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Method for Determining Volumetric Efficiency and Its Experimental Validation

: Kaunas University of Technology, 2016, pp. 589–593. ISSN 2351-7034. [3] A. Ambrozik, Analysis of Working Cycles in Four-Stroke IC Engines . Kielce University of Technology, Kielce, 2010. [4] A. Ambrozik, Selected Problems in Thermal Processes in Piston Internal Combustion Engines. Kielce University of Technology, Kielce, 2003. [5] O. A. Özsoysal, “Effects of Combustion Efficiency on a Dual Cycle,” Energy Conversion and Managemen , vol. 50, no. 9, pp. 2400–2406, 2009. https://doi.org/10.1016/j.enconman.2009.05.029 [6] B. Sahin, O. A. Özsoysal

Open access
Development of sol-gel derived gahnite anti-reflection coating for augmenting the power conversion efficiency of polycrystalline silicon solar cells

Abstract

The present research is focused on developing ZnAl2O4 (gahnite) spinel as an antireflection coating material for enhanced energy conversion of polycrystalline silicon solar cells (PSSC). ZnAl2O4 has been synthesized using dual precursors, namely aluminum nitrate nonahydrate and zinc nitrate hexahydrate in ethanol media. Diethanolamine has been used as a sol stabilizer in sol-gel process for ZnAl2O4 nanosheet fabrication. ZnAl2O4 nanosheet was deposited layer-by-layer (LBL) on PSSC by spin coating method. The effect of ZnAl2O4 coating on the physical, electrical, optical properties and temperature distribution in PSSC was investigated. The synthesized antireflection coating (ARC) material bears gahnite (ZnAl2O4) spinel crystal structure composed of two dimensional (2D) nanosheets. An increase in layer thickness proves the LBL deposition of ARC on the PSSC substrate. The ZnAl2O4 2D nanosheet comprising ARC on the PSSC was tested and it exhibited a maximum of 93 % transmittance, short-circuit photocurrent of 42.364 mA/cm2 and maximum power conversion efficiency (PCE) 23.42 % at a low cell temperature (50.2 °C) for three-layer ARC, while the reference cell exhibited 33.518 mA/cm2, 15.74 % and 59.1 °C, respectively. Based on the results, ZnAl2O4 2D nanosheets have been proven as an appropriate ARC material for increasing the PCE of PSSC.

Open access
Efficiency enhancement of natural dye sensitized solar cell by optimizing electrode fabrication parameters

Abstract

Efficiency of dye-sensitized solar cell (DSSC) depends on several interrelated factors such as type and concentration of dye, type and thickness of photoelectrode and counter electrode. Optimized combination of these factors leads to a more efficient cell. This paper presents the effect of these parameters on cell efficiency. TiO2 nanoporous thin films of different thicknesses (5 μm to 25 μm) were fabricated on indium doped tin oxide (ITO) coated glass by doctor blading method and characterized by inverted microscope, stylus surface profiler and scanning electron microscope (SEM). Natural organic dye of different concentrations, extracted from turmeric, was prepared with ethanol solvent. Different combinations of dye concentrations and film thicknesses along with different types of carbon catalyst have been investigated by I-V characterization. The result shows that the cell made of a counter electrode catalyst material prepared by candle flame carbon combined with about 15 μm thick photoelectrode and 100 mg/mL dye in ethanol solvent, achieves the highest efficiency of 0.45 %, with open circuit voltage of 566 mV and short circuit current density of 1.02 mA/cm2.

Open access
Application Of Sustainable Design Principles To Increase Energy Efficiency Of Existing Buildings

References [1] ABCB (2014), “NCC Volume One Energy Efficiency Provisions”, Australian Building Codes Board, https://scavinutwal.files.wordpress.com/2015/10/abcb-energy-efficiency-handbook.pdf . [2] CRES (2000), “Energy Audit Guide”, Centre for Renewable Energy Sources, Athens. [3] Department of Industry (2013), “Your Home”, 5th edition, Commonwealth of Australia. [4] DEWHA (2008), “Energy Use in Australian Residential Sector”, Department of the Environment, Water, Heritage and the Arts. Energy Rating (2014), Retrieved from http

Open access
A novel photoelectrode of NiO@ZnO nanocomposite prepared by Pechini method coupled with PLD for efficiency enhancement in DSSCs

Abstract

The dye-sensitized solar cells made of NiO@ZnO nanoparticles were synthesized by a novel Pechini route using different NiO molar concentration ratios. The thermal, structural morphological, optical and electrical properties of the prepared samples were investigated using thermal gravimetric analysis and differential scanning calorimetery (TGA/DSC), X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), FT-IR and Raman spectroscopy, UV-diffuse reflectance (UV-DRS), photoluminescence (PL) and current-voltage (I-V) measurements. The success of doping process was confirmed by the XRD patterns, which revealed the existence of new peak at 43.2° corresponding to secondary phase NiO. UV spectra exhibited red shifts in NiO doped ZnO NCs and PL spectra showed strong emission band at 355 nm. The doping of ZnO with NiO was intended to enhance the surface defects of ZnO. The current-voltage measurements showed an improvement of the short circuit photocurrent (Jsc) and fill factor (FF) and a decrease in the open circuit voltage (VOC) for dye-sensitized solar cell (DSSC) based on NiO-ZnO NCs. A clear enhancement in efficiency of DSSC from 1.26±0.10 % for pure ZnO to 3.01±0.25 % for NiO-ZnO NCs at the optimum doping with 1.5 mol% of NiO to ZnO (ZN1.5) was observed. The obtained material can be a suitable candidate for photovoltaic applications.

