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Comprehensive Summary pH is an important stimuli‐responsive signal because deprotonation‐protonation process is crucial for many life functions. Photoacid is a kind of photoresponsive group that can release protons upon irradiation. This property makes invasive pH control can be replaced by noninvasive light control. However, photoacid is rare. In this work, macrocyclic calixpyridinium was found to be used as a photoacid to release protons from acidic methylene under the irradiation of a 254 nm UV lamp. When the solution of calixpyridinium−disulfonated xantphos aggregates were irradiated by a 254 nm portable UV lamp, disulfonated xantphos was able to receive the protons released from calixpyridinium. This noninvasive photocontrolled proton transfer not only replaces an invasive pH regulation but also achieves a synergistic function. The deprotonation of calixpyridinium and the protonation of disulfonated xantphos can occur simultaneously to disrupt the aggregates. Moreover, the photoresponsive disassembly is reversible by heating. This photoresponsive material was further applied as a photocontrolled release model. In addition, a dissipative assembly was successfully designed based on this photoresponsive disassembly. This study supplies a generalized strategy to construct pH‐responsive biocompatible materials with light‐control properties by using macrocyclic calixpyridinium and its matched various guests in water. [ABSTRACT FROM AUTHOR]

The conditions of application thin semiconducting ferrite NiFe2O4 films on n-InSe crystalline layered semiconductor substrates at a temperature of 623 K by the spray-pyrolysis method for the creation of photosensitive n-NiFe2O4/n-InSe heterojunctions were studied. The mechanisms of current flow through the heterojunction were established based on the temperature dependence of forward and reverse I-V characteristics. The spectral photosensitivity of the n-NiFe2O4/n-InSe heterojunction in the energy range of 1.26÷3.2 eV was analyzed. [ABSTRACT FROM AUTHOR]

Lead-free halide perovskites have attracted widespread research interest due to their excellent optoelectronic properties and environmental friendliness. As one of the bismuth iodide compounds, Cs3Bi2I9 perovskite has been extensively explored in the field of photovoltaic devices and radiation detectors due to their non-toxic lead-free components and excellent stability. In this work, we successfully grow large-sized Cs3Bi2I9 single crystals (SC) with (l 00) and (00 l) crystal exposure facets by inverse temperature crystallization method. Under 525 nm light illumination with the intensity 15 mW cm−2 and 7 V bias, the (l 00) Cs3Bi2I9 SC shows 2 times higher photocurrent, 3.6 times higher responsivity, and 2.8 times higher detectivity than the (00 l) Cs3Bi2I9 SC, respectively. Superior response time in the scale of millisecond is obtained in both (l 00) and (00 l) Cs3Bi2I9 SCs. Based on the first-principle calculation, the (l 00) SC possesses a higher charge distribution density and a wider dispersion distribution than (00 l) SC, suggesting that more electrons in the (l 00) SC can be excited in a wider range. The tighter arrangement of Cs+ and [BiI6]− octahedra in the (l 00) SC than (00 l) SC leads to the anisotropic photoelectric performance in (l 00) and (00 l) Cs3Bi2I9 SCs. Our results provide a strategy for the oriental growth of Cs3Bi2I9 SCs and the design of anisotropic optoelectronic devices with excellent performance. [ABSTRACT FROM AUTHOR]

The utilization of two-dimensional van der waals heterostructures in optoelectronic synapses allows for the integration of information processing and memory, thereby providing novel operating platforms for simulating the perceptual visual systems and developing the neuromorphic computing systems due to its contactless, highly efficient and parallel computing. Herein, we have constructed a straightforward MoS2/WS2 heterostructure optoelectronic synapse and examined its capacity to imitate synaptic behaviors under optical stimulus. The MoS2/WS2 device demonstrated several synaptic functions, such as the excitatory postsynaptic current, short-term plasticity, long-term plasticity, pairs-pulse facilitation and 'learning-experience' behavior. Moreover, the MoS2/WS2 synaptic device can achieve a wide range of photo response wavelengths, spanning from UV to visible light, as well as the conversion from short-term plasticity to long-term plasticity. Furthermore, light-induced charge transfer due to adsorption and desorption of oxygen molecules in MoS2/WS2 heterostructure can be used to explain its working mechanism. Additionally, the synaptic plasticity of MoS2/WS2 device can be controlled by adjusting the duration, power and number of the optical pulses, which renders the MoS2/WS2-based optoelectronic synaptic device extremely favorable for implementation in the perceptual visual system. [ABSTRACT FROM AUTHOR]

An ultranarrow‐band ultraviolet (UV) GaN detector with a simple device architecture is presented. The device displays an ultranarrow band response centred at 366 nm with only ≈5 nm width, a UV–visible rejection ratio of >2 × 103, and detectivity of 1.3 × 1010 Jones at room temperature. The device is tested over a wide temperature range where the maximum response is recorded at 200 K. Temperature dependence of device response is explained by considering the thermal activation of shallow donors in low‐temperature regime and the establishment of thermal equilibrium of the donor level with conduction band at elevated temperatures. Moreover, the device displays three orders UV‐to‐visible rejection ratio over a wide temperature range of 150–350 K, showing great potential for narrowband UV detection even at elevated temperatures. Conventional and pump‐probe surface photovoltage spectroscopy measurements are performed with UV and infrared lasers to identify the electronic transitions associated with the narrowband response. It is understood that carrier excitation from valance band to shallow donor level in the interfacial depletion region is responsible for the observed behavior. The results presented here demonstrate an innovative methodology for achieving a stable and high spectrum‐selective UV photodetection without involving complex device architecture. [ABSTRACT FROM AUTHOR]

