Light Irradiation Research Articles

Engineering of a N-Doped Anatase/Rutile TiO2 Heterophase Junction via In Situ Phase Growth for Photocatalytic Hydrogen Evolution.

N-doped anatase/rutile TiO2 (AR-N/TiO2) photocatalysts were prepared by combining the strategy of N-doping and in situ heterophase junction generation, which significantly enhanced the photocatalytic H2 generation (1.68 mmol· h-1·g-1). Under monochromatic light at 400 nm, the light exhibits an apparent quantum efficiency of 8.6%. Moreover, this AR-N/TiO2 heterophase junction demonstrates excellent long-term stability when exposed to visible light irradiation. Through the analysis of the electronic structure, the outstanding photocatalytic activity of AR-N/TiO2 can be attributed to the maximized synergetic effect between rutile and anatase for optimal rutile content (21.6%) and enhanced response to visible light due to N-doping. Additionally, the intimate interface formed by the rutile phase grown in situ from the inner core of the anatase phase establishes well-aligned bands, which promote efficient separation of photoinduced electron-hole pairs. Furthermore, the rough surface and porosity of the as-synthesized heterophase junction facilitate an enlarged specific surface area and exposure of active sites, thereby providing more adsorptive and reactive sites that enhance conversion efficiency. This research offers an alternative approach to phase engineering for developing TiO2-based heterophase junction photocatalysts toward efficient hydrogen evolution.

Green Combustion Synthesis of Copper Magnesium Vanadate (CuMgV) NPs Using Neem Extract: Its Photocatalytic and Supercapacitor Applications

ABSTRACTOrganic dyes are a substantial contribution to environmental pollution and are considered as hazardous. These compounds are widely used in various industries like textiles, food, paper, cosmetics, and printing. A cationic dye, such as Fast Blue (FB) and Congo Red (CR), is an example of organic compound with several commercial uses but dangerous for environment and human beings. Copper Magnesium Vanadate NPs (CuMgV NPs) were successfully prepared using the combustion method in which Neem extract was used as a fuel. The XRD, FTIR, and FESEM techniques were used to analyze the sample's structure and morphology. The XRD reveals monoclinic structure of the CuMgV NPs with average particle size around 30 nm. The presence of tiny particles that prefabricated to form a widely distributed, spherical shape, and size between 15 and 25 nm was observed by HRTEM microscopic investigations. The CuMgV NPs were assessed using several electrochemical techniques. In photocatalytic tests, 120 min of UV light irradiation was sufficient to achieve a 58% and 55.52% decolorization rate for the industrial pollutants CR and Fast FB dyes. CuMgV NPs were found to have a specific capacitance value of 560.5 Fg−1 at 1 Ag−1 and a retention rate of 89% after 4000 cycles. These features promote the production of NPs for energy and environmental applications and provide greater insight into the characteristics of the material.

Design of Ctenophore Ca2+-Regulated Photoprotein Berovin Capable of Being Converted into Active Protein Under Physiological Conditions: Computational and Experimental Approaches.

Here, we describe (1) the AlphaFold-based structural modeling approach to identify amino acids of the photoprotein berovin that are crucial for coelenterazine binding, and (2) the production and characterization of berovin mutants with substitutions of the identified residues regarding their effects on the ability to form an active photoprotein under physiological conditions and stability to light irradiation. The combination of mutations K90M, N107S, and W103F is demonstrated to cause a shift of optimal conditions for the conversion of apo-berovin into active photoprotein towards near-neutral pH and low ionic strength, and to reduce the sensitivity of active berovin to light. According to the berovin spatial structure model, these residues are found in close proximity to the 6-(p-hydroxy)-phenyl group of the coelenterazine peroxyanion.

Enhancing Internal Electric Field of Metal-Free Donor-Acceptor Conjugated Photocatalysts for Efficient Photocatalytic Degradation of Tetracycline and CO2 Reduction.

