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oe1(光电查) - 科学论文

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出版时间
  • 2018
研究主题
  • imgae sensor
  • internet of things
  • drone
  • visible light ID
  • Signal-to-Noise Ratio (SNR)
  • Infinite Gain Multiple Feedback (IGMF)
  • Visible Light Communications (VLC)
  • LED
  • Trans-Impedance Amplifier (TIA)
应用领域
  • Optoelectronic Information Science and Engineering
机构单位
  • Tohoku University
  • University of Northumbria
  • University of Huddersfield
645 条数据
?? 中文（中国） ▾

  • Photoelectrochemical Gas–Electrolyte–Solid Phase Boundary for Hydrogen Production From Water Vapor

    摘要： Hydrogen production from humidity in the ambient air reduces the maintenance costs for sustainable solar-driven water splitting. We report a gas-diffusion porous photoelectrode consisting of tungsten trioxide (WO3) nanoparticles coated with a proton-conducting polymer electrolyte thin film for visible-light-driven photoelectrochemical water vapor splitting. The gas–electrolyte–solid triple phase boundary enhanced not only the incident photon-to-current conversion efficiency (IPCE) of the WO3 photoanode but also the Faraday efficiency (FE) of oxygen evolution in the gas-phase water oxidation process. The IPCE was 7.5% at an applied voltage of 1.2 V under 453 nm blue light irradiation. The FE of hydrogen evolution in the proton exchange membrane photoelectrochemical cell was close to 100%, and the produced hydrogen was separated from the photoanode reaction by the membrane. A comparison of the gas-phase photoelectrochemical reaction with that in liquid-phase aqueous media confirmed the importance of the triple phase boundary for realizing water vapor splitting.

    关键词： proton exchange membrane,solar H2 production,tungsten oxide photoanode,visible-light-driven photoelectrode,gas-phase water splitting

    更新于2025-09-09 09:28:46

  • Tripyridine-Derivatives-Derived Semiconducting Iodo-argentate/cuprate Hybrids with Excellent Visible-light Induced Photocatalytic Performance

    摘要： Through regulating the pH values, a series of iodo-argentate/cuprate hybrids, [Me3(4-TPT)]4[Ag6I18] (1, Me3(4-TPT) = N,N’,N’’-trimethyl-2,4,6-tris(4-pyridyl)-1,3,5-triazine), [Me3(4-TPT)][M5I8] (M=Ag/2, Cu/2a), [Me3(3-TPT)][M5I8] (Me3(3-TPT) = N,N’,N’’-trimethyl-2,4,6-tris(3-pyridyl)-1,3,5-triazine, M=Ag/3, Cu/4), exhibit adjustable structural variations with different dimensional structures, have been obtained under solvothermal conditions. They are directed by two types of in situ N-alkylation TPT-derivatives (Me3(4-TPT) for 1/2/2a and Me3(3-TPT) for 3/4) and represent the isolated units (1), 1-D polymeric chain (4), 2-D layered structures (2/2a, 3) based on diverse metal iodide clusters. These compounds possess reducing band gaps comparing with the bulk β-AgI and CuI and belong to potential semiconductor materials. Iodocuprates feature highly efficient photocatalytic activity in sunlight-induced degradation of organic dyes. The detailed study on the possible photocatalytic mechanism, including the radical trapping tests and theoretical calculations, reveals that the N-alkylation TPT moieties contribute to the narrow semiconducting behavior and effectively inhibit the recombination of photogenerated electron–hole pairs, which result in an excellent visible-light induced photocatalytic performance.

