Wavelength UV Light Research Articles

High performance Au/mix-phase MgZnO/Ga-doped ZnO/In heterojunction solar-blind UV detector with small work voltage

High performance UVC (220 nm–280 nm) detectors with low work voltage is key problem in wide application of UVC optoelectronic device. Here, Au/MgZnO/Ga-doped ZnO/In heterojunction detector is made with both high UVC sensitivity mix-phase MgZnO and high carrier density Ga-doped ZnO conductive layers. The heterostructure detector possess relative high response(0.36A/W)at 254 nm deep UV light without bias voltage. The avalanche breakdown phenomenon within the heterojunction detector, introduced high deep UV response (1390.3 A/W at 3.3 μW/cm2 230 nm) of the Au/MgZnO/Ga-doped ZnO/In heterojunction detector under 5 V bias voltage. The high response of Au/MgZnO/Ga-doped ZnO/In heterojunction detector under low work voltage, is not only much higher than MSM structure MgZnO detector under bias voltage over 25 V, but also higher than reported deep UV detector under small bias voltage. In addition, because of different internal breakdown mechanism, the peak response position of the Au/MgZnO/Ga-doped ZnO/In heterojunction detector is located at shorter wavelength position compared with MSM structure MgZnO detector. Therefore, Au/MgZnO/Ga-doped ZnO/In heterojunction detector is an ideal device structure in low voltage driven detector with relative high response at short wavelength UV light.

Physical properties of La:ZnO thin films prepared at different thicknesses using spray pyrolysis technique

Herein we investigate the impact of film thickness on the physical properties of Lanthanum (La) doped ZnO thin films. The films were fabricated using the spray pyrolysis technique with a consistent La content of 5 weight (wt) % in the initial solution. X-ray diffraction analysis indicated the presence of a hexagonal ZnO phase with preferred orientation along the (002) direction and no other phases were detected. The crystallite sizes were calculated using the Halder-Wagner equation, with a maximum size of 16.1 nm observed for a film thickness of 106 nm. Field-emission scanning electron microscopy (FE-SEM) images revealed the formation of a continuous film with an average grain size that increased as the thickness of the film increased. The grain size ranged from 74.5 to 136 nm as the film thickness varied from 106 to 426 nm. Films with lower thicknesses up to 196 nm exhibited two band gaps at approximately 3.2 and 4 eV, while films with higher thicknesses displayed a single band gap around 3.2 eV. The refractive index dispersion for all films was modeled using the Cauchy model, with parameters showing high dependence on the thickness values.The refractive index at high frequency, as calculated using the Cauchy model, was observed to decrease with increasing film thickness, ranging from 1.87 at 106nm to 1.63 at 426nm. Similar values were obtained by fitting the optical refractive index data with the Wemple-DiDomenico relation. Additionally, the UV sensing performance of the films was evaluated against UV light of a single wavelength (365 nm) at applied voltages of 10, 20, and 30V. The rise and decay times were measured, with the film thickness of 426 nm exhibiting the shortest rise and decay times at a specific applied voltage.

Improved properties of glass vials for primary packaging with atomic layer deposition

Novel pharmaceuticals and drug delivery devices may require better performance from the packaging material e.g., in terms of extractables and leachables, and unwanted interactions. To address this, we applied atomic layer deposition (ALD) to build nanometer-range SiO2, ZrO2 and Al2O3-TiO2 films on primary packaging glass. Controlled modification of the surface also enabled creation of functionality without affecting visual appearance of the material. ALD-coated Type I borosilicate vials were compared to uncoated ones, and tailored functionality was presented by appropriate measurements. The tested ALD coatings formed a barrier on glass against extractables and leachables, from the vial and the coating alike. A good ALD coating prevents any leakage into the stored drug product. Hydrolytic resistance results improved by 85–92 %, and these results correlated well with straightforward water conductivity measurements. Opposite to uncoated borosilicate glass vials, no extracted elements could be detected from the extracts of the coated vials with stable ALD films. Improved surface integrity was observed with electron microscopy as well. ALD films increased hydrophilicity of the surface and tuning the ALD film thickness and composition allowed precise blocking of UV light wavelengths, without affecting transparency. As a conclusion, ALD is a versatile method to create barrier and functional films on primary packaging materials.

