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Deep ultraviolet (DUV) light is easily absorbed by the ozone layer. There is no interference from DUV light at ground and low altitude. Therefore, DUV detection has high applications in criminal investigation, the security monitoring of power grid, and forest fire alarm. Wide bandgap semiconductors are more suitable for nanodevices with high frequency and high reaction rate, which have wide bandgap, high electron saturation mobility, high thermal conductivity, and high breakdown strength. In this paper, the nanostructures, self-powered technologies, flexible substrates, electrical characteristics, and simulation optimization of wide bandgap semiconductors are thoroughly summarized with recent studies. The working principle, application, optimization, and technical difficulties of DUV detectors are also discussed.

CsPbCl 3 perovskite is considered a highly promising material for ultraviolet (UV) photodetectors due to its exceptional thermal stability and excellent short-wavelength light response. However, its high lattice energy and low polarizability result in extremely low solubility in conventional solvents, making the synthesis of CsPbCl 3 single crystals a significant challenge. In this study, we propose a novel thermodynamically induced crystal restructuring (TICR) process that can transform microcrystalline films (MCFs) into single crystal films (SCFs) within a short period. This method, for the first time, has successfully achieved the synthesis of centimeter-sized CsPbCl 3 SCFs and the mechanism has been explored in depth using in-situ techniques. Furthermore, we report the first instance of a CsPbCl 3 SCF UV photodiode, which exhibits a record-breaking on/off ratio of 3.32 × 10 7 and a detectivity of up to 1.15 × 10 14 Jones under 0 V bias. It demonstrates excellent response even under weak light conditions of 10 nW·cm −2 and maintains outstanding stability with almost no performance degradation after 15 months. This study provides a novel approach for the synthesis of perovskite single crystals and holds significant potential for advancing the development of high-performance optoelectronic devices.

Ultraviolet (UV) photodetectors have attracted much attention due to their important applications in many fields. Improving of the photoelectric performance of ultraviolet detectors is the key challenge. One solution is to fabricate UV photodetectors based on a wide bandgap semiconductor material—zinc oxide (ZnO). Here, ZnO nanorods with pure surface and high crystallization are prepared by laser ablation in liquid combined with hydrothermal method. The bandgap of ZnO products calculated from UV–vis reflection spectra is 3.43 eV, which means the ZnO nanorods synthesized in this work are suitable for UV detection. Moreover, Al nanoparticles with localized surface plasmon resonance (LSPR) are also prepared by laser ablation in liquid. The UV photodetector based on the ZnO nanorods and Al nanoparticles is fabricated. It is found that the photoelectric performance of ZnO-based UV photodetector is significantly increased after the addition of Al nanoparticles. The mechanism is that the LSPR happens when laser irradiated on the ZnO nanorods with Al nanoparticles, so the absorption is enhanced. Therefore, the ZnO nanorods get more light energy, which means more photo-induced carriers are generated and the current will increase.

Sn-doped Ga2O3 thin films and metal–semiconductor–metal (MSM) ultraviolet detectors were prepared using the co-sputtering method to enhance their photoelectric performance. The results revealed that Sn doping can effectively change the optical and electrical properties of thin films, greatly improving the photoelectric responsiveness of the devices. Through microstructure testing results, all of the thin film structures were determined to be monoclinic beta phase gallium oxide. At a DC power of 30 W, the thickness of the Sn-doped thin film was 430 nm, the surface roughness of the thin film was 4.94 nm, and the carrier concentration, resistivity, and mobility reached 9.72 × 1018 cm−3, 1.60 × 10−4 Ω·cm, and 45.05 cm3/Vs, respectively. The optical results show that Sn doping clearly decreases the transmission of thin films and that the bandgap can decrease to 3.91 eV. Under 30 W DC power, the photo dark current ratio of the detector can reach 101, time responses of tr = 31 s and tf = 22.83 s were obtained, and the spectral responsivity reached 19.25 A/W.

Zinc oxide (ZnO) serves as a crucial functional semiconductor with a wide direct bandgap of approximately 3.37 eV. Solvothermal reaction is commonly used in the synthesis of ZnO micro/nanostructures, given its low cost, simplicity, and easy implementation. Moreover, ZnO morphology engineering has become desirable through the alteration of minor conditions in the reaction process, particularly at room temperature. In this work, ZnO micro/nanostructures were synthesized in a solution by varying the amounts of the ammonia added at low temperatures (including room temperature). The formation of Zn 2+ complexes by ammonia in the precursor regulated the reaction rate of the morphology engineering of ZnO, which resulted in various structures, such as nanoparticles, nanosheets, microflowers, and single crystals. Finally, the obtained ZnO was used in the optoelectronic application of ultraviolet detectors.