    关键词： visible-light-driven,photocatalysis,structural variations,inorganic–organic hybrid metal halides,polypyridine-derivatives

    更新于2025-09-09 09:28:46

  • Novel photocatalyst nitrogen-doped simonkolleite Zn5(OH)8Cl2·H2O with vis-up-conversion photoluminescence and effective visible-light photocatalysis

    摘要： As photocatalysts exhibit selectivity toward various pollutants, it is necessary to develop different and novel photocatalysts. In this work, a novel photocatalyst-nitrogen-doped simonkolleite Zn5(OH)8Cl2·H2O (DSM) is prepared through a new facile method: calcinating the mixture of zinc hydroxide, urea, and guanidine hydrochloride at 575?°C for 1?h in a furnace with an air atmosphere. The as-prepared sample was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL) spectra, UV–visble near-infrared diffuse reflection spectra (UV–Vis–NIR DRS), Brunauer–Emmett–Teller (BET) method, Ramen spectra and Zeta potential measurement, photocatalytic properties, as well as active species trapping experiments. XRD and XPS show the as-prepared powder is nitrogen-doped simonkolleite Zn5(OH)8Cl2H2O (DSM) with a small ZnCl2 fraction. SEM investigation indicates that the as-prepared powder possesses a flower-like layered shape. The UV–Vis–NIR exhibits that after doping, the DSM possesses strong light absorption in the ranges of 300–500 and 1400–2500?nm, a direct electronic transition with a band gap energy of 2.469?eV. PL measurement reveals a strong photoluminescence and an up-conversion from lower to higher-energy visible light in as-prepared samples. Zeta potential investigations show that during photocatalysis, the charges on as-prepared photocatalyst are positive. The photocatalytic experiments show a good dark adsorption, a high photodegradation (99.4% at 60?min), a high pseudo-first-order constant (k) of 0.0261?min?1. Meanwhile, the active species trapping experiments suggest that hole (h+) is the dominant active species during photocatalysis. It is concluded that the doping favors in enhancing vis-light-photocatalysis. This work makes a significant contribution to the literature.

    关键词： photocatalyst,nitrogen-doped simonkolleite,visible-light photocatalysis,photoluminescence

    更新于2025-09-09 09:28:46

  • Vis-NIR spectroscopy Combined with Wavelengths Selection by PSO Optimization Algorithm for Simultaneous Determination of Four Quality Parameters and Classification of Soy Sauce

    摘要： The performance of Vis-NIR techniques combined with variable select by a simple modified particle swarm optimization (PSO) algorithm for the determination of four quality parameters in soy sauce was evaluated. Compared with full-spectral support vector machine regression (Full-SVMR) and SVMR based on competitive adaptive reweighted sampling (CARS-SVM) method, the application of PSO wavelength selection provided a notably improved SVM regression model. The root-mean-square error of amino acid nitrogen, salt, total acid content, and color ratio obtained by PSO-SVMR are 0.0075 g/100 ml, 0.2176 g/100 ml, 0.0077 g/100 ml, and 0.0506 in predicted sets, respectively. The correlation coefficients of predicted sets obtained by PSO-SVMR reached 0.9997, 0.9462, 0.9996, and 0.9998, respectively. Meanwhile, a classification study constructed with principal component analysis and SVM classification model based on the feature wavelengths selected by PSO shows that Vis-NIR spectra can be used to classify soy sauce according to their brands and quality. The result showed that the Vis-NIR spectroscopy technique based on PSO wavelength selection has high potential to predict the quality parameters in a nondestructive way. This analytical tool may also contribute to the detection of fraud and mislabeling in the soy sauce market and certainly contribute to improvement in quality and reliability of the soy sauce market.

    关键词： Quality parameters,Wavelength selection,Modified particle swarm optimization algorithm,Visible and near-infrared spectroscopy,Soy sauce

    更新于2025-09-09 09:28:46

  • Degradation study of malachite green on chitosan films containing heterojunctions of melon/TiO2 absorbing visible-light in solid-gas interfaces