The Ti3C2Tx MXene nanosheet was prepared by 40% (v/v) hydrofluoric acid etching at 20 °C for 48 h and delamination of bulk MAX Ti3AlC2 precursor material. A 2D nanomaterial MXene Ti3C2Tx as a nanofiller was introduced to polysulfone (PSulfone) matrix. MXene and PSulfone/MXene nanocomposite systems were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope, Fourier-transform infrared and thermogravimetric analysis instruments. Dielectric and electrical characterization of PSulfone/MXene nanocomposite was carried out. The electrical resistance of Ti3C2Tx MXene from measurement current (I)–voltage (V) was measured as 116 Ω. Pure PSulfone matrix exhibits typical insulator behavior, and MXene exhibits a good conductor behavior. But, when MXene was added to the pure PSulfone matrix, the resistance of the MXene/PSulfone nanocomposite increased moderately compared to that of pure MXene. In spite of the excess of surface functional groups, MXene showed surprisingly good electron transport across the surface, while in the case of PSulfone/MXene nanocomposite, the insulating behavior of PSulfone significantly reduced the electron transport of MXene. The semiconductor behavior of PSulfone/Ti3C2Tx MXene nanocomposite indicates that MXene provides efficient charge carrier transfer in the nanocomposite system. By comparing the TGA results between the PSulfone and different weight ratios of PSulfone/Ti3C2Tx MXene nanocomposites, it was determined that MXene nanosheets had a significant effect in slightly accelerating the thermal degradation of PSulfone. Optical conductivity was investigated by preparing a film of PSulfone/MXene nanocomposite on an interdigital contact. It was observed that the optical current values changed depending on the increasing illumination intensity. Considering current–voltage measurements, the photocurrent generation potential of PSulfone/MXene nanocomposite shows that it can be used in photodevice production. [ABSTRACT FROM AUTHOR]

This study examines the impact of thermal annealing on ZnO nanorods produced by vapour phase transport. Nanorods were annealed at temperatures of 300, 500, and 700 °C. It has been demonstrated through X-ray diffraction that the annealing process led to an increase in crystalline size from 34 to 51 nm, indicating improved crystallinity. The optical bandgap decreased from 3.28 to 3.22 eV as a result of defect minimization during annealing. Due to increased crystallinity and fewer defects, annealing increased the dark conductivity from 0.8 to 2 S/cm, as shown by electrical experiments. After annealing, the photosensitivity increased from 10 to 35 and the responsivity rose from 0.18 to 0.48 A/W. The quantitative results demonstrate that annealing modifies the physical properties of ZnO nanorods and improves their photodetection capabilities. [ABSTRACT FROM AUTHOR]

Traditional pesticide emulsion formulation may exert deleterious effects on the environment and even induce stress on nontarget crops in the vicinity. In this study, γ-cyclodextrin (γ-CD)-encapsulated azobenzene derivative nanovesicles were synthesized and loaded with pendimethalin to obtain pendimethalin-loaded γ-CD/azobenzene derivative nanovesicles. Upon exposure to ultraviolet irradiation or sunlight, the azobenzene derivatives are converted from the trans- to cis- configuration, leading to the dissociation of the ternary host–guest complexes, resulting in the vesicle rupture and the subsequent release of pendimethalin. Further investigations were conducted on the γ-CD/azobenzene nanovesicles. According to the release characteristics of herbicides, the release rate of pendimethalin under ultraviolet light (365 nm) or sunlight conditions reached 88.3 ± 3%, which was 4.3 times higher than that under dark conditions, demonstrating excellent photocontrolled release behavior. Pot experiments showed that the herbicidal activity of pendimethalin-loaded nanovesicles against Portulaca oleracea (L.) and Echinochloa crusgalli (L.) Beauv. at the recommended dose was comparable to that of the pendimethalin technical under illuminated conditions. Furthermore, genotoxicity experiments reveal a notable increase in the mitotic index of onion root tip cells treated with pendimethalin-loaded nanovesicles, indicating that it had minimal inhibitory effect on cell metabolism and the genotoxicity was lower than that of pendimethalin technical. Pendimethalin-loaded nanovesicles exhibited favorable stability and photoresponsive performance. These findings reveal a promising avenue for responsive material design and release modulation using such nanovesicle systems, providing insights into their potential applications in targeted pesticide delivery systems. [ABSTRACT FROM AUTHOR]

Photoresponsive drug delivery systems (PDDSs) have emerged as a promising toolbox for drug delivery, offering precise control over the site, duration, and dosage of light‐triggered medication. It allows controlled drug release, photo‐triggered targeting, diagnosis, and treatment, improving the precision and efficacy of therapies for various diseases. Despite progress in designing different PDDSs, clinical translation has been limited due to various obstacles. Herein, this review article focuses on three critical challenges of PDDSs: 1) accumulation at diseased lesions, 2) precision of light irradiation, and 3) penetration of light in tissues. Also, this article summarizes and discusses current advancements and strategies to address these challenges. Overall, it emphasizes the need to clarify the current challenges from bench to bedside and develop strategies to enhance therapeutic outcomes, increase compatibility and patient compliance, and unlock the possibilities in different clinical therapies. [ABSTRACT FROM AUTHOR]

