Journal of Photonic Materials and Technology最新文献

{"title":"Influence of Graphene on Sheet Resistivity and Urbach Enery of Nano TiO₂ for DSSC Electrode","authors":"G. Riungu, Simon Mugo, James Ngaruyia, Leonard Gitu","doi":"10.11648/j.jmpt.20241001.12","DOIUrl":"https://doi.org/10.11648/j.jmpt.20241001.12","url":null,"abstract":"Importance of renewable energy cannot be over emphasized. Titanium IV oxide (TiO₂) is the most suitable semiconductor for dye sensitized solar cell (DSSC) due to its chemical stability, non toxicity and excellent optoelectronic properties. In this research TiO₂ is coated on graphene to enhance its charge transport aiming to reduce recombination which is a main set back in DSSCs. undestanding graphene- TiO₂contact is therefore essential for DSSC application. TiO₂ thin films were deposited on single layer graphene (SLG) as well as on flourine tin oxide (FTO) using doctor blading technique. The films were annealed at rates of 2°C /min and 1°C/min up to a temperature of 450°C followed by sintering at this temperature for 30 minutes. Four point probe SRM-232 was used to measure sheet resistance of the samples. The film thickness were obtained from transmittance using pointwise unconstrained minimization approximation (PUMA). UV –VIS spectrophotometer was employed to measure transmittance. Resistivity of TiO₂ on both FTO and Graphene were of order 10^-4 Ωcm. However, TiO₂ annealed on graphene matrix exhibited a slightly lower resistivity 5.6 x10^-4 Ωcm as compared to 6.0x10^-4Ωcm on FTO. Optical transmittance on visible region was lower for TiO₂ on FTO than on SLG, 71.48% and 80.11% respectively. Urbach energy (Eu) for weak absorption region decreased with annealing rate. Urbach energies for 1°C/min TiO₂on FTO and SLG were 361 meV and 261meV respectively. This was used to account for decrease of disoders of films due to annealing. A striking relation between sheet resistivity and urbach was reported suggesting SLG as a suitable candidate for photoanode of a DSSC.\u0000","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"70 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141810546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical Design Impact on PERC Solar Cell Efficiency: Upright Pyramids vs Inverted Pyramids Textured Surfaces","authors":"Papa Touty Traore, Omar Diallo Sadio, M. Ndiaye, I. Diagne","doi":"10.11648/j.jmpt.20230901.11","DOIUrl":"https://doi.org/10.11648/j.jmpt.20230901.11","url":null,"abstract":"","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127414650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Characterization of a Polystyrene (Cork) Doped by Aluminium Oxide (Al2O3) to Improve Its Optical Properties Using the (UV-VIS) Techniques","authors":"Tamador Almardi Albashier, M. H. M. Hilo, A. Suliman","doi":"10.11648/J.JMPT.20200602.11","DOIUrl":"https://doi.org/10.11648/J.JMPT.20200602.11","url":null,"abstract":"Cork is considered one of the polymers of very low industrial value and is used only for secondary purposes such as packaging, and it is possible to have any other uses of high value by doping the cork with materials that can change its physical properties, this paper aimed to synthesize and characterize the optical properties of pure Polystyrene (200 grams) Cork, and Polystyrene (200 grams) Cork doped by Aluminum oxide in ratios (0.1 to 0.9) molar, for the preparation of Aluminum oxide, aluminum nitrate (Al(NO3)39H2O)) was used (as a source of Aluminum oxide, provided by (LOBA CHEMIE) company, with a molecular weight of 375.13 and a concentration of 98%, which is a white powder that is soluble in water, it was prepared at a temperature of (80) degrees Celsius for each Samples with different concentrations ranging from (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9) morality by adding N, N-Dimethylformamide for HPLC and Spectroscopy as an oxidizing agent and precipitant, then by Sol-Gel method at a temperature of 80°C for 60 minutes, samples of doped cork were deposited on glass slides. By using the ultraviolet technique (UV-VIS), the transmittance and absorption spectra were recorded within the wavelength range of (200-800) nm. The results showed that the transmittance decreased with increasing the cork doping percentage. The basic absorption peaks of the cork tends towards the low photon energy (red shift) when increasing the doping rates of Aluminum oxide, while it was tending towards the high energy (blue shift) photon at the cork before doping, and that is through the absorption coefficient values that were calculated from the absorbance spectrum, which is greater than Likewise, the optical parameters of reflectivity, extinction coefficient, and refractive index were calculated. The energy gap of the cork doped by Aluminum oxide is small compared to the energy gap of the pure polystyrene cork. It has been concluded that the Aluminum oxide ratios with different molar values confirm the cause of the energy gap shifts.","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132430083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Light Dispersion in Diamond-like Crystals","authors":"V. Rumyantsev","doi":"10.11648/J.JMPT.20190501.14","DOIUrl":"https://doi.org/10.11648/J.JMPT.20190501.14","url":null,"abstract":"Dispersion of light in diamond-like crystals is investigated. Dispersion laws of exciton polaritons in this structures, which (apart from the diamond itself) include silicon and germanium is obtained within the quasi-molecular model of valent crystals. Dispersion curves point to the fact that in the vicinity of exciton resonance under small damping one must account for the exciton-photon interaction. The calculation shows that in a certain frequency range the existence of an additional light wave is possible. The dispersion laws of exciton polaritons in a diamond-like structure in the vicinity of frequency of the lowest dipole transition of a crystalline quasi-molecule (a