Green synthesis of zinc oxide nanoparticles using Terminalia arjuna bark extract: structural, optical and photocatalytic study

Abstract Zinc oxide (ZnO) nanoparticles have been successfully synthesized by using Terminalia arjuna bark extract via a green route. Structural analysis using X-ray diffraction confirmed the prepared samples are crystalline having hexagonal wurtzite structure with space group P63 mc and average crystallite size is found to be 8.93 nm. Rietveld refinement of the data was carried out using Material Analysis Using Diffraction (MAUD) software and reliability parameters of the refinement have been obtained. Optical properties of the sample investigated by ultraviolet – visible diffuse reflectance spectroscopy reveal an absorption peak to lie at 348 nm and the direct optical band gap energy using Kubelka–Munk function is found to be 3.20 eV. Morphological investigation using scanning electron microscopy revealed that ZnO nanoparticles are nearly spherical and agglomerated. Energy-dispersive X-ray spectrometry analysis showed the presence of Zn and O only. Transmission electron microscopy imaging confirmed the predominant hexagonal structure of the prepared nanoparticles having average particles size of 9.66 nm, which is in agreement with the X-ray diffraction result. Fourier transform infrared spectroscopy was used to identify the functional groups and different vibrational modes present in the sample. The photocatalytic activity of the prepared ZnO nanoparticles was studied using methylene blue (MB) dye under a single wavelength UV light source (λ = 254 nm). The degree of degradation of MB solution was about 56 % within 120 min of illumination to UV light and the degradation reaction follows first order kinetics with rate constant 0.00434 min−1.

A Halogen‐Bonded Fluorescent Molecular Photoswitch: Transition from 3D Cubic Lattice to 1D Helical Superstructure for Polarization Inversion of Circularly Polarized Luminescence

AbstractThe fabrication of materials that can switch between circularly polarized luminescence (CPL) signals is both essential and challenging. Here, two new halogen‐bonded fluorescent molecular photoswitches, namely, HB‐switch 1 and HB‐switch 2, containing α‐cyano‐substituted diarylethene compounds with different end groups were developed. Upon exposure to specific UV or visible light wavelengths, they exhibited controllable and reversible Z/E photoisomerization. When these switches were integrated into blue‐phase liquid crystals (BPLCs), the temperature range of BP significantly expanded. Notably, the BP system incorporating HB‐switch 1 exclusively achieved reversible polarization inversion of CPL signals under irradiation with specific UV/Visible light and during cooling/heating. The photo/thermal dual‐response behavior of the CPL signals can be attributed to the phase transition from a high‐symmetry 3D BP Icubic lattice to a low‐symmetry 1D helical superstructure induced by the Z/E photoisomerization of HB‐switch 1 and temperature changes. This study underscores the significance of employing halogen‐bond assembly strategies to design materials with switchable CPL signals, opening new possibilities for CPL‐active systems.

A Halogen-Bonded Fluorescent Molecular Photoswitch: Transition from 3D Cubic Lattice to 1D Helical Superstructure for Polarization Inversion of Circularly Polarized Luminescence.

The fabrication of materials that can switch between circularly polarized luminescence (CPL) signals is both essential and challenging. Here, two new halogen-bonded fluorescent molecular photoswitches, namely, HB-switch 1 and HB-switch 2, containing α-cyano-substituted diarylethene compounds with different end groups were developed. Upon exposure to specific UV or visible light wavelengths, they exhibited controllable and reversible Z/E photoisomerization. When these switches were integrated into blue-phase liquid crystals (BPLCs), the temperature range of BP significantly expanded. Notably, the BP system incorporating HB-switch 1 exclusively achieved reversible polarization inversion of CPL signals under irradiation with specific UV/Visible light and during cooling/heating. The photo/thermal dual-response behavior of the CPL signals can be attributed to the phase transition from a high-symmetry 3D BP Icubic lattice to a low-symmetry 1D helical superstructure induced by the Z/E photoisomerization of HB-switch 1 and temperature changes. This study underscores the significance of employing halogen-bond assembly strategies to design materials with switchable CPL signals, opening new possibilities for CPL-active systems.

Far-Ultraviolet Light at 222 nm Affects Membrane Integrity in Monolayered DLD1 Colon Cancer Cells.