Mid-infrared (mid-IR) photodetection is important for various applications, including biomedical diagnostics, security, chemical identification, and free-spacing optical communications. However, conventional "photon" mid-IR photodetectors require liquid nitrogen cooling (i.e., MCT). Furthermore, acquiring mid-IR spectra usually involves a complex and expensive Fourier Transform Infrared spectrometer, a tabletop instrument consisting of a meter-long interferometer and MCT detectors, which is not suitable for mobile and compact device applications. In this work, we present tunable photoresponsivity in the mid-IR wavelength in palladium diselenide (PdSe2) – molybdenum disulfide (MoS2) heterostructure field-effect transistors (FETs), operating at room temperature. Furthermore, we applied a tunable membrane cavity to modulate the Fabry–Pérot resonance to modulate the absorption spectrum of the device layer. We used a robust polyetherimide (PEI) membrane with CVD-grown graphene to electrically tune the membrane structure. For the next step, we will integrate the PdSe2-based photodetector and tunable membrane to increase detection sensitivity and spectrum tunability to realize the 'learning'-based spectroscopy. [ABSTRACT FROM AUTHOR]

Mid-infrared (mid-IR) photodetection is important for various applications, including biomedical diagnostics, security, chemical identification, and free-spacing optical communications. However, conventional "photon" mid-IR photodetectors require liquid nitrogen cooling (i.e., MCT). Furthermore, acquiring mid-IR spectra usually involves a complex and expensive Fourier Transform Infrared spectrometer, a tabletop instrument consisting of a meter-long interferometer and MCT detectors, which is not suitable for mobile and compact device applications. In this work, we present tunable photoresponsivity in the mid-IR wavelength in palladium diselenide (PdSe2) – molybdenum disulfide (MoS2) heterostructure field-effect transistors (FETs), operating at room temperature. Furthermore, we applied a tunable membrane cavity to modulate the Fabry–Pérot resonance to modulate the absorption spectrum of the device layer. We used a robust polyetherimide (PEI) membrane with CVD-grown graphene to electrically tune the membrane structure. For the next step, we will integrate the PdSe2-based photodetector and tunable membrane to increase detection sensitivity and spectrum tunability to realize the 'learning'-based spectroscopy. [ABSTRACT FROM AUTHOR]

In this study, the effects of illumination on the electronic and optoelectronic properties of Al/hydroxymethyl functionalized Zn(II)Pc/p-Si/Al photonic device have been investigated under dark and various lighting conditions. The diode's electronic parameters have been extracted from the current–voltage characteristics. It is observed that the dark current value increases when the light is illuminated on the device, and thus, the photocurrent is formed, and this result has shown that the studied device exhibits a photoconductive behavior. The photoresponse properties of the fabricated device have been examined by transient photocurrent measurements under 100 mW/cm2 illumination, and they have also been analyzed using photocapacitance and photoconductivity measurements at different frequencies (100 kHz, 500 kHz, and 1 MHz). However, the capacitance data that may occur between the poles of the produced device have also been investigated, and it is thought that the device can also be developed as a capacitor. These results confirm that the hydroxymethyl functionalized Zn(II)Pc and p-silicon semiconductor-based device can be used particularly in electro-optic and photonic applications. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenides are of great interest due to their extraordinary electrical and optical characteristics for possible optoelectronic applications like photodetectors. In the current work, MoS2 film has been deposited by a simple and economical hydrothermal route in an alkaline solution in one pot. Raman and X-ray diffraction analyses verified the growth of the dominant 1T-phase, which provides more active sites on the film. Electron microscope images exhibit the formation of long MoS2 nanowires on top of skein-like microspheres. Each microsphere is composed of curly nanosheets. A growth mechanism is suggested for the formation of the achieved morphology. The energy bandgap of the film was calculated to be around 1.72 eV, using the optical absorbance spectrum. The photosensitivity tests showed a 26% response of the fabricated photosensor toward incident light (450 nm) and confirmed that the as-grown MoS2 has high response stability. The recorded response time of 187 s and the recovery time of 210 s showed that the sample responds quickly to incident light. The obtained results showed the effect of the 1T-MoS2 phase and nanowire structure on improving the performance of photodetectors and presented a simple method for the synthesis of MoS2 films with nanowire morphology. [ABSTRACT FROM AUTHOR]

Zinc oxide is a promising material for the creation of various types of sensors, in particular UV detectors. In this work, arrays of ordered nanorods were grown by chemical vapor deposition. The effect of environmental humidity on the sensing properties of zinc oxide nanorod arrays was investigated, and a prototype UV sensor using indium as an ohmic contact was developed. UV photoresponses were measured for the samples stored in dry and wet atmospheres. The increase in sensitivity and response of the ZnO nanorod arrays was observed after prolonged exposure to a wet atmosphere. A model was proposed to explain this effect. This is due to the formation of hydroxyl groups on the surface of zinc oxide nanorods, which is confirmed by FTIR spectroscopy data. For the first time, it has been shown that after storage in a wet atmosphere, the sensory properties of the structure remain stable regardless of the ambient humidity. [ABSTRACT FROM AUTHOR]

We utilize density functional theory to explore dicarbonitrile‐polyphenyl networks overlaid on graphene as a method for manipulating the density of Li atoms in a specific assembly pattern. Ab initio molecular dynamics calculations affirm the thermal stability of the introduced systems. We scrutinized the electronic structure and optical properties of the resultant systems, illustrating a systematic modulation of optical characteristics. Our results suggest that the optical excitation frequencies of (Li‐dicarbonitrile‐polyphenyl)/G can be efficiently tuned by systematically adjusting the density of Li atoms on graphene. [ABSTRACT FROM AUTHOR]