Constructing alternating donor-acceptor (D-A) units within g-C3N4 represents an effective strategy for enhancing photocatalytic performance through improved charge carrier separation while concurrently addressing energy shortages and facilitating wastewater remediation. Here, a series of D-A-type conjugated photocatalysts (CNBTC-X) are prepared using g-C3N4 as an acceptor unit and different masses of 5-bromo-2-thiophenecarboxaldehyde (BTC) as a donor unit by a one-step thermal polymerization. CNBTC-50 presents higher photocatalytic properties for CO2 reduction coupled with tetracycline (TC) removal than those of g-C3N4, CNBTC-10, CNBTC-30, and CNBTC-70. The introduction of the unique electron-donor-acceptor structure effectively drives the separation and transfer of photoinduced carriers while reducing the internal carrier transfer hindrance. Photocatalytic experiments reveal that the CNBTC-50 photocatalyst achieves up to 94.6% TC removal under visible light irradiation conditions. Compared with that of the pristine g-C3N4, the photocatalytic degradation reaction rate constant of CNBTC-50 is significantly increased by about 3.87 times. The study examines the influence of various reaction parameters on degradation activity, including catalyst concentration, pH, and TC concentration. Additionally, LC-MS is utilized to perform a comprehensive analysis of the intermediates and pathways involved in TC degradation. Furthermore, CNBTC-50 demonstrates remarkable photocatalytic CO2 reduction activity, achieving rates of 20.83 μmol g-1 h-1 (CO) and 9.36 μmol g-1 h-1 (CH4), which are 10.68 and 5.98 times more efficient than those of g-C3N4, respectively. This work aims to offer valuable guidance for the rational design of nonmetal D-A-structured catalysts and effectively integrates reaction systems to couple CO2 reduction with antibiotic removal.

Rapid activation of a solution-processed aluminum oxide gate dielectric through intense pulsed light irradiation.

In this study, we report rapid activation of a solution-processed aluminum oxide gate dielectric film to reduce its processing time under ambient atmosphere. Aluminum precursor films were exposed to a high energy light-pulse and completely converted into dielectric films within 30 seconds (450 pulses). The aluminum oxide gate dielectric film irradiated using intense pulsed light with 450 pulses exhibits a smooth surface and a leakage current density of less than 10-8 A cm-2 at 2 MV cm-1. Moreover, dielectric constants of the aluminum oxide layer were calculated to be approximately 7. Finally, we fabricated a solution-processed indium gallium zinc oxide thin-film transistor with AlO x using intense pulsed light irradiation, exhibiting a field-effect mobility of 2.99 cm2 V-1 s-1, threshold voltage of 0.73 V, subthreshold swing of 180 mV per decade and I on/I off ratio of 3.9 × 106.

Visible-light driven S-scheme Bi2WO6/graphitic carbon nitride heterojunction for efficient simultaneous removal of TC and Cr(VI)

The application of photocatalysts in water governance has attracted extensive attention, and past research efforts often focused on single pollutant removal. Simultaneous removal of multiple pollutants from wastewater by a single processing unit is highly desirable, realistic, and challenging. The use of band-matched semiconductors to form heterojunctions is an important way to achieve this technology. In this work, we have designed a Bi2WO6/g-C3N4 heterojunction via an in-situ growth method. The in-suit XPS was used to verify the electron transfer pathway which conforms to the S-scheme mechanism. Under visible light irradiation, the removal rates of Cr(VI) and TC are 97.7 % and 96.0 % respectively. In addition to the excellent photocatalytic performance, the catalyst showed a high degree of stability during the five cycles. The formation mechanism of S-scheme heterojunction is discussed based on DFT calculation and physicochemical characterization. Liquid chromatography-mass spectrometry (LC-MS) and Quantitative Structure-Activity Relationship (QSAR) were used to analyze and predict the degradation pathways, intermediates, and toxicity. The efficient performance of the photocatalyst is attributed to the more efficient photogenerated charge transfer efficiency brought about by the formation of the built-in electric field, and the improvement of the photogenerated carrier recombination rate to provide more reactive sites with a large specific surface area. We provide a practicable strategy for the efficient treatment of inorganic and organic co-pollutants in environmental water by constructing an S-scheme heterojunction photocatalyst.