Open access
Growth, electrical, thermal, mechanical and etching studies on 4-chloroanilinium hydrogen (2R, 3R)-tartrate monohydrate-an organic NLO single crystal

Abstract

An organic single crystal of 4-chloroanilinium hydrogen (2R,3R)-tartrate monohydrate (4CAHT) was grown by slow evaporation solution growth technique at room temperature. Single crystal XRD study confirmed that the crystal belongs to monoclinic system with the space group P21. Powder XRD analysis confirmed the crystalline nature of the compound. The presence of various functional groups in the compound was revealed by FT-IR analysis. UV studies showed the absence of absorption in the entire visible region. To determine the thermal stability of the grown crystals it was subjected to thermogravimetric and differential thermal analyses. Microhardness and etching studies were also carried out for the crystal. The powder second harmonic generation efficiency of 4CAHT was tested by Kurtz and Perry powder technique and the relative SHG efficiency of 4CAHT was found to be 1.44 times greater than that of standard KDP.

Open access
Studies on the growth and characterization of L-cysteine hydrogen fluoride single crystal

Abstract

L-cysteine hydrogen fluoride (LCHF) single crystals were grown from aqueous solution. Single crystal X-ray diffraction, FT-IR, UV-Vis-NIR, and TG-DTA were used to test the grown crystals. The specimen dielectric and mechanical behaviors were also studied. Powder X-ray diffraction of the grown crystal was recorded and indexed. The optical properties of the LCHF crystal were determined using UV-Vis spectroscopy. It was found that the optical band gap of LCHF was 4.8 eV. The crystal functional groups were identified using FT-IR. Second harmonic generation (SHG) efficiency of the LCHF was three times higher than that of KDP. The dielectric constant, dielectric loss and AC conductivity were measured at different frequencies and temperatures.

Open access
Growth, characterization and optical properties of potassium iodide (KI) doped potassium hydrogen phthalate (KHP) single crystals for optoelectronic applications

Abstract

Potassium iodide (KI) doped potassium hydrogen phthalate (KHP) single crystals were grown by slow evaporation technique using millipore water as a solvent. The grown single crystals were analyzed by powder X-ray diffraction and the analysis confirmed that KI-doped KHP crystallizes in orthorhombic system with space group Pca21. The functional groups were identified by FT-IR technique which showed slight shift in vibrational frequencies, indicating inclusion of dopant into the crystal lattice. The UV-Vis spectral studies revealed the optical transparency of the doped crystals in the entire visible region. The optical band gap values were estimated from Tauc plots. Kurtz-Perry powder test was employed for second harmonic generation efficiency studies of the grown crystals.

Open access
Synthesis, growth and characterization of semiorganic nonlinear optical single crystal bis(thiourea) barium nitrate (BTBN) for frequency conversion

Abstract

A novel semiorganic nonlinear optical (NLO) crystal, bis(thiourea) barium nitrate (BTBN) was synthesized and grown by slow evaporation method. Structure of the new crystalline compound was confirmed by single crystal X-ray diffraction analysis and it showed that BTBN belongs to orthorhombic crystal system. The crystalline nature of the BTBN was confirmed by powder X-ray diffraction study. Important functional groups of BTBN were identified by FT-IR spectroscopic analysis. UV-Vis-NIR spectral study showed that the grown crystal is transparent in the entire visible region with low cut off wavelength of 304 nm. BTBN exhibits a SHG efficiency which is nearly 2.38 times higher than that of KDP. The BTBN crystal has high mechanical strength and belongs to soft category, which was confirmed by micorhardness study. The thermal stability of BTBN was determined from TGA and DTA thermal study which revealed that the BTBN crystal has thermal stability up to 243.1 °C. The surface properties and presence of elements was analyzed by SEM and EDAX study, respectively.

Open access
Investigation on nonlinear optical and dielectric properties of L-arginine doped ZTC crystal to explore photonic device applications

device applications. As doping can largely influence the characteristic traits of the crystal system, various researchers have re-investigated the ZTC crystal using different amino acids. The positive impact of glycine on structural, UV-Vis, thermal and SHG efficiency of ZTC crystal has been reported in the literature [ 3 ]. The improved structural, linear-nonlinear optical and thermal studies of L-alanine doped ZTC crystal have been explored [ 4 ]. The influence of L-cysteine on optical transparency, SHG efficiency, photoluminescence, thermal and dielectric properties

Open access