222 nm far-ultraviolet (F-UV) light has a bactericidal effect similar to deep-ultraviolet (D-UV) light of about a 260 nm wavelength. The cytotoxic effect of 222 nm F-UV has not been fully investigated. DLD-1 cells were cultured in a monolayer and irradiated with 222 nm F-UV or 254 nm D-UV. The cytotoxicity of the two different wavelengths of UV light was compared. Changes in cell morphology after F-UV irradiation were observed by time-lapse imaging. Differences in the staining images of DNA-binding agents Syto9 and propidium iodide (PI) and the amount of cyclobutane pyrimidine dimer (CPD) were examined after UV irradiation. F-UV was cytotoxic to the monolayer culture of DLD-1 cells in a radiant energy-dependent manner. When radiant energy was set to 30 mJ/cm2, F-UV and D-UV showed comparable cytotoxicity. DLD-1 cells began to expand immediately after 222 nm F-UV light irradiation, and many cells incorporated PI; in contrast, PI uptake was at a low level after D-UV irradiation. The amount of CPD, an indicator of DNA damage, was higher in cells irradiated with D-UV than in cells irradiated with F-UV. This study proved that D-UV induced apoptosis from DNA damage, whereas F-UV affected membrane integrity in monolayer cells.

Visible emission studies by UV light conversion in (Dy3+/Tb3+) ions pair activated zinc-bismuth-barium borotellurite glasses for achieving intense green and white light

Both white light and green emission properties of (Dy3+/Tb3+) ions pair activated zinc-bismuth-barium borotellurite glasses were studied by ultraviolet light (UV:388 and 366 nm) conversion with a focus on down-conversion process. On the dependences of Tb3+ amounts with co-doping of Dy3+, densities of glasses, excitation, emission, area of the integration in percent, decay times, multipolar interactions, and most responsible photometric parameters are investigated in the current work. These co-activated glasses show a broad color production range (450–700 nm) covering of red (∼622 nm), green (∼545 nm), and blue (∼488 nm) colors under the stimulation of UV light wavelengths. The ratio from Yellow to blue emission was analyzed to study the site symmetry of Dy3+ surrounds. With 388 nm of UV radiation, the area of the integrated intensity under the green (Tb3+:545 nm) peak reaches a maximum of 87 %, while it falls under the yellow (Dy3+:575 nm) peak at about 13 %. The decay times of co-activated glasses were found in decreasing order, followed by fitting with a double-exponential function. The Reisfeld and Dexter's energy transfer mechanism confirmed the reduction in Dy3+ emission and its lifetime values through quadrupole-quadrupole interaction (f = 10). Moreover, photometric properties such as relative color temperatures, color coordinates, and color purity were also discussed and compared to discriminate the potentiality of the present fabricated glasses for use in both white light and green-emitting devices.

Fully UV Modulated Artificial Synapses with Integrated Sensing, Storage and Computation

AbstractOptical synaptic devices are considered a preferred substitute to electrical synapses for low‐energy, high‐efficiency neuromorphic computing (NC). However, most optical synapses irreversible optical response severely restricts their application scenarios. In this study, a fully photon‐modulated synaptic device constructed from Si‐doped beta‐gallium oxide (β‐Ga2O3)/ZnO heterojunction is demonstrated. The device exhibits reversible conductance changes and mimics a range of synaptic behaviors, which are modulated by two different wavelengths (255 and 370 nm) of UV light. Owing to the device's plasticity, four types of logic functions including “AND”, “OR”, “NOR” and “NAND” are implemented in the device by optical stimulation. Furthermore, an artificial neural network (ANN) is simulated based on the device's excitatory and inhibitory characteristics, and an optical programming scheme is employed to enhance the network's performance, resulting in a high recognition rate of 95.5% for handwritten digits. The fully photon‐modulated synapse development strategy and programming scheme, as presented in this work, advance the utilization of optical artificial synapses in ANN.

Surface plasmon resonance effects of Ag@ZnO core–shell nanostructure in UV and visible light for photodiode applications

AbstractHerein, Ag@ZnO core–shell nanostructures were prepared via the wet chemical method and were then dissolved in methanol and drop cast onto a p–Si wafer. Experimental current–voltage measurements of the Ag@ZnO/p–Si heterojunction device were investigated under both visible and UV illumination of 365 and 395 nm. The photocurrent, responsivity, detectivity, and on/off ratio were found to be dependent on the light intensity of visible light and wavelength of UV light. The low photocurrent at low light intensities and its rapid increase at high light intensities was attributed to the recombination of electrons and holes and also to the presence of traps at low light intensities. The responsivity and detectivity of the photodiode reach 1.32 A/W and 5.47 × 1011 Jones, respectively at 365 nm. On the contrary, the high performance under UV light was explained by the surface plasmon resonance between Ag and ZnO.