Chiral Inorganic Polar BaTiO3/BaCO3 Nanohybrids with Spin Selection for Asymmetric Photocatalysis.

Chirality-dependent photocatalysis is an emerging domain that leverages unique chiral light-matter interactions for enabling asymmetric catalysis driven by spin polarization induced by circularly polarized light selection. Herein, we synthesize chiral inorganic polar BaTiO3/BaCO3 nanohybrids for asymmetric photocatalysis via a hydrothermal method employing chiral glucose as a structural inducer. When excited by opposite circularly polarized light, the same material exhibits significant asymmetric catalysis, while enantiomers present an opposite polarization preference. More importantly, the preferred circularly polarized light undergoes reversal with reversal of the CD signal. Systematic experimental results demonstrate that more photogenerated carriers are generated in chiral semiconductors under suitable circularly polarized light irradiation, including more spin-polarized electrons, which inhibits the recombination of electron-hole pairs and promotes the activation of oxygen molecules into reactive oxygen species, thus inducing this asymmetric photocatalytic feature. This study provides valuable insights for the development of highly efficient polarization-sensitive chiral perovskite nanostructures as promising candidates for next-generation, multifunctional chiral device applications.

Synthesis of aluminum oxide nanoparticles using seeds of Carica papaya and evaluation of it for antimicrobial, antioxidant, and photocatalysis activity

The present work is aimed at the synthesis of aluminum oxide nanoparticles (AlONPs) using the seed extract of Carica papaya. The aluminum oxide nanoparticles were evaluated using X-ray diffraction (XRD), Fourier transforms infrared (FTIR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray (EDX), ultraviolet–visible (UV–Vis) spectrophotometer, and zeta potential, respectively. This work also determines the antimicrobial and antioxidant activity of the seed extract AlONPs against pathogens such as Bacillus cereus (B. cereus), Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Salmonella enterica (S. enterica) for antibacterial and Aspergillus niger (A. niger) for antifungal. The as-synthesized AlONPs were used for the degradation of EY dye in the presence of visible light. The presence of an absorption peak at a wavelength of 272 nm in the synthesized nanoparticles was detected by UV–Vis spectroscopy analysis. The results of the FTIR study confirmed the existence of various chemicals and functional groups in the 500–4000 cm−1 range. EDX results revealed that it included 68% aluminum and 22% oxygen established the high purity of the AlONPs. The average crystallite size of the synthesized AlONPs was found to be 52 nm by XRD analysis. Using DPPH activity, the synthesized AlONPs showed incredible antioxidant properties of 72.42% inhibition at the maximum concentration of 100 µg/ml. Moreover, it was found that the AlONPs significant antibacterial activity against tested strains viz. B. cereus (20 mm) and also showed antifungal efficacy against A. niger (30 mm) at higher concentrations of AlONPs. The photocatalytic degradation of the dye through the utilization of the synthesized AlONPs was clearly evident through the observation of a shift in color of the Eosin Y dye, transitioning from a deep pink hue to a nearly colorless state after exposure to UV light for 300 min. The green synthesized AlONPs show high photocatalytic degradation of EY 91.41% after 300 min under visible light irradiation. The current investigation has demonstrated that the seed extract of Carica papaya serves as a significant resource for the synthesis of AlONPs through a biological, eco-friendly, and non-toxic approach, while also possessing antibacterial, antioxidant, and photocatalytic properties.

Efficacy of indirect intense pulsed light irradiation on meibomian gland dysfunction: a randomized controlled study.

