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Effect of Cu2O Morphology on Photovoltaic Performance of P-Type Dye-Sensitized Solar Cells

Abstract

Cuprous oxide with different morphologies (3D hierarchical structure consisting of the micrometer dendritic rods and the porous truncated octahedrons) has been successfully synthesized via a facile one-step hydrothermal method using copper (II) acetate and ethyl cellulose as reactants. The p-type dye-sensitized solar cell based on the micrometer porous structure exhibits approximately 15% increase in JSC and VOC than 3D hierarchical structure. This enhancement could be explained by the high dye loading capacity of this porous structure and lowering the recombination process at the oxide/dye/electrolyte interface.

Open access
Fluid Flow Control in Domestic Hot Water Systems During Days with Different Radiative Stability Levels

storage tanks Energy Conversion and Management 49 ( 2008) 169–184 [5] V. Badescu, S. Budea, M. Paulescu. Empirical versus optimal control of flow in solar domestic hot water systems. J Energ Eng. 2015, 142 (3) (2015), 15-38 [6] S. Budea, V. Bădescu. Improving the Performance of Systems with Solar Water Collectors Used in Domestic Hot Water Production, Energy Procedia, 112 (2017), 398-403 [7] J. A. Duffie, W.A. Beckman Solar energy thermal processes (New York: Wiley) (1991) [8] I. G. Carabogdan et al. Industrial thermal installations

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Comparison Between Measurements and WRF Numerical Simulation of Global Solar Irradiation in Romania

Abstract

The paper presents a comparative analysis between the surface global irradiation measured for Romania and the predicted irradiation obtained by numerical simulation. The measured data came from the Romanian National meteorological Administration. Based on a preliminary analysis that took into account several criteria among which, performance, cost, popularity and meteorological and satellite data accessibility we concluded that a combination GFS-WRF(NMM) or GFS-WRF(ARW) is most suitable for short term global solar irradiation forecasting in order to assess the performance of the photovoltaic power stations (Badescu and Dumitrescu, 2012, [1], Martin et al., 2011, [2]).

Open access
The Aharonov-Bohm Effect and Transport Properties in Graphene Nanostructures

Abstract

This paper investigates the possibility to improve the filtering process of flue gas by separation of suspended nanoparticle using dielectrophoresis. The study focuses on the particles having an average radius of about 50-150 nm, that cannot be filtrated by classical techniques but have a harmful effect for environment and human health. The size distribution nanoparticles collected from the flue gas filters of a hazardous waste incinerator plant were evaluated. Based on obtained experimental data and a proposed mathematical model, the concentration distribution of nanoparticle suspended in flue gas inside a microfluidic separation device was analyzed by numerical simulations, using the finite element method. The performances of the device were described in terms of three new specific quantities related to the separation process, namely Recovery, Purity and Separation Efficiency. The simulations could provide the optimal values of control parameters for separation process, and aim to be a useful tool in designing microfluidic devices for separating nanoparticle from combustion gases.

Open access
Effectiveness of GEANT4 in Monte Carlo Simulation Studyofphonon Conduction in Sn Host with Si Nanowire Interface

Abstract

We have explored the effectiveness of Geant4 by using it to simulate phonon conduction in Sn Host with Si Nanowire Interface. Our Monte Carlo Simulation shows that the effectiveness of the phonon conduction Geant4 simulation increases when the system attained a steady state of 100 time steps. We have simulated phonon conduction in Sn host with Si nanowire interface using a Geant4Condensed Matter Physics Monte Carlo simulation toolkit in a low cost and less powerful processing computer machine. In the simulation, phonons were displaced inside a computation domain from their initial positions with the velocities and direction vectors assigned to them. A time step was selected so that a phonon can move at most the length of one sub-cell in one time step. Our phonon conduction analysis of SiSn based alloy using Geant4 showed performance enhancement and reasonable predicted thermal values. Numerical predictions of the thermal profile simulations of the values of the temperature in each cell were all within ten percent of the average temperature of Silicon – Tin.