A heterojunction interface engineering aimed at improving the performance of all‐inorganic lead halide perovskite photodetectors (PDs) is demonstrated by coupling the two‐dimensional (2D) MoS2 materials with CsPbBr3 used in the chemical vapor deposition method in situ‐grown. The MoS2 carrier extraction layer facilitates electron injection, while the large injection barrier of the CsPbBr3/MoS2 heterojunction depletion layer keeps holes in the perovskite layer, resulting in effective separation of photogenerated carriers at the heterojunction interface. Moreover, the photoluminescence quenching and lifetime shortening of the heterojunction further prove that there is a large amount of charge transfer between the CsPbBr3 and MoS2 interface. As a result, PDs based on the CsPbBr3/MoS2/interdigitated array electrodes (IDA) heterojunction exhibit remarkable performance, such as high photoresponsivity (23.4 A W−1), detectivity (1.48 × 1013 Jones), and switching ratio (1.35 × 105), all of which are an order of magnitude better than pure CsPbBr3 PDs. The heterojunction PD also presents a superior response time (0.07 ms). [ABSTRACT FROM AUTHOR]

The RuO2-doped organic polymer composite structure was used as the interface to study the photodiode properties of a Schottky structure. Some basic electrical and optoelectrical parameters of the structure interlaid with RuO2:PVC were investigated using the I–V characteristics in the dark and under definite illuminations. The values of saturation current (I0), barrier height (ΦB0) at zero-bias, ideality factor (n), series and shunt resistances (Rs and Rsh) were calculated by using different methods such as thermionic emission, Ohm's law, Cheung and Norde functions. They were found to be intensely depend on illumination levels and voltage. Forward bias I–V data were used to obtain energy-dependent profiles of interface-states (Nss) for each illumination level. Moreover, the open-circuit voltage (Voc), short circuit current (Isc), filling factor (FF), and efficiency (η) of the fabricated Schottky structure were found as 0.118 V, 6.4 μA, 46%, and 0.088% under 50 mW/cm−2, respectively. According to the findings, the RuO2:PVC organic interlayer is light-sensitive and can thus be used in optoelectronic applications, such as photodetectors and photodiodes. [ABSTRACT FROM AUTHOR]

The ultraviolet (UV) photoconduction characteristics of the ZnO nanoparticles (NPs) deposited on glass substrates have been studied as deposited and after induction of oxygen vacancy through thermal annealing in a vacuum. The morphology, structural, and optical properties of the samples have been characterized using X-ray diffraction (XRD) patterns, field emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), UV–Vis absorption, and photoluminescence spectroscopies. The results confirmed the presence of oxygen vacancies on the surface of ZnO nanostructures after annealing. The photoconductivity behavior of the annealed ZnO NP film was investigated using a two-point probe method. The results showed significant photosensitivity under UV irradiance near its bandgap. The wavelength-dependent and time-resolved photoconductivity measurements revealed a fast response to UV illumination (rise and decay durations of 4 s and 18 s, respectively) for the annealed film optimized at 380 nm, which is the wavelength corresponding to its bandgap. The improved photoresponse characteristics of the film could be attributed to the increased surface oxygen vacancy of the annealed ZnO NP film, which helps the chemisorption of oxygen molecules from ambient air. The photoconductivity properties of the ZnO NP film investigated in this study indicate their great potential for usage in photonic devices such as photodetectors. [ABSTRACT FROM AUTHOR]

In this study, we combined CdS photonic crystals with polydimethylsiloxane (PDMS) to develop a photoresponsive CdS/PDMS photonic crystal (CdS/PDMS PC) composite, which formed the photonic crystals of two different structural colors by controlling the size of the nanometer-sized CdS colloidal microsphere and realized the photoresponsive characteristics of the photonic crystals by the addition of photochromic substances. In addition, we studied the effects of the photosensitive material in the photonic crystals on their optical properties and surface features. We used a self-assembly method to periodically arrange CdS nanospheres into photonic crystal templates. The materials with high refractive index such as CdS made photonic crystals less angle-dependent and brightly colored. PDMS combined with spirooxazine is then filled in the photonic crystal matrix, and CdS/PDMS photonic crystal composites of structural red and green colors were obtained by thermal curing. Because of the photochromic effect of spirooxazine, under ultraviolet light irradiation, the photonic crystals had the original structural color and the reversible photochromic chemical color overlaid, exhibiting a mixed color. According to this principle, when irradiated with ultraviolet light, the PDMS substrate changed from colorless to blue and the photonic crystals changed from structural color mode to photochromism mode, and this change was reversible and can be repeated. The structural color of the red photonic crystals fused with the blue PDMS to become purple, and the structural color of the green photonic crystals fused with the blue PDMS to become cyan. When irradiated with visible light, photonic crystals can return to their original structure color. In this approach, we have designed a series of ultraviolet anticounterfeiting labels to expand the application of information anticounterfeiting. [ABSTRACT FROM AUTHOR]

With the rapid advancement of technology, the wettability of conventional superhydrophobic materials no longer suffice to meet the demands of practical applications. Intelligent responsive superhydrophobic materials have emerged as a highly sought‐after material in various fields. The exceptional superhydrophobicity, reversible wetting, and intelligently controllable characteristics of these materials have led to extensive applications across industries, including industry, agriculture, defense, and medicine. Therefore, the development of intelligent superhydrophobic materials with superior performance, economic practicality, enhanced sensitivity, and controllability assumes utmost importance in advancing technology worldwide. This article provides a summary of the wettability principles of superhydrophobic surfaces and the mechanisms behind intelligent responsive superhydrophobicity. Furthermore, it reviews and analyzes the recent research progress on light, electric, and magnetic responsive superhydrophobic materials, encompassing aspects such as material synthesis, modification, performance, and responses under diverse external stimuli. The article also explores the challenges associated with different types of responsive superhydrophobic materials and the unique application prospects of light, electric, and magnetic responsive superhydrophobic materials. Additionally, it outlines the future directions for the development of intelligent responsive superhydrophobic materials. [ABSTRACT FROM AUTHOR]