To investigate the efficacy and mechanisms of indirect intense pulsed light (IPL) irradiation on meibomian gland dysfunction (MGD). A total of 60 MGD patients was included in this prospective randomized controlled trial. Patients were randomly assigned 1:1 into two groups (3-mm group and 10-mm group) in which IPL was applied at distances from the lower eyelid margin of 3 and 10 mm, respectively. Both groups received three times treatment with 3-week interval. Meibomian gland yield secretion score (MGYSS), standard patient evaluation of eye dryness (SPEED) questionnaire, tear break-up time (TBUT), corneal fluorescein staining (CFS), and in vivo confocal microscopy were performed at baseline and after every treatment. After three IPL treatments, both groups had significant improvement in MGYSS (both P<0.05). The non-inferiority test showed that improvement in 10-mm group was not inferior to that in 3-mm group (P<0.001). In both groups, temporal regions of both upper and lower eyelids showed significant improvement in MGYSS. Scores of SPEED questionnaire in both groups declined significantly (both P<0.001) and changes of SPEED had no difference between two groups (P=0.57). Density of central corneal subepithelial nerves and TBUTs showed no statistically significant changes. The 3-mm group had improvement on corneal fluorescein staining (P=0.048) and meibomian gland morphology (acini wall thickness P=0.003, hyperreflective points P=0.024) while the 10-mm group had not. The efficacy of IPL indirect irradiation in improving meibomian gland secretion and alleviating dry eye symptoms remains unchanged with increase in treatment distance. IPL may primarily act on the functional improvement of the meibomian glands and corneal nerves.

Qualitative and Quantitative Luminescence Detection of 2,6-Dipicolinic Acid and Levofloxacin Based on a High-Nuclearity Eu(III) Nanomolecular Sensor.

Rapid and accurate testing of 2,6-dipicolinic acid (DPA) and levofloxacin (LFX) has been attracting much attention due to the fact that the former is an important biomarker of anthrax spores and the latter is a third-generation fluoroquinolone drug and has been recognized as an important environmental pollutant. Herein, we report the preparation of a 13-metal Eu(III) nanomolecular sensor (molecular sizes: 2.0 × 2.4 × 3.2 nm) bearing a new flexible Schiff base ligand for luminescence testing of DPA and LFX with high selectivity and sensitivity. The rapid enhancement of the Eu(III) luminescence of 1 caused by DPA and LFX is expressed by fitting equation I615nm = k × [C] + a, which can be used to quantitatively detect DPA and LFX concentrations in CH3CN, fetal calf serum (FCS), and a real drug. The response times of 1 to DPA and LFX are less than ten seconds, with detection limits as low as 3.78 × 10-2 to 2.71 nM. The test strips containing 1, as well as 1@SA films, can be used to qualitatively detect DPA and LFX by the color changes under the irradiation of UV light.

Integration of horizontally acquired light-harvesting genes into an ancestral regulatory network in the cyanobacterium Acaryochloris marina MBIC11017

ABSTRACT The acquisition of new capabilities by horizontal gene transfer (HGT) shapes the distribution of traits during microbial diversification. In the Chlorophyll (Chl) d -producing cyanobacterium Acaryochloris marina , the genes involved in the production and disassembly of the light-harvesting phycobiliprotein phycocyanin (PC) were lost in the A. marina common ancestor but then subsequently regained via HGT in A. marina strain MBIC11017. However, it remains unknown how the HGT-acquired PC genes in MBIC11017 have been reintegrated into its existing regulatory network after tens of millions of years since their loss. Here, we investigated potential mechanisms of regulatory assimilation of PC genes by comparing the transcriptomes of A. marina strain MBIC11017 and a PC-lacking close relative under both low irradiance far-red light and high irradiance white light. We found that PC assembly and degradation processes have been re-assimilated into a conserved ancestral response to high light. Further, we identified putative regulatory elements that were likely co-transferred with PC genes and could be recognized by A. marina ’s pre-existing light response machinery. This study offers insights into how HGT-acquired genes can be reintegrated into an existing transcriptional regulatory network that has evolved in their absence. IMPORTANCE Horizontal gene transfer, the asymmetric movement of genetic information between donor and recipient organisms, is an important mechanism for acquiring new traits. In order for newly acquired gene content to be retained, it must be integrated into the genetic repertoire and regulatory networks of the recipient cell. In a strain of the Chlorophyll d -producing cyanobacterium Acaryochloris marina , the recent reacquisition of the genes required to produce the light-harvesting pigment phycocyanin offers a rare opportunity to understand the mechanisms underlying the regulatory assimilation of an acquired complex trait in bacteria. The significance in our research is in characterizing how an ancestrally lost, complex trait can be reintegrated into a conserved regulatory network, even after millions of years.