Catalytic Oxidation-like Nuclear Nano-fusion; Fractal Involving of Room Temperature Magnetically Induced μ-Catalyzed Fusion

The nuclear fusion reaction can be catalyzed in a suitable fusion fuel by muons (heavy electrons). “For the fractal relations, ranging from DNA knots to solar neutrino flux signals”, ever derived of scale-invariant properties distinguished between classical invariant theory & quantum invariant theory subfactors. Accompanying isomorphic & Connes FusionTensor Product retrieved to μ-catalyzed fusion where surroundings of room temperature fusion driven by the balance in mtDNA fusion & fission. On behalf of the nanometer dimension of the radius of heavy electrons & wavelength of UV-light, it assumed that muons can be produced by oxidation-like decay when UV-light impinging water.

Influence of UV nail lamps radiation on human keratinocytes viability

Ultraviolet nail lamps are becoming increasingly popular, however, the safety of their use remains controversial. The following article directly responds to recently published literature data and aims to determine the viability of human keratinocytes irradiated by a UV nail-drying machine. Cells were exposed to 365–405 nm wavelength UV light emitted by a nail drying machine in two time variants: 4 and 20 min, with and without sunscreen cream SPF50 protection, and compared to the untreated control. Compared to the control, cell viability after irradiation for 4 min decreased insignificantly (p < 0.1), however for 20 min decreased by 35% (p < 0.0001). Furthermore, cells with sunscreen protection compared to those without showed significantly increased viability, regardless of time-variant (p < 0.0001). The study shows that 4-min irradiation does not significantly reduce the viability of human keratinocytes and the time of 20 min significantly alters the research results compared to 4 min, which corresponds to real conditions. The results suggest that typical manicure exposure time does not significantly affect keratinocyte viability, which could increase the risk of developing skin cancers. Despite the above results, it is recommended to use sunscreen protection on your hands during the procedure, which significantly increases the viability of keratinocytes during ultraviolet nail lamp radiation.

Optimizing radical yield from free chlorine with tailored UV light emitting diode emission spectra

Novel UV sources, which do not contain mercury, provide the opportunity for enhancement of current oxidation technologies through spectral optimization, minimizing inefficiencies that currently limit conventional technology. Wastewater reuse is the primary full-scale application of UV advanced oxidation processes (AOPs) in practice but any background absorbance and the low molar absorption by conventional radical promoters (hydrogen peroxide) have historically limited their system efficiency, resulting in the underutilization of photons in a reactor. This bench-scale research evaluated use of longer wavelength UV light emitting diodes (265, 280, and 300 nm) matched with free chlorine to optimize the utilization of photons for advanced oxidation. Free chlorine possesses large absorption bands in the 280 to 300 nm range in basic pH waters which are common in carbon-based reuse and was used to experimentally verify quantum yields of hydroxyl radical generation across the UV LED peak emission wavelengths. pH- and wavelength-dependent fluence-based rate constants were experimentally derived using Nitrobenzene and Benzoic acid as probe compounds and evaluated to determine the contribution of the hydroxyl and chlorine radical. Reclaimed water taken from various advanced treatment steps was treated with this UV LED AOP to investigate how background absorbance affects radical generation and contaminant transformation kinetics. In addition, alternative performance metrics to evaluate hydroxyl radical production at different incident fluence rates and different rates of photon absorption at unique wavelengths across varying background UV absorbance levels were assessed.

Controlled Growth of Perovskite Nanocrystals on Nanotubes via a Nanoseeding Intermediate Stage: Toward Novel Optoelectronic Applications.

CsPbBr3 perovskite nanocrystals (CNCs) were densely anchored on multiwalled carbon nanotubes (MWNTs) via a nanoseeding intermediate stage, in which lead-based nuclei are formed on the nanotube surface. After the formation of the intermediate, a cesium precursor was added to promote the growth of CNCs from the surface nuclei and to thereby obtain CNC-decorated MWNT nanohybrids (CMNHs). The morphology and properties of the CMNHs were determined by the reaction temperature employed during their synthesis. Importantly, the use of MWNTs promoted the formation of larger CNCs that emitted intense green light and modified the electronic structure and bandgap energy of the CNCs. Consequently, the CMNHs could function as optoelectronic transducers and exhibit a "turn-on" photocurrent response when exposed to UV light of narrow specific-range wavelengths. In a novel approach for preventing counterfeit products, the CMNHs were used as a light-emitting black ink to create quick-response codes with fake pixels.