The fabrication of a cadmium sulfide (CdS) thin film has been carried out by the chemical bath deposition method under two different conditions, namely, without UV light (nonexposed) and with UV light (exposed). The thin films were found to be uniform, smooth, and homogenous under both growth conditions. Structural and microstructural studies were carried out to understand the mechanism of thin-film growth. Under both conditions, the CdS thin film was found to be face-centered cubic structured. The UV light-exposed CdS thin film acquired acicular or flower-like over structures embedded in the continuous thin film of CdS. The optical band gap increased for the UV light-exposed CdS thin film. In addition, the dark and light currents also increased around 6 times for the UV light-exposed thin film compared to the nonexposed UV light thin films. The highest photosensitivity for the nonexposed and exposed UV light CdS thin film device was ~ 200% and 230%, respectively. A decrease in the photocurrent was detected and probed as a result of traps and the recombination of electrons and holes. Our findings suggest that photoexcitation during chemical reactions could be used as an effective tool to modulate the growth process and, in turn, to tune the optoelectrical properties. [ABSTRACT FROM AUTHOR]

Owning a narrow bandgap, remarkable optical and electrical properties with notable stability has made cadmium telluride (CdTe) an immensely vital semiconductor to develop cutting-edge optoelectronics. Taking these properties in to account, CdTe thin film is deposited employing the chemical bath deposition (CBD) technique. The X-ray diffraction analysis of the as-deposited thin film unveiled the composite crystalline structure, incorporating cubic, hexagonal, and tetragonal phases. The energy dispersive X-ray analysis and X-ray photoelectron spectroscopy ascertained the chemical composition of CdTe thin film. Distinctive Raman peaks are detected at 141 and 167 cm−1, signifying the presence of Cd-Te bond in the deposited thin film. The comprehensive evaluation of scanning electron micrographs emphasized the firm adhesion of the film to the substrate and displayed a uniform overlay of microstructures resembling rods. The observations from atomic force microscopy unveiled uniform grain structure with topographical features of hills and valleys. The UV-Visible spectroscopic examination elucidated that the as-deposited thin films exhibits a direct optical bandgap value of 1⋅59 eV. Temperature-dependent analysis of d.c. electrical resistivity exhibited a descending pattern, substantiating thin film's semiconducting attributes. The investigation into the photoresponse attributes of the thin film is accomplished by subjecting it to a polychromatic light, green and red monochromatic light source with an intensity of 50 mW/cm² employing three different biasing voltages. The thin film demonstrated maximum photocurrent for red light source than polychromatic and green light with maximum responsivity of 59⋅4 μA/W and detectivity of 17⋅7 × 106 Jones. These findings provide valuable insights on the photoresponse behavior of CBD deposited CdTe thin film in its as-deposited form.

To improve the utilization rate of pesticides and reduce the economic losses and environmental hazards caused by pesticide loss, the self-assembly layer of poly (octadecylsiloxane) (PODS) was prepared by hydrolysis, self-assembly and polycondensation of octadecyltrichlorosilane (OTS) on the surface of rapeseed meal (RSM) with octadecyltrichlorosilane (OTS) and p-aminoazobenzene (AAB) as modifiers. At the same time, AAB with photoisomerism was attached to RSM surface to synthesize RSM-PODS/AAB pesticide carrier with photoresponsiveness. Its structure and composition were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), UV-Vis spectroscopy and contact angle measurement device. The results showed that the loading rate of modified RSM was 21.4% higher than that of original RSM, and the cumulative release rate of pinoxaden was 83% in 72 h in the dark. The cumulative release rate of RSM-PODS/AAB was 95% after UV-Vis irradiation for 4 h and 92% after sunlight irradiation for 6 h. The application results showed that RSM-PODS/AAB loaded with pesticides had good UV-Vis and sunlight controlled release performance. The light responsive lipophilic pesticide carrier could effectively control the drug release behavior through UV-Vis and sunlight response. [ABSTRACT FROM AUTHOR]

We examined the attraction of adults to six LEDs in the red flour beetles, Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae), which is widespread as a stored grain insect. In the experiment, bluish green and green were more attractive than the two UVs, blue, and red LEDs only in females. On the other hand, no difference was found in attraction among the six LEDs in males. Next, we investigated the relationship between light intensity and attractiveness. No sexual difference in attractiveness in different light intensities was found, but the strongest light intensity was more attractive than other light intensities. Finally, we investigated the relationship between light attraction and strains artificially selected for the duration of death feigning. Short-strain beetles were more attracted to UV lights than long-strain beetles. [ABSTRACT FROM AUTHOR]

Zinc oxide is a promising material for the creation of various types of sensors, in particular UV detectors. In this work, arrays of ordered nanorods were grown by chemical vapor deposition. The effect of environmental humidity on the sensing properties of zinc oxide nanorod arrays was investigated, and a prototype UV sensor using indium as an ohmic contact was developed. UV photoresponses were measured for the samples stored in dry and wet atmospheres. The increase in sensitivity and response of the ZnO nanorod arrays was observed after prolonged exposure to a wet atmosphere. A model was proposed to explain this effect. This is due to the formation of hydroxyl groups on the surface of zinc oxide nanorods, which is confirmed by FTIR spectroscopy data. For the first time, it has been shown that after storage in a wet atmosphere, the sensory properties of the structure remain stable regardless of the ambient humidity.