Photochromism in Sm3+-doped inorganic semiconductor oxide CaBiNb2O9 induced by ultraviolet light irradiation

Photochromism in Sm3+-doped inorganic semiconductor oxide CaBiNb2O9 induced by ultraviolet light irradiation

Carbon Nanotube-Phenyl Modified g-C3N4: A Visible Light Driven Efficient Charge Transfer System for Photocatalytic Degradation of Rhodamine B.

In this study, we report the synthesis and characterization of a novel photocatalyst composite composed of functionalized carbon nanotubes (f-CNT) and phenyl-modified graphitic carbon nitride (PhCN). The incorporation of the phenyl group extends the absorption range into the visible spectrum compared to pure g-C3N4. Additionally, the formation of the heterostructure in the f-CNT/PhCN composite exhibits improved charge transfer efficiency, facilitating the separation and transfer of photogenerated electron-hole pairs and reducing recombination rates. The photocatalytic performance of this composite was evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation. The f-CNT/PhCN composite exhibits remarkable efficiency in degrading RhB, achieving 60% degradation after 4 h, and 100% after 24 h under low-power white LED excitation. This represents a substantial improvement over the non-functionalized CNT/PhCN composite, which shows much lower performance. In contrast, pure PhCN demonstrates very little activity. Structural and optical properties were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman spectroscopy, and UV-Vis spectroscopy. Time-resolved photoluminescence measurements were used to study the behavior of photoexcited carriers, confirming that the composite improves charge transfer efficiency for photogenerated carriers by approximately 30%. The results indicate that the functionalization of CNTs significantly enhances the photocatalytic properties of the composite, making f-CNT/PhCN a promising candidate for environmental remediation applications, particularly in the degradation of organic pollutants in wastewater.

Вплив червоного та синього електромагнітного випромінювання на каталазну активність зародків в’юна Misgurnus fossilis L.

Photobiomodulation therapy is widely used to treat various pathological conditions. This therapy is based on the use of monochromatic light radiation. The light of the visible spectrum induces different biological effects at the molecular and cellular levels, both therapeutic and toxic. The obtained effect depends on the length of radiation, exposure, etc. One of the possible mechanisms of such influence is the regulation of pro-oxidant-antioxidant homeostasis. In order to clarify the mechanism of action of electromagnetic radiation (EMR) of different spectral composition, catalase (CAT) activity was investigated in germ cells of loach Misgurnus fossilis L. during embryogenesis. Since, loach embryos are an adequate system that reflects the physiological state of the cell both under normal conditions and as a result of the influence of various pharmacological, physical and chemical agents. The resulting zygotes were irradiated (10 min) with blue and red LEDs (λ = 460 and 660 nm, respectively). The activity of CAT was determined by the ability of hydrogen peroxi­de to form a stable colored complex with molybdenum salts. It was established that EMR of the red spectrum has the most pronounced biological effects and caused significant changes in catalase activity during embryogenesis relative to control and blue light. The maximum increase of the indicator occurs at the stage of 16 blastomeres, and at the stage of 8 and 10 divisions, a gradual decrease in enzymatic activity is observed. Irradiation by the light of the blue spectrum lasting 10 min did not cause significant changes in catalase activi­ty relative to the control at the early stages of loach embryogenesis. The obtained results suggest that CAT, one of the key enzymes of the antioxidant defense system, undergoes photoactivation under the influence of red light.