Open access
The Influence of the Precursor Type and of the Substrate on the SPD Deposited TiO2 Photocatalytic Thin Films

Abstract

Photocatalytic degradation of organic pollutants from wastewater using titanium dioxide is recognized as an efficient process. To be feasible, this process needs to be solar- or visible light -activated, but, due to its wide band gap energy, titanium dioxide can only be activated by ultraviolet radiation. In this paper, thin films of titanium dioxide were deposited by Spray Pyrolysis Deposition using organo-metallic (titanium-iso-propoxide) and inorganic (titanium chloride) precursors, as a first step in optimizing the deposition process of titanium dioxide - carbon composite thin films, active in the visible spectral range. The thin films were characterized to outline the differences when using these two precursor solutions, when deposited on Fluorine doped Tin Oxide-glass, regular glass and microscopic glass, in terms of crystallinity (by using X-ray diffraction), elemental composition (using Energy Dispersive X-ray spectrometry), surface morphology (Scanning Electronic Microscopy and Atomic Force Microscopy). The photocatalytic activity of the titanium dioxide thin films was investigated based on the removal efficiencies of methylene blue from a synthetically prepared wastewater. The samples deposited using the inorganic precursor show higher roughness, and this proves to be the most important factor that influences the phocatalytic processes. After 8 hours of ultraviolet irradiation, methylene blue removal efficiencies up to 36% were observed; the highest removal efficiency was registered using the thin titanium dioxide film obtained using the titanium chloride precursor, deposited on fluorine doped tin oxide glass substrate, due to the titanium dioxide-tin dioxide semiconductor tandem formed at the interface, that limits the electron-hole recombination, thus increasing the photoctalytic performance of the substrate.

Open access
Improved Model for Forecasting Global Solar Irradiance During Sunny and Cloudy Days

References [1] ***, The Directive 2010/31/EU of the European Parliament and of the Council of 19 May 2010 on the energy performance of buildings , Official Journal of the European Union, 53 (2010). [2] Aelenei L., Gonçalves H., From solar building design to Net Zero Energy buildings: Performance insights of an office building , Energy Procedia, 48 (2014), 1236–1243. [3] Burduhos B.G., Neagoe M., Duta A., Adaptive Stepwise Orientation Algorithm for Non-concentrated Dual-Axis Solar Tracking Systems , Proc. of 14th World Congress in Mechanism

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Optical Modeling and Simulation of Tandem Metal Oxide Solar Cells

simulation of cuprous oxide heterojunction solar cells, Jpn. J. Appl. Phys. 54 (2015) 112303 [4] R. Mitroi, V. Ninulescu, L. Fara. Tandem solar cells based on Cu 2 O and c-Si subcells in parallel configuration: numerical simulation, International Journal of Photoenergy 2017 (2017) 7284367 [5] R. Mitroi, V. Ninulescu, L. Fara. Performance optimization of solar cells based on heterojunctions with Cu 2 O: numerical analysis. Journal of Energy Engineering 143(4) (2017) 04017005 [6] L. Fara, M. Yamaguchi. Advanced Solar Cell Materials, Technology, Modeling

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Impact of Aerosol on the Estimation Accuracy of Solar Radiation

-82 [5] D. Calinoiu, N. Stefu, R. Bota, R. Blaga, N. Pop, E. Paulescu, A. Sabadus, M. Paulescu. Energy Conversion and Management 164(2018) 175-187 [6] C. Gueymard. SMARTS2, A Simple Model of the Atmospheric Radiative Transfer of Sunshine: Algorithms and performance assessment, FSEC-PF-270-95 (1995) [7] W. Spencer. Search 2(1971) 172. [8] Aerosol Robotic Network. https://aeronet.gsfc.nasa.gov/ (Accessed July 2018) [9] Baseline Surface Radiation Network http://bsrn.awi.de/ (Accessed July 2018) [10] Measurements and Instrumentations Data

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