Seedlings of the parasitic plant genus Cuscuta (dodder) locate hosts by circumnutation, coil around the host near soil level and form a haustorium, establishing a primary parasitism beneath the canopy. Mature shoots elongating from the parasitic region parasitize other hosts on the upper surfaces of their canopy. Although parasitism by dodder is stimulated by blue and far‐red light, and inhibited by red light, the responses to light signals during the developmental stages are not comprehensively understood. Therefore, we compared the effects of different types of light on both circumnutation and parasitism by germinating seedlings and mature shoots of Cuscuta campestris. Seedlings established parasitism under blue and far‐red light, but not under red light, as has been reported repeatedly. By contrast, mature shoots exhibited coiling around the host and haustoria formation even under a red light as well as under blue and far‐red light. These findings indicate that C. campestris modified its response to red light during the transition from young seedlings to mature shoots, facilitating parasitism. Light quality did not affect the circumnutation of either seedlings or mature shoots, indicating that circumnutation and the coiling movement that leads to parasitism were regulated by different environmental signals. Summary statement: Mature shoots of dodder, unlike seedlings, can parasitize host plants under red light. This difference between developmental stages appears to be an adaptation to different light environments and indicates that the coiling movements required for parasitism are not an extension of circumnutation. [ABSTRACT FROM AUTHOR]

Phytochrome (phy) system in plants comprising a small number of phytochromes with phyA and phyB as major ones is responsible for acquiring light information in the red—far-red region of the solar spectrum. It provides optimal strategy for plant development under changing light conditions throughout all its life cycle beginning from seed germination and seedling establishment to fruiting and plant senescence. The phyA was shown to participate in the regulation of this cycle which is especially evident at its early stages. It mediates three modes of reactions—the very low and low fluence responses (VLFR and LFR) and the high irradiance responses (HIR). The phyA is the sole light receptor in the far-red spectral region responsible for plant's survival under a dense plant canopy where light is enriched with the far-red component. Its appearance is believed to be one of the main factors of plants′ successful evolution. So far, it is widely accepted that one molecular phyA species is responsible for its complex functional manifestations. In this review, the evidence of the existence of two distinct phyA types—major, light-labile and soluble phyA′ and minor, relatively light-stable and amphiphilic phyA″—is presented as what may account for the diverse modes of phyA action. [ABSTRACT FROM AUTHOR]

To achieve advanced functionalities in nanostructured MoSe2 for enhanced electrochemical charge storage and improved photosensing, here we propose an effective strategy, i.e., the substitutional doping of the heteroatom Mn. We achieve a 313% increase in specific capacitance for 6.2% of Mn doping compared to pristine MoSe2 at the scan rate of 5 mV/s in a three-electrode configuration. For a two-electrode arrangement, also superior charge-storage performance is noted. The enhanced electrode performance can be attributed to the increase of electrical conductivity arising due to an increase of electron density for the n-type nature of Mn doping realized via an X-ray photoelectron spectroscopy study and density functional theory calculation. The latter one also unveils that Mn doping introduces catalytically active sites by disrupting homogeneous charge distribution over the topology of the MoSe2 basal plane contributing to better charge-storage performance. Mn doping-induced shift in the Fermi level of MoSe2 toward the conduction band also minimizes the contact barrier height signifying its improved capabilities for a photosensor device. Additionally, Mn doping causes alleviation of the charge-recombination process resulting in increase of photocarrier separation. As a result, we observe a 187% enhancement in the photocurrent and significantly higher responsivity and detectivity for 6.2% Mn-doped MoSe2 than its pristine counterpart. Our proposed doping strategy to modulate charge storage as well as photoresponse properties demonstrates high potential for MoSe2 along with other two-dimensional transition-metal dichalcogenides in developing next-generation energy-storage and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Strain‐based complex functionalities in response to external physical stimuli are significant for the development of intelligent robotic systems. Herein, an assembly of gold nanoparticles through ligand interaction with short linker molecule 2‐picolylamine (PA) is developed. With subnanometer spacing between the nanoparticles (NPs), the network exhibits strain sensitive carrier tunneling between them. Based on these NP networks and a lithographically patterned polydimethylsiloxane (PDMS) microstructure, a multistimuli‐responsive tactile sensor is developed that effectively transduces mechanical strain to electrical responses, and can identify variable weights, detect finger touch patterns, and is ultrasensitive to vibrational movements. Physical activities such as jogging, leg movements, and sit‐to‐stand postures are identified using the system. A significantly high gauge factor of 243 ± 10 associated with the Au NP–PA network is recorded. In addition, the sensor exhibits strain‐dependent plasmonic photodetection with a responsivity of 309 mA W−1 at a tensile strain of 3.7%. The multistimuli‐responsive Au NP–PA network demonstrated here opens up new perspectives on the development of intelligent multifunctional systems. [ABSTRACT FROM AUTHOR]