Light-dependent electron transfer mechanism on a Z-scheme MIL-100(Fe)/AgCl/Ag heterostructure for photocatalytic degradation

Research on the changes in material properties caused by different light sources and the various photocatalytic mechanisms generated is of great significance for exploring new catalysts and improving catalytic efficiency. In this study, a novel composite of MIL-100(Fe)/AgCl/Ag was synthesized for photocatalytic degradation of organic pollutants. Techniques such as ultraviolet (UV)-visible spectroscopy and surface-enhanced Raman spectroscopy (SERS) were employed to monitor the degradation process of small molecule organic pollutants in real-time under different light sources. The research found that the catalytic efficiency of the catalyst under visible light is markedly higher than that under UV light. This phenomenon can attributed to the dynamic changes in the material’s properties, particularly the adjustment of the interface electric field under different light sources. Specifically, under UV light irradiation, the catalyst follows a Z-scheme electron transfer pathway to achieve interband transitions. In contrast, under visible light irradiation, it operates through a Z-scheme electron transfer mechanism related to surface plasmon resonance (SPR), which effectively promotes separation of electrons and holes. As a results, the apparent reaction rate is approximately 2.5 times higher compared to that under UV light conditions. This study contributes to a deeper understanding of charge transfer mechanisms in photocatalytic reactions under different wavelength light sources, and could provide valuable insights for designing new light-responsive catalysts to improve their efficiency.

Two birds with one stone: Mussel-inspired anchoring strategy enabling full-spectrum utilization and superior carriers transfer capacity for efficient photocatalytic degradation and antibacterial

Antibiotic pollution that often leads to the increases in the prevalence of resistance represents unneglectable risks to human health. Photocatalysis shows great potential in addressing the antibiotic pollution issue. However, developing photocatalysts integrating full-spectrum photocatalysis and self-adaptive antibacterial performances still remains challenges due to the limited utilization rate of light and carrier transfer capacity. Herein, a mussel-inspired anchoring strategy was employed to fabricate polydopamine coated Hydrothermal carbon carbide ZIF-8ZnO (PDA@HTCC/ZIF-8ZnO) heterojunction photocatalyst. The PDA coating was used as a transition layer to promote the heterogeneous nucleation of ZIF-8 on HTCC. Benefiting from the interfacial connections formed by metal coordination interactions between catechol groups of PDA coating and metal sites of ZIF-8, the carrier transfer capacity of PDA@HTCC/ZIF-8ZnO was improved and the range of light that can be utilized for the PDA@HTCC/ZIF-8ZnO was broadened. Therefore, the PDA@HTCC/ZIF-8ZnO heterojunction presented outstanding full-spectrum photocatalytic degradation and antibacterial performances. The full-spectrum degradation efficiency of tetracycline by PDA@HTCC/ZIF-8ZnO reached 98.7 % in 50 min. Moreover, the antimicrobial efficacy of PDA@HTCC/ZIF-8ZnO against E. coli exceeded 90 % under both light and dark conditions. The promotion effect of PDA transition layer on electrons transfer has been confirmed by DFT calculations. Under light irradiation, PDA@HTCC/ZIF-8ZnO gradually degrades tetracycline through demethylation, deamination, decarboxylation reactions, and ring-opening reactions, ultimately generating CO2 and H2O. This innovative strategy benefits the future heterojunction photocatalysts design for efficient solution of antibiotics pollution and the derivative drug-resistant bacteria issues.

In Situ Fabricated Perovskite Quantum Dots: From Materials to Applications

AbstractDue to the low formation enthalpy and high defect tolerance, in situ fabricated perovskite quantum dots offer advantages such as easy fabrication and superior optical properties. This paper reviews the methodologies, functional materials of in situ fabricated perovskite quantum dots, including polymer nanocomposites, quantum dots doped glasses, mesoporous nanocomposites, quantum dots‐embedded single crystals, and electroluminescent films. This study further highlights the industrial breakthroughs of in situ fabricated perovskite quantum dots, especially the scale‐up fabrication and stability enhancement. Finally, the fundamental challenges in developing perovskite quantum dots for industrial applications are discussed, with a focus on photoinduced degradation under high‐intensity light irradiation, ion migration under electrical bias and thermal quenching at high temperature.