    摘要： Urea modified TiO2 nanoparticles were synthesized at different TiO2: urea ratios (10, 30 and 60 (%wt) named UTiO2-10, 30 and 60) by sol-gel method and annealing at 400 °C during 1h. Characterization revealed the presence of TiO2 nanoparticles with visible light absorption (between 400 and 500 nm) probably due by the formation of thermolysis urea byproducts such as melon, which may induce a TiO2/melon heterojunction. Then, modified nanoparticles were immobilized on chitosan films by adding 30% (70QS/30UTiO2) and 50% 50QS/50UTiO2) of UTiO2 nanoparticles. Functionalized films were characterized by SEM-EDS, DRS and AFM. Photo-induced degradation of malachite green stains was evaluated on these films under different wavelengths. Upon UV-A+visible light irradiation, films showed good activity even slightly better than those containing Evonik P-25 (70QS/30P-25). Upon visible light between 450 and 800 nm, films evidenced a satisfactory performance but slower than under UV-A+visible light irradiation whereas the photobleaching activity of 70QS/30P-25 was very poor. When visible light irradiation with wavelengths higher than 590 nm was used, a slight photobleaching was also observed. DRS spectra taken at different irradiation times showed that dye underwent N-demethylated oxidative reactions either upon UV-Visible or visible light irradiation. ATR-FTIR measurements revealed the generation of benzophenones after 6 h of irradiation probably suggesting the formation of singlet oxygen under visible light. 70QS/30UTiO2-10 films showed a good photo-bleaching activity after 18 h of continuous UV-A+visible light irradiation.

    关键词： urea,Visible-light responsive TiO2,chitosan films,melon/TiO2 heterojunction

    更新于2025-09-09 09:28:46

  • Enhanced visible-light photocatalytic activity of ZnS/BiOBr/graphene oxide ternary composite

    摘要： In this paper, a facile and highly efficient ternary composite ZnS/BiOBr/Graphene oxide (ZnS/BiOBr/GO) with zinc vacancies was successfully synthesized by solvothermal method. The photocatalysts showed an efficient photocatalytic performance for organic pollutant under visible light irradiation. The photocatalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), UV-visible diffuse reflectance spectrophotometer (DRS), and photoluminescence spectroscopy (PL). The experimental results indicated that the 100 mg ZnS and 6 mg GO co-doped BiOBr (100ZBG-6) shows the highest photocatalytic activity, achieving 86.6% degradation efficiency for Rhodamine B (RhB) under visible light irradiation, which was 28.7 and 6.1 times than that of pure ZnS and BiOBr. It is indicated that the ZnS/BiOBr/GO composite has the great potential application in the degradation organic pollutant. This article describes the enhancement of light absorption and photocatalytic activity by synthesizing zinc vacancies of ZnS and introducing GO modified BiOBr.

    关键词： Zinc vacancies,ZnS/BiOBr/Graphene oxide,Organic pollutant,Photocatalytic activity,Visible light

    更新于2025-09-09 09:28:46

  • doping

    摘要： Results obtained on the visible light mediated photocatalytic properties of Al2O3 nanoparticles doped with Zn2+ ions synthesized by precipitation method is given in this paper. XRD, SEM, TEM, XPS, FT-IR and PL studies were performed to bring out the properties of the synthesized nanoparticles. Peaks related to monoclinic Al2O3 (θ -phase) was observed from the XRD patterns of the undoped and doped samples. A decrement of band gap from 3.86 eV to 3.71 eV with Zn doping has been observed. Oxygen vacancy related peaks were observed in the PL spectra of the samples. Enhanced degradation efficiency through Zn-doping has been observed for the Al2O3 nanoparticles against methyl orange. The maximum degradation efficiency of 90.69% observed for the 4 wt% Zn-doped Al2O3 catalyst was well acknowledged from its maximum degradation rate constant of 0.0273 min?1. The more stable nature of the Zn-doped Al2O3 photocatalysts confirmed their use as efficient photocatalysts for practical applications.