In this study, xylitol, a common sweetener and sucrose substitute in low-calorie foods, was quantified by high-performance liquid chromatography (HPLC). During the establishment of the analytical method, three representative detection approaches, ultraviolet detector (UVD), evaporative light scattering detector, and refractive index detector, were compared and applied to determine the xylitol content in various foods distributed in Korea. The results were compared for method validation, measurement uncertainty, and applicability. As a result, HPLC-UVD showed the lowest limit of detection (0.01 mg/L) and limit of quantification (0.04 mg/L) among the three methods. It showed a low range of relative expanded uncertainty (1.12–3.98%) and could quantify xylitol in the wide range of the samples, even trace amounts of xylitol. Therefore, a total of 160 food items, including chewing gum, candy, beverage, tea, other processed products, and beverage base, were applied with three replicates by the proposed HPLC-UVD method.

Detection of solar-blind ultraviolet (SB-UV) light is important in applications like confidential communication, flame detection, and missile warning system. However, the existing SB-UV photodetectors still show low sensitivities. In this work, we demonstrate the extraordinary SB-UV detection performance of α-In 2 Se 3 phototransistors. Benefiting from the coupled semiconductor and ferroelectricity property, the phototransistor has an ultraweak detectable power of 17.85 fW, an ultrahigh gain of 1.2 × 10 6 , a responsivity of 2.6 × 10 5 A/W, a detectivity of 1.3 × 10 16 Jones and an ultralow noise-equivalent-power of 4.2 × 10 −20 W/Hz 1/2 for 275 nm light. Its performance exceeds most other UV detectors, even including commercial photomultiplier tubes and avalanche photodiodes. It can be also implemented as an optoelectronic synapse for neuromorphic computing. A 784×300×10 artificial neural network (ANN) based on this optoelectronic synapse is constructed and demonstrated with a high recognition accuracy and good noise-tolerance for the Fashion-MNIST dataset. These extraordinary features endow this phototransistor with the potential for constructing advanced SB-UV detectors and intelligent hardware.

The electrical and optical characteristics of an n -type gallium nitride (GaN)-based Schottky barrier ultraviolet (UV) detector, where a platinum (Pt) metal layer forms the anode contact, have been evaluated by means of detailed numerical simulations considering a wide range of incident light intensities. By modeling the GaN physical properties, the detector current density–voltage characteristics and spectral responsivity for different (forward and reverse) bias voltages and temperatures are presented, assuming incident optical power ranging from 0.001 W cm −2 to 1 W cm −2 . The effect of defect states in the GaN substrate is also investigated. The results show that, at room temperature and under reverse bias voltage of −300 V, the dark current density is in the limit of 2.18 × 10 −19  A cm −2 . On illumination by a 0.36- μ m UV uniform beam with intensity of 1 W cm −2 , the photocurrent significantly increased to 2.33 A cm −2 and the detector spectral responsivity reached a maximum value of 0.2 A W −1 at zero bias voltage. Deep acceptor trap states and high temperature strongly affected the spectral responsivity curve in the considered 0.2  μ m to 0.4  μ m UV spectral range.

A porous aromatic framework (PAF) is shown to be a viable sorbent for the adsorption of phenols. To overcome the difficulty of quick adsorption and enrichment by phenols from the matrix, a sorbent material consisting of porous aromatic framework magnetic nanoparticles (PAF MNPs) with a core–shell structure was fabricated by an in situ growth method. The PAF MNP sorbent was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy and other techniques. The factors affecting enrichment performance including the amount of PAF-6 MNPs, sample pH, extraction time and elution conditions were optimized. Under the optimal conditions, a method utilizing high-performance liquid chromatography with an ultraviolet detector (HPLC-UV) was developed to quantify phenols in urine. The method showed good linearity (r ≥ 0.998), good precision (RSD ≤ 9.9%, n = 6) and a low limit of detection (1.0–2.0 ng/mL, S/N = 3), with recoveries performed in urine matrix ranging from 76.7% to 113.2%. The method is simple, time-saving and sensitive. Moreover, compared with traditional mass spectrometry detection methods, this method has advantages in terms of low cost and repeatability.

Ultraviolet (UV) detectors have important applications in many fields. ZnO is an excellent semiconductor material for the preparation of UV detectors because of its large direct gap in forbidden bandwidth, its intrinsic response band in the UV region, and its high exciton binding energy. In this paper, high-performance ZnO thin films with the optically advantageous nonpolar structure were prepared by using an atomic layer deposition, and the dominant crystal plane gradually changes from the amorphous phase to the (100) crystal plane. The conventional photoconductor structure ZnO UV detector was enhanced by the surface plasmon exciton effect of Ag nanostructure. When the operating voltage is 5 V and the response light is 350 nm, there is a maximum optical responsiveness of up to 131 A/W. The UV/visible rejection ratio can reach 1824 times. When the ZnO thin film deposition thickness is 400 deposition cycles and about 72 nm, the ZnO thin film UV detector obtains the highest responsiveness (5 V, 365 nm) of 365 A/W. Comparing the photovoltaic performance of the ZnO thin-film detector with the enhanced ZnO thin-film detector and its optimal response wavelength, it is found that the enhanced ZnO thin-film detector increased the photoresponse value by about 100 times. The optimal response wavelength in the UV region is blue-shifted, and the UV-visible rejection ratio and optical response rate are significantly improved. Graphical Abstract