All‐inorganic lead halide perovskite CsPbBr3 has received a lot of attention in the field of optoelectronic devices due to its high absorption coefficient and photoelectric conversion efficiency. Using a heterojunction as the core of a photodetector (PD) to transform the optical signal into an electrical signal compensates for the deficiencies of using a single material. Here, a simple and efficient chemical vapor deposition (CVD) method is used to fabricate a CsPbBr3/MoO3/ITO heterojunction PD with superior photoresponse properties, including photoresponsivity of 37.209 A W−1 and detectivity of 1.64 × 1012 Jones at bias voltage of 3 V. Compared with pure CsPbBr3 perovskite, the responsivity of the PD is 3.54 times as great. As a photosensitive layer, CsPbBr3 absorbs photons and releases electrons due to its high optical absorption coefficient. The introduction of MoO3 plays a role in promoting the separation and transport of photogenerated carriers of the heterojunction structure and improves device performance. This study provides groundwork facilitating the use of CVD for in situ growth of high‐performance all‐inorganic perovskite heterostructures to realize the prospect of large‐scale production of perovskite PDs. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb2Se3) is a promising candidate for photodetector applications boasting unique material benefits and remarkable optoelectronic properties. Achieving high‐performance self‐powered Sb2Se3 photodetector through a synergistic regulation of absorber layer and heterojunction interface demonstrates great potential and needs essential investigation. In this study, an effective two‐step thermodynamic/kinetic deposition technique containing sputtered and selenized Sb precursor is implemented to induce self‐assembled growth of Sb2Se3 light absorbing thin film with large crystal grains and desirable [hk1] orientation, presenting considerable thin‐film photodetector performance. Furthermore, aluminum (Al3+) cation dopant is introduced to modify the optoelectronic properties of CdS buffer layer, and further optimize the Sb2Se3/CdS (Al) heterojunction interface quality. Thanks to the suppressed carrier recombination and enhanced carrier transport kinetics, the champion Mo/Sb2Se3/CdS (Al)/ITO/Ag photodetector exhibits self‐powered and broadband characteristics, accompanied by simultaneously high responsivity of 0.9 A W−1 (at 11 nW cm−2), linear dynamic range of 120 dB, impressive ON/OFF switching ratio over 106 and signal‐to‐noise ratio of 109, record total noise determined realistic detectivity of 4.78 × 1012 Jones, and ultra‐fast response speed with rise/decay time of 24/75 ns, representing the top level for Sb2Se3‐based photodetectors. This intriguing work opens up an avenue for its self‐powered broadband photodetector applications. [ABSTRACT FROM AUTHOR]

The Cu2ZnSnS4 (CZTS) thin films are prepared by dip-coating technique. The prepared thin films showed perfect stoichiometry and phase with a tetragonal unit cell. The scanning electron microscopy of the surface and electron diffraction showed the uniform spread of the film with the presence of fringes, respectively. The fringe width matches the inter-planner spacing of the CZTS (112) major plane. The thin film showed an optical bandgap of direct nature having a value of 1.5 eV. The analysis by Raman confirmed the CZTS phase of the prepared thin film. The CZTS thin film/Ag-paste/Cu-wire combination is studied for photoresponse for three monochromatic incident photon wavelengths. The evaluated photoresponse parameters stated the as-prepared CZTS thin film has the potential for future applications. [ABSTRACT FROM AUTHOR]

Self‐powered halide perovskite X‐ray detectors have evoked busting interests because they present outstanding properties such as low power consumption, high sensitivity, and integrability without external power source. Nevertheless, existing self‐powered X‐ray detectors exhibit low sensitivity due to the insufficient charge separation and transport. Herein, a self‐powered photodetector for sensitive X‐ray and photodetection based on single‐crystalline perovskite FAPbBr3/NiOx heterostructure is demonstrated. The built‐in field of FAPbBr3/NiOx heterojunction provides a driving force for separation and transport of photoexcited carriers. Without an external power supply, the photodetector presents excellent photoresponse performance under 450 nm light illumination, including high photoresponsivity (123.6 mA W−1), good detectivity (D = 7.1 × 1011 Jones), and ultrafast response/recovery time (10/200 ns). Simultaneously, the device achieves photovoltaic effect of 0.80 V and a large mobility–lifetime product of 1.1 × 10−3 cm2 V−1, which enable a superior X‐ray sensitivity of 402 µC Gyair−1 cm−2 at zero bias voltage. These results imply that the simple combination of perovskite single crystal and a hole transporting layer provides a flexible platform for the realization of energy‐saving self‐powered photodetector in visible light and X‐rays. [ABSTRACT FROM AUTHOR]

To fabricate efficient light sensing/energy conversion devices, the interfacial defects in perovskite devices must be controlled. Herein, an organic-small-molecule intermediate layer (consisting of PDINN; N,N'-bis(3-(3-(Dimethylamino)propylaminropyl) perylene-3,4,9,10-tetracarboxylic diimide) perylene-3,4,9,10-tetracarboxylic diimide (C40H46N6O4)) is deposited between the upper electrode and intermediate layer of a sensing device. The PDI-derivative has symmetrical aliphatic amine groups at both ends. The effects of the interfacial defect cover layer on the performance of the perovskite device due to the chemical and structural specificity of PDINN are investigated. The performance characteristics are determined under different illuminance conditions. [ABSTRACT FROM AUTHOR]

The CsPbX 3 perovskites have demonstrated promising applications in the field of X-ray detection. Appropriate element doping to substitute Pb in CsPbX 3 not only improves the photoresponse performance of the resulting material but also reduces the Pb content for achieving environmental protection. Herein, X-ray detectors based on Sr-doped CsPb 1-x Sr x Br 3 thick films were developed. The effects of Sr doping concentration were investigated. The incorporation of Sr increased the density of the CsPbBr 3 thick film and modulated the bandgap of the materials. CsPb 1-x Sr x Br 3 exhibited good optical responses at different bias voltages and X-ray doses. The X-ray response improved as the Sr-doping concentration increased. Therefore, the partial substitution of Sr into CsPbBr 3 is suitable for reducing the Pb content in X-ray detectors. Furthermore, the development of CsPb 1-x Sr x Br 3 thick films provides a new strategy for the detection of X-rays. [ABSTRACT FROM AUTHOR]