σ-bond) are obtained.","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133483339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laser-Induced Fluorescence of Wet Porous Silicon as Laser-Induced Fluorescence of H3O+","authors":"Y. Pivovarenko","doi":"10.11648/J.JMPT.20190501.13","DOIUrl":"https://doi.org/10.11648/J.JMPT.20190501.13","url":null,"abstract":"Typically, the production of porous silicon is an electrochemical etching of monocrystalline silicon wafers, which are connected to the anode, in ethanol-aqueous HF solutions. In the process of etching, it turns out porous silicon, which is saturated with water, which is rich in protonated molecules H 3 O + , formed as a result of a number of well-known physicochemical processes. At the same time, the presence of molecules of such protonated water in the composition of freshly prepared porous silicon is usually ignored. At the same time, both the ability of protonated water to fluoresce under the action of laser radiation in the UV range, and the possible contribution of such fluorescence to the total fluorescence of porous silicon induced by a UV laser is ignored. Since such ignoring seems to be incorrect, the possible contribution of laser fluorescence of water enriched with its protonated molecules to the laser fluorescence of moistened porous silicon is discussed here. Since this may be important for the correct interpretation of the results obtained when studying the spectra of laser-induced fluorescence of porous silicon moistened with aqueous solutions, in particular – with aqueous solutions of biological substances, the unique properties of such water are also demonstrated. Thus, the exceptional penetrating ability of positively charged water is visualized, due to which it is able to transfer from the hydrated shells of biopolymers to porous silicon and enhance its laser-induced fluorescence. It also demonstrates the exceptional ability of positively charged water to evaporate; which makes it possible to explain the rapid disappearance of the fluorescence of porous silicon, which is observed during its drying.","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130492425","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Surface Characterisation of Spin Coated Quaternary Chalcogenide CZT(S, O) Thin Film for Optoelectronic Applications","authors":"R. A. Busari, B. Taleatu, S. Adewinbi, O. E. Adewumi, A. Fasasi","doi":"10.11648/J.JMPT.20190502.13","DOIUrl":"https://doi.org/10.11648/J.JMPT.20190502.13","url":null,"abstract":"Thin films of copper zinc tin sulphide (CZTS) have been deposited on glass substrate at various solution concentration and angular speed using sol-gel spin coating technique. Surface morphology showed that the deposited layers are continuous and pinhole free. The film’s particles are evenly distributed and adhered firmly to the substrates. X-ray diffraction studies revealed that the films are polycrystalline with tetragonal kesterite structure. Interplanar spacing and average crystallite size were estimated as 3.732 A and 56.53 nm. Film’s thickness and stoichiometry were determined from Rutherford Backscattering Spectroscopy (RBS) as127 nm and Cu1.5Zn1.0Sn1.1S4.4O3.3. Optical studies showed that the deposited films exhibit direct band transition. The values of the energy gap were found between 1.30 and 1.60 eV. The result of the study suggested that the deposited CZTS thin films can perform as a good absorber material in nanostructured optoelectronic devices.","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"72 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127264497","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study of the Optical Properties of Isonitrosoacetophenone (C8H7NO2) Using UV-Vis Spectroscopy","authors":"Salma Fath Alrahman Ahmed, K. M. Haroun, A. M. A. Bakheet, Yousif H. Alsheikh, A. Suliman","doi":"10.11648/J.JMPT.20190502.12","DOIUrl":"https://doi.org/10.11648/J.JMPT.20190502.12","url":null,"abstract":"In this work, the optical properties (absorption, absorption coefficient, refractive index, band- gap energy, extension coefficient, and reflection) of the five samples of isonitrosoacetophenone (C8H7NO2) was studied using Uv-Vis spectroscopy. The C8H7NO2 was dissolved in different amounts of (0.5, 1, 1.5, and 2) ml of distilled water. The effect of concentration on the optical properties of C8H7NO2 was investigated experimentally and it was shown that the different values of the calculated optical properties are clearly affected by the concentrations of the C8H7NO2 compound. In addition, when the isonitrosoacetophenone is mixed with 2.0 ml of water the absorbance rate of the pure isonitrosoacetophenone was shown to be decreased from 2.7×10-4 (a. u.) at 278 nm to 1×10-4 (a. u.) at the same wavelength. Furthermore, the transmission of C8H7NO2 was shifted towards the shorter wavelength as the concentration of water is increased, which is starts from ~346 nm for pure isonitrosoacetophenone and decreased to ~ 300 nm when mixed with 2.0 ml of water. The important finding of this work was that the compound C8H7NO2 is opaque (non-transmittance) material from the wavelength of 220 to 300 nm which corresponds to the UV portion of the electromagnetic spectrum and this suggests more study in this area.","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134083309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of Post Annealing Rates on Porosity, Dispersion Energy and Associated Dielectric Energy Losses of TiO₂ Thin Films","authors":"Nelson Mugambi, James Mbiyu Ngaruiya, Simon Waweru Mugo, Geoffrey Gitonga Riungu, Gitonga Mbae John","doi":"10.11648/j.jmpt.20210701.11","DOIUrl":"https://doi.org/10.11648/j.jmpt.20210701.11","url":null,"abstract":"","PeriodicalId":134756,"journal":{"name":"Journal of Photonic Materials and Technology","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123635926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}