Enabling high-efficiency plasmon-induced visible-light-driven reduction of hexavalent chromium with Au-TiO2/Shewanella biohybrid

The application of microbe-photocatalyst biohybrid (MPB) systems to pollutant removals has drawn considerable attentions due to the high demands on energy shortage and environmental pollution prevention. However, the stability and utilization rate of photoelectrons generated under the photocatalysis of plasmonic metals are still low. Herein, we constructed a new Au-TiO2/Shewanella biohybridsystem by combining photocatalyst and electrogenic bacteria to realize the plasmon-inducedvisible-light-driven reduction of hexavalent chromium. The highly hydrophilic Au-TiO2 and the outer membrane protein (OmcA) of Shewanella were effectively complexed to form a tight composite. The irradiation of visible light increases the expression level of extracellular polymeric substances (EPS) in the MPB system and upregulates the function gene of OmcA and MtrC, suggesting that the photoelectrons are absorbed by the conductive protein and deposited into the microbes to realize high efficiency chromium removal (68.9%). This study successfully utilize the photogenerated electrons under the catalysis of plasmonic gold nanoparticles and opens up a new avenue to the application of MPB system in water treatment.

Integration of Cu2O-NiTiO3 as an efficient p-n heterojunction visible light photocatalytic system for the simultaneous removal of Cr (VI) and Alizarine Cyanine Green dye

Cu2O loaded NiTiO3 based p-n heterojunction photocatalysts of various proportions have been synthesized by liquid phase reduction process resulting in NiTiO3 nanoparticles dispersed on the surface of Cu2O. Formation of both oxide phases is confirmed from the XRD, HR-SEM and XPS analysis. Heterojunction formation is confirmed by the intimate contact between NiTiO3 and Cu2O as evidenced by HR-TEM. UV-Vis spectra exhibit a red shift indicating the extended visible light absorption. XPS shows the presence of oxidation states of Ni2+, Ti4+, Cu+, Cu2+ and O2-. Heterojunction materials showed enhanced activity for the simultaneous photocatalytic reduction of Cr (VI) and degradation of Alizarine Cyanine Green dye under visible light irradiation. 1:2 ratio of Cu2O and NiTiO3 heterojunction (1C:2N) material exhibits 100% dye degradation in 90 minutes and Cr (VI) reduction in 180 minutes. Higher activity of Cu2O-NiTiO3 p-n heterojunction is ascribed to the effective charge separation and extended visible light absorption

Self-powered solar-blind ultraviolet detectors based on the amorphous boron nitride films

Boron nitride (BN) has been a popular material in the field of ultraviolet detection because of its excellent thermal conductivity, high breakdown field strength, high absorption coefficient, and strong resistance to radiation. However, the harsh preparation conditions of its large-scale single crystal films limit the rapid development of its devices. In this work, amorphous BN films were deposited by the magnetron sputtering technique at a relatively low temperatures. On the basis of the films, the asymmetric Schottky junction solar-blind ultraviolet detectors were fabricated by the Ohmic and Schottky contact, respectively. The maximum responsivity and detectivity of the detectors are 6.4 μA/W and 2.5 × 1010 Jones under 20 V bias and 81.1 μW/cm2 ultraviolet light irradiation, respectively. More importantly, the fabricated asymmetric Schottky junction detector also achieves the stable self-powered characteristics due to the presence of its built-in electric field, and the performances are further improved after the rapid thermal annealing. The prepared BN asymmetric Schottky junction detector can operate without the need for the external power supply, which have many advantages such as simplifying the equipment structure and being able to operate in wireless. This work will provide a new reference for the design of the next generation of independent sustainable detectors.