Optimum Choice of Randomly Oriented Carbon Nanotube Networks for UV-Assisted Gas Sensing Applications.

We investigated the noise and photoresponse characteristics of various optical transparencies of nanotube networks to identify an optimal randomly oriented network of carbon nanotube (CNT)-based devices for UV-assisted gas sensing applications. Our investigation reveals that all of the studied devices demonstrate negative photoconductivity upon exposure to UV light. Our studies confirm the effect of UV irradiation on the electrical properties of CNT networks and the increased photoresponse with decreasing UV light wavelength. We also extend our analysis to explore the low-frequency noise properties of different nanotube network transparencies. Our findings indicate that devices with higher nanotube network transparencies exhibit lower noise levels. We conduct additional measurements of noise and resistance in an ethanol and acetone gas environment, demonstrating the high sensitivity of higher-transparent (lower-density) nanotube networks. Overall, our results indicate that lower-density nanotube networks hold significant promise as a viable choice for UV-assisted gas sensing applications.

The Mutating Effect of Microwave Irradiation on Spores and Crystal Protein Formation of Iraqi Bacillus thuringiensis kurstaki KS3

Alkhafaji, K.A., F.H. Nahar, S.A. Khlaywi, M.A. Abedallah, A.J. Feaath, A.A. Mezban. and S.A. Saleh. 2023. The Mutating Effect of Microwave Irradiation on Spores and Crystal Protein Formation of Iraqi Bacillus thuringiensis kurstaki KS3. Arab Journal of Plant Protection, 41(3): 285-291. https://doi.org/10.22268/AJPP-041.3.285291 Bacillus thuringiensis is the most important biological control agent that is used in fields and stores against insect pests of agricultural importance. This research was conducted to study the effect of microwave radiation on sporogenesis and crystal protein production by the Iraqi bacterium B. thuringiensis KS3 strain. The bacterium was enriched by Lauria bertani broth (LB) pH 7.0 for spore formation. Spore suspension was microwave irradiated at 1000 Watt for 5, 10 and 15 seconds. Spore inactivation rate for each time period of microwave treatment was calculated and the macroscopic differences were examined. Crystal protein and spore production were estimated for irradiated and nonirradiated bacterial cultures. Viable spores in the control treatment was 3×108 viable spores/ml, and decreased after 5, 10, and 15 s of microwave treatment to 3×107 , 2×106 and 2×104 viable spores/ml, respectively. The reduction of spore viability reached to 49.263% 15 seconds after treatment. The appearance of colonies on the top of nutrient agar (NA) were almost similar with the control, with no differences in color, margin and surface of treated colonies following the three time periods treatment. Colonies with dense color, smaller in size and with straight margin appeared on congo red culture for all treatments in contrast to the control. Microscopic examination showed that treated bacilli were similar regarding their shape, diameter and arrangement, however,smaller bacterial cell size following 15 s irradiation treatment was observed. Control culture after 72 h started to form spores, whereas after 24 h, irradiated spores for 5, 10 and 15 s formed 75, 90 and 90% viable spores, respectively. Crystal protein reached the highest concentration after 72 h in control culture, whereas it varied based on treatment period. The production of viable spores from microwave irradiated isolates increased about one logarithmic cycle compared with the control culture of B. thuringiensis KS3.The peak of the UV spectrum of Crystal protein extracts was recognized at 255-280 nm and the peak of the curve indicated the protein concentration at a given wavelength. Differences were recognized in the UV light wavelength range of 220-235 nm. Keywords: Sporogenesis, Physical effect, Delta toxin.

Enhancing the bio-prospective of microalgae by different light systems and photoperiods.

Microalgae are a source of highly valuable bioactive metabolites and a high-potential feedstock for environmentally friendly and sustainable biofuel production. Recent research has shown that microalgae benefit the environment using less water than conventional crops while increasing oxygen production and lowering CO2 emissions. Microalgae are an excellent source of value-added compounds, such as proteins, pigments, lipids, and polysaccharides, as well as a high-potential feedstock for environmentally friendly and sustainable biofuel production. Various factors, such as nutrient concentration, temperature, light, pH, and cultivation method, effect the biomass cultivation and accumulation of high-value-added compounds in microalgae. Among the aforementioned factors, light is a key and essential factor for microalgae growth. Since photoautotrophic microalgae rely on light to absorb energy and transform it into chemical energy, light has a significant impact on algal growth. During micro-algal culture, spectral quality may be tailored to improve biomass composition for use in downstream bio-refineries and boost production. The light regime, which includes changes in intensity and photoperiod, has an impact on the growth and metabolic composition of microalgae. In this review, we investigate the effects of red, blue, and UV light wavelengths, different photoperiod, and different lighting systems on micro-algal growth and their valuable compounds. It also focuses on different micro-algal growth, photosynthesis systems, cultivation methods, and current market shares.