    关键词： Photoluminescence,Doping,Photocatalyst,Visible light

    更新于2025-09-09 09:28:46

  • Joint data transmission and dimming control optimization for MIMO-VLC systems with channel-adaptive spatial constellation design

    摘要： In the field of indoor wireless communications, visible light communications (VLCs) have attracted great attention for synergistically providing both illumination and data transmission. Meanwhile, multiple-input multiple-output (MIMO) technique has been applied in VLC systems to boost data rate by utilizing spatial resources. However, different geometrical locations of transceivers provide distinct optical channels which may effect the performance of the conventional MIMO-VLC techniques severely. In this paper, we propose the channel-adaptive spatial constellation (CASC) design for the MIMO-VLC systems by fully taking advantage of the channel state information (CSI), where the optimal transmitted signal constellation can be constructed via maximizing the minimum Euclidean distance (MED) of the received signal constellation. Meanwhile, the practical lighting constraints are taken into consideration with the non-linearity characteristic of light-emitting diode (LED) and the dimming requirements to maintain a specific indoor illumination level. Finally, simulations results indicate that the proposed CASC design can achieve significant improvement of error performance compared with the conventional MIMO-VLC schemes.

    关键词： channel-adaptive spatial constellation (CASC),dimming control,multiple-input multiple-output (MIMO),minimum Euclidean distance (MED),visible light communication (VLC)

    更新于2025-09-09 09:28:46

  • Novel photocatalytic system Fe-complex/TiO2 for efficient degradation of phenol and norfloxacin in water

    摘要： Photocatalysis is one of the effective strategies to eliminate various organic pollutants in water body. In this paper we have prepared a series of new composite photocatalysts to degrade phenol and norfloxacin under visible light irradiation. They were [FeII(dpbpy)2(H2O)2]/TiO2, [FeII(dpbpy)(phen)2]/TiO2 and [FeII(dpbpy)(bpy)2]/TiO2 (dpbpy: 2,2′-bipyridine-4,4′-diphosphoric acid, phen: 1,10-phenanthroline, bpy: 2,2-bipyridyl). The results show that their photocatalytic performance and cyclic stability are much better than that of pure TiO2 or P25. Phenol can be degraded almost completely and the active groups or substituents of norfloxacin (NOR) can be destroyed also, which greatly reduced the biological toxicity of phenol and norfloxacin in water. The possible mechanisms of improving the photocatalytic activity and stability of TiO2 by using Fe-complex are proposed based on free radical capture test and density functional theory calculation. It is clearly that the interfacial interaction between Fe-complex and titanium dioxide directly affects the photocatalytic activity and stability of the composite photocatalyst. The conjugated structure of the complexes plays a crucial role.

    关键词： Photocatalystic degradation under visible light,Phenol,Norfloxacin,Fe-complex/TiO2 composite

    更新于2025-09-09 09:28:46

  • Disubstituted Aminoanthraquinone-Based Photoinitiators for Free Radical Polymerization and Fast 3D Printing under Visible Light

    摘要： The development of highly efficient and rapid photoinitiating systems for free radical photopolymerization under the irradiation of visible light has attracted increasing attention due to their widespread potential applications in, for example, 3D printing or dental polymers. Unfortunately, currently available visible-light-sensitive photoinitiators are not efficient enough for 3D printing applications suffering from low printing speeds. Here we describe a series of photoinitiating systems consisting of disubstituted amino-anthraquinone derivatives (i.e., 1-amino-4-hydroxy-anthraquinone, 1,4-diaminoanthraquinone, and 1,5-diamino-anthraquinone) and various additives (e.g., tertiary amine and phenacyl bromide) toward the free radical photopolymerization of various acrylate monomers (such as commercial 3D resin) under the irradiation of blue to red LEDs. It is shown that the type and position of substituents of the aminoanthraquinone derivative can significantly affect its photoinitiation properties. The most efficient disubstituted aminoanthraquinone derivative-based photoinitiating system was selected and used for the 3D printing of a commercial 3D resin in a 3D printer with polychromatic visible light as the irradiation source. It is shown that its printing speed was dramatically enhanced compared to a commercial photoinitiator 2,4,6-trimethylbenzoyldiphenylphosphine oxide (TPO).

    关键词： aminoanthraquinone derivatives,free radical photopolymerization,photoinitiating systems,visible light,3D printing

    更新于2025-09-09 09:28:46