed. However, integrating photodetectors in highly scaled ICs technologies is challenging due to the efficiency-speed trade-off. Here, we report a scalable and CMOS-compatible approach for an ultra-scaled germanium (Ge) based photodetector with tunable polarity. The photodetector is composed of a Ge Schottky barrier field effect transistor with monolithic aluminum (Al) source/drain contacts, offering plasmon assisted and polarization-resolved photodetection. The ultra-scaled Ge photodetector with a channel length of only 200 nm shows high responsivity of about R  = 424 A W -1 and a maximum polarization sensitivity ratio of TM/TE = 11., (Creative Commons Attribution license.)

With the rapid development of portable electronic devices, electric vehicles and large-scale grid energy storage devices, there is a need to enhance the specific energy density and specific power density of related electrochemical devices to meet the fast-growing requirements of energy storage. Battery-supercapacitor hybrid devices (BSHDs), combining the high-energy-density feature of batteries and the high-power-density properties of supercapacitors, have attracted mass attention in terms of energy storage. However, the electrochemical performances of cathode materials for BSHDs are severely limited by poor electrical conductivity and ion transport kinetics. As the rich redox reactions induced by transition metal compounds are able to offer high specific capacity, they are an ideal choice of cathode materials. Therefore, this paper reviews the currently advanced progress of transition metal compound-based cathodes with high-rate performance in BSHDs. We discuss some efficient strategies of enhancing the rate performance of transition metal compounds, including developing intrinsic electrode materials with high conductivity and fast ion transport; modifying materials, such as inserting defects and doping; building composite structures and 3D nano-array structures; interfacial engineering and catalytic effects. Finally, some suggestions are proposed for the potential development of cathodes for BSHDs, which may provide a reference for significant progress in the future., Competing Interests: We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (This journal is © The Royal Society of Chemistry.)

Compared with a single nanowire (NW) or NW array, the simpler preparation process of an NW network (NWN) enables it to be fabricated in large-scale, flexible, and wearable applications of photodetectors (PDs). However, the NWN behaves many microinterfaces (MIs) between NWs, seriously limiting the device performance and stability. Here, we demonstrate a welding strategy for an MAPbI 3 NWN, which enhances the crystallinity of the NWN and enhances the radial transmission of photogenerated carriers, leading to a better device performance with ultrahigh stability. Our NWN PDs fabricated by using the welding strategy showed ultrahigh performance with an on/off ratio and detectivity of 2.8 × 10 4 and 4.16 × 10 12 Jones, respectively, which are the best performance for reported metal-semiconductor-metal (MSM) perovskite NWN PDs and are comparable to those of single-NW or NW array PDs. More importantly, our unpackaged NWN PDs show ultrahigh storage stability in air with a humidity of 55-65%, and the flexible NWN PDs can enable 250 bending cycles at different bending radii and 1000 bending cycles at fixed bending radii with no performance degradation being observed. These results indicate our welding strategy is very powerful for improving the performance of the NW device with applications in the wearable field.

Perovskite photodetectors (PDs) with tunable detection wavelength have attracted extensive attention due to the potential application in the field of imaging, machine vision, and artificial intelligence. Most of the perovskite PDs focus on I- or Br-based materials due to their easy preparation techniques. However, their main photodetection capacity is situated in the visible region because of their narrower bandgap. Cl-based wide bandgap perovskites, such as CsPbCl 3 , are scarcely reported because of the bad film quality of the spin-coated Cl-based perovskite, due to the poor solubility of the precursor. Therefore, ultraviolet detection using high-quality full inorganic perovskite films, especially with high thermal stability of materials and devices, is still a big challenge. In this work, high-quality single crystal CsPbCl 3 microplatelets (MPs) synthesized by a simple space-confined growth method at low temperature for near-ultraviolet (NUV) PDs are reported. The single CsPbCl 3 MP PDs demonstrate a decent response to NUV light with a high on/off ratio of 5.6 × 10 3 and a responsivity of 0.45 A W -1 at 5 V. In addition, the dark current is as low as pA level, leading to detectivity up to 10 11 Jones. Moreover, PDs possess good stability and repeatability., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

All-inorganic metal halide perovskites have attracted great interest in recent years due to their good device performance with higher thermal stability than that of their organic-inorganic perovskite counterparts. However, the all-inorganic perovskite polycrystalline films prepared by the conventional spin-coating method possess many pinholes, nonuniform surface with many small crystals, and irregular agglomerates, limiting their device performance. Herein, we introduced a monolayer nano-polystyrene (PS) sphere confined growth method for obtaining CsPbBr3 nanonet films (NFs) with ordered nanostructures grown in the preferred (110) orientation, which is beneficial for the charge carrier transport and the light-harvesting efficiency. The (110) peak intensity of CsPbBr3 NFs increased with the increase of the diameter of the monolayer sphere, while the (001) peak intensity was suppressed greatly, indicating the more preferred (110) oriented growth. The PDs based on (110)-orientation-preferred CsPbBr3 NFs prepared by using 850 nm PS spheres showed the best performance. The best performing device displayed the biggest linear dynamic range of up to 120 dB. In addition, a responsivity of 2.84 A W-1 and a detectivity of 5.47 × 1012 Jones were also achieved.

Organic-inorganic lead halide perovskite microcrystal (MC) films are attractive candidates for fabricating high-performance large-area self-powered photodetectors (PDs) because of their lower trap state density and higher carrier mobility than their polycrystalline counterparts and more suitability of synthesizing large lateral area films than their single-crystal counterparts. Here, we report on the fabrication of self-powered all-inorganic CsPbBr 3 perovskite MC PDs with high detectivity, using a modified solution synthesis method. The MCs are up to about 10 μm in size, and the MC layer is also about 11 μm in thickness. Under 473 nm laser (100 mW) illumination, the CsPbBr 3 MC PDs show responsivity values of up to 0.172 A W -1 , detectivity values of up to 4.8 × 10 12 Jones, on/off ratios of up to 1.3 × 10 5 , and linear dynamic ranges of up to 113 dB. These performances are significantly better than those of PDs based on polycrystalline perovskite thin films and comparable with those of PDs based on perovskite single crystals.