Synthesis of two novel fluorescein appended dipyromethanes (DPMs): Naked-eye chemosensors for fluoride, acetate and phosphate anions

Two novel fluorescein based dipyromethane probes DPM1 and DPM2 were constructed from a simple and easily accessible fluorescein dye, and were fully characterized by means of standard spectroscopic techniques. Studies of the DPM1 and DPM2, investigated using UV–vis spectroscopy with different anions in CH3CN/DMSO, displayed selective colorimetric sensing towards fluoride, acetate and phosphate anions. Moreover, the fluorescence analysis was also accomplished with DPM1/DPM2, revealing the enhancement in the emission spectra of the fluoride, acetate and phosphate anions. From the studies, we noticed that the DPM1/DPM2 having spirolactone ring is non-fluorescent, which upon addition of the fluoride, phosphate and acetate, underwent ring-opening, resulting in the generation of strong fluorescence. The solid state images divulges that DPM1 shows green fluorescence and DPM2 displayed dark green fluorescence upon irradiating with UV-light of wavelength 254 nm. We infer that such types of naked eye sensors might reveal the potential applications in the selective and sensitive detection of fluoride/acetate/phosphate, and/or other biologically significant anions in nearby future.

Eco-Friendly Photoreversible Adhesives Derived from Coumarin-Functionalized Epoxy Soybean Oil

The increasing demand for high-performance thermosetting adhesive materials is causing the continuous depletion of fossil reserves and has led to environmental pollution by accumulating recalcitrant plastic waste as thermosetting polymer networks are hard to recycle or reuse. This is particularly true in the case of their use as adhesives, where not only can a crosslinked adhesive not be recovered but multi-material components and devices can be difficult to readily separate, making reuse and recycling complex. Bio-based feedstocks and reusable polymeric materials can start to address these issues and reduce their environmental impact. In this work, we developed sustainable green adhesives which are reversible in architecture (changing from thermoset to non-crosslinked material) by combining bio-renewable epoxidized soybean oil (ESO) and non-toxic coumarins, which can readily undergo reversible [2 + 2] cycloaddition reaction under the appropriate wavelength of UV light. A series of coumarin-modified ESO materials were synthesized and chemically characterized by 1H NMR, 13C NMR, Fourier-transform infrared (FTIR) spectroscopy, and gel permeation chromatography. The extent and kinetics of the polymerization of all systems were monitored and calculated using UV–visible spectroscopy. The photoreversibility of these synthesized polymer networks was also chemically investigated and quantified with UV–visible spectroscopy and FTIR techniques. The physical properties of the materials were tested as well as their ability to heal defects such as scratches on the surface when stimulated by the appropriate UV light. Systems with a more flexible coumarin arm showed a superior adhesion strength with a measurable lap shear strength of 3.1 MPa with a minimum of 0.045 J cm–2 dose of 365 nm UV irradiation and with an excellent reuse efficiency of 94%.

Enhanced UV photo-detection properties of graphene oxide incorporated transparent TiO2 thin films in Schottky configuration

Here we report the modification of UV photo-response characteristics of solution processed transparent titanium dioxide-graphene oxide (TiO2-GO) nanocomposite thin films measured in metal-semiconductor (MS) Schottky junction configuration with the variation of GO content. Optical characterizations confirm the GO induced modification of optical band gap of TiO2 thin films of average thickness ∼100 nm without compromising the transparency in the visible range of electromagnetic spectrum. The nonlinear current-voltage characteristics with rectifying nature for TiO2-GO nanocomposite thin films with silver electrode indicate the formation of MS Schottky junction. The UV response characteristics like photocurrent, photo response times of the fabricated MS junctions improve significantly with the GO content in host TiO2 matrix when measured under UV light of wavelength ∼365 nm. The enhanced photocurrent (Iph) with reduced rise (tON) and recovery time (tOFF) of photo response is attributed to the GO induced modification of space charge region, passivation of interface defect states for betterment of charge carrier transport and less recombination of photo-generated charge carriers. Impedance spectra measured for nanocomposite thin films under dark and illumination confirm the modification of grain-boundary/interface to enhance the charge transport mechanism.