A novel multi-hybrid hemicucurbituril with good solubility in organic solvent has been synthesized by combining derived glycoluril, ethyleneurea, and aromatic group in one macrocycle. This macrocycle has exhibited properties in photoresponse and derivatization, and showed obvious interaction with Fe3+ and Cu2+ by the fluorescence spectra study. The modified hemicucurbituril could be easily converted to another imidazolidine-2,4-dione-containing macrocycle. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb _2 Se _3 ), a binary semiconducting compound has widespread research attention due to its excellent optoelectronic properties in the visible region and usefulness in applications such as solar cells, photosensors and photoelectrodes. The presented study explores the thickness dependent photoresponse in Sb _2 Se _3 thin films, prepared by reactive selenization of antimony films having thickness values of ∼938 nm and ∼1879 nm when stacked second time. Growth orientation along [001] direction was achieved through carefully optimized selenization conditions to enable favourable charge transport in anisotropic Sb _2 Se _3 . Predominant Sb _2 Se _3 formation was inferred from x-ray diffraction, Raman spectroscopy, secondary electron microscopy and energy-dispersive X-ray analyses. High optical absorption coefficient values of about 1 × 10 ^5 cm ^−1 and 5.7 × 10 ^4 cm ^−1 were observed for ∼938 nm and ∼1879 nm thick Sb _2 Se _3 thin films. Further, the optoelectronic properties were elucidated through current–voltage and transient photoresponse measurements under dark and illumination conditions. The measurements were done under zero and different bias voltages. Sb _2 Se _3 films having∼ 938 nm thickness exhibited self-driven photoresponse with a responsivity of 4.3×10 ^−8 A W ^−1 and detectivity of 3.5 × 10 ^6 jones respectively, under AM 1.5 G illumination conditions.

Abstract Antimony selenide (Sb2Se3) is a promising candidate for photodetector applications boasting unique material benefits and remarkable optoelectronic properties. Achieving high‐performance self‐powered Sb2Se3 photodetector through a synergistic regulation of absorber layer and heterojunction interface demonstrates great potential and needs essential investigation. In this study, an effective two‐step thermodynamic/kinetic deposition technique containing sputtered and selenized Sb precursor is implemented to induce self‐assembled growth of Sb2Se3 light absorbing thin film with large crystal grains and desirable [hk1] orientation, presenting considerable thin‐film photodetector performance. Furthermore, aluminum (Al3+) cation dopant is introduced to modify the optoelectronic properties of CdS buffer layer, and further optimize the Sb2Se3/CdS (Al) heterojunction interface quality. Thanks to the suppressed carrier recombination and enhanced carrier transport kinetics, the champion Mo/Sb2Se3/CdS (Al)/ITO/Ag photodetector exhibits self‐powered and broadband characteristics, accompanied by simultaneously high responsivity of 0.9 A W−1 (at 11 nW cm−2), linear dynamic range of 120 dB, impressive ON/OFF switching ratio over 106 and signal‐to‐noise ratio of 109, record total noise determined realistic detectivity of 4.78 × 1012 Jones, and ultra‐fast response speed with rise/decay time of 24/75 ns, representing the top level for Sb2Se3‐based photodetectors. This intriguing work opens up an avenue for its self‐powered broadband photodetector applications.

Modern high-performance photodetector research is driven by the need to simultaneously improve multiple parameters, but also fit the decreasing size of electronics and maintain low production price. Here, we demonstrated how our synthesized ZnO tetrapod (ZnO-T) nanostructure was deposited on electrodes with variating gap by four coating methods including drop casting, microdrop casting, spray coating and slot-die coating with the same thickness. Optimizing the inter-electrode gap and coating method the record IUV/IDark ratio per unit area value of 8.73 × 106 was obtained. The fastest rise time 0.78 s and fastest decay time 0.94 s were obtained by slot-die coated sensors. High photoresponse of ZnO-Ts, the inter-electrode gap size influences formation of ZnO-T microstructure during coating process and morphology influence on photoresponse was explained. We demonstrate that even with the same optimized ZnO-T nanostructures photoresponse can be improved by 2 orders of magnitude. Our work shows the importance of coating morphology and inter-electrode gap optimization.

Abstract Self‐powered halide perovskite X‐ray detectors have evoked busting interests because they present outstanding properties such as low power consumption, high sensitivity, and integrability without external power source. Nevertheless, existing self‐powered X‐ray detectors exhibit low sensitivity due to the insufficient charge separation and transport. Herein, a self‐powered photodetector for sensitive X‐ray and photodetection based on single‐crystalline perovskite FAPbBr3/NiOx heterostructure is demonstrated. The built‐in field of FAPbBr3/NiOx heterojunction provides a driving force for separation and transport of photoexcited carriers. Without an external power supply, the photodetector presents excellent photoresponse performance under 450 nm light illumination, including high photoresponsivity (123.6 mA W−1), good detectivity (D = 7.1 × 1011 Jones), and ultrafast response/recovery time (10/200 ns). Simultaneously, the device achieves photovoltaic effect of 0.80 V and a large mobility–lifetime product of 1.1 × 10−3 cm2 V−1, which enable a superior X‐ray sensitivity of 402 µC Gyair−1 cm−2 at zero bias voltage. These results imply that the simple combination of perovskite single crystal and a hole transporting layer provides a flexible platform for the realization of energy‐saving self‐powered photodetector in visible light and X‐rays.

As a new type of inorganic‐organic hybrid semiconductor, quantum‐confined atomically precise metal nanoclusters (MNCs) have been widely applied in the fields of chemical sensing, optical imaging, biomedicine and catalysis. Herein, we successfully design and fabricate the first example of MNC‐based spin valves (SVs) that exhibit remarkable magnetoresistance (MR) value up to 1.6 % even at room temperature (300 K). The concomitant photoresponse of MNC‐based SVs unambiguously confirms that the spin‐polarized electron transmission takes place across the MNC interlayer. Furthermore, the spin‐dependent transport property of MNC‐based SVs is largely varied by changing the atomic structure of MNCs. Both experimental proofs and quantum chemistry calculations reveal that the atomic structure‐discriminative spin transport behavior is attributed to the distinct spin‐orbit coupling (SOC) effect of MNCs. [ABSTRACT FROM AUTHOR]