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Thin-Film FTO-ZnO-CZTS Solar Cells Fully Deposited by Spray Pyrolysis
Salif Cisse,
Maria Covei,
Jean Jude Domingo,
Anca Duta
Issue:
Volume 4, Issue 1, June 2019
Pages:
1-8
Received:
26 May 2019
Accepted:
18 June 2019
Published:
27 June 2019
Abstract: Thin films of ZnO, CZTS (Cu2ZnSnS4) and ZnO-CZTS were prepared by spray pyrolysis deposition (SPD). After spraying a precursor solution of ZnO directly onto fluorine-doped tin oxide (FTO) substrats, CZTS thin layers were sprayed onto layers of ZnO to forme a p-n junction. Some CZTS layers were directly spray onto fluorine-doped tin oxide substrats. ZnO is a wide band gap n-type material, consisting of abundant and nontoxic elements, and is thus expected to be a good substitute for CdS buffer layer in solar cells. In this paper, we report the study of CZTS and ZnO thin films synthesized by chemical spray pyrolysis (CSP) method. During the deposition of the ZnO thin films on the FTO substrats the number of sequences was varied from 20 to 40. The influence of the ZnO on the structural, optical, morphological and electrical properties of CZTS films was studied using various techniques. The X-ray diffraction studies showed the formation of kesterite (Cu2ZnSnS4) phases with the peaks corresponding to (112), (220) and (312) planes. SEM study revealed a lack of uniformity of the surface of the CZTS layers sprayed onto the ZnO layers for a lower thickness of ZnO (FTO-ZnO20-CZTS). The band gap values of FTO-CZTS and FTO-ZnO-CZTS thin films were measured and found in the range 2.2 - 2.25 eV which are in good agreement with the results reported (2-2.2 eV). The morphological studies revealed the formation of some clusters randomly distributed on the film surface in the ZnO-containing layers, i.e. the FTO-ZnO20-CZTS and Finally, current-voltage measurements for different PV cells with maximum efficiency were carried out. A conversion efficiency (η) of 5.99% with fill factor (FF) = 18.8%, open circuit voltage (Voc) = 0.54 V, short circuit current density (Jsc) = 59 mA.cm2 were recorded through the FTO-ZnO40-CZTS thin film PV cell.
Abstract: Thin films of ZnO, CZTS (Cu2ZnSnS4) and ZnO-CZTS were prepared by spray pyrolysis deposition (SPD). After spraying a precursor solution of ZnO directly onto fluorine-doped tin oxide (FTO) substrats, CZTS thin layers were sprayed onto layers of ZnO to forme a p-n junction. Some CZTS layers were directly spray onto fluorine-doped tin oxide substrats....
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A Review of Two-Dimensional Materials in Electrocatalysis and Their Potential Applications
Yau Jamilu Muhammad,
Mikail Abdulkarim Alhaji,
Mohammed Abdullahi Gele,
Badamasi Haruna,
Sirajo Alhassan,
Dauda Garba,
Ahmed Misbahu
Issue:
Volume 4, Issue 1, June 2019
Pages:
9-22
Received:
30 May 2019
Accepted:
19 June 2019
Published:
29 June 2019
Abstract: Two-dimensional materials are crystalline materials consist of a single layer of atoms and sometimes referred to as single layer materials. Electrocatalytic energy conversion using renewable power sources is one of the most promising ways for energy storage and energy utilization in the new century. Over the past years, a great number of two-dimensional (2D) materials have been explored for various electrocatalytic reactions, such as the hydrogen evolution reaction, Carbon (IV) oxide (CO2) reduction reaction and Oxygen (O2) reduction reaction. This research provides an overview on the synthesis techniques of materials including bottom up approaches such as chemical vapor deposition (CVD) and physical vapor deposition (PVD) and top-down approaches like mechanical exfoliation, chemical exfoliation. Then, the characterization techniques of the two-dimensional (2D) materials such as Raman spectroscopy, X-ray diffraction, temperature-dependent resistivity and magnetic susceptibility and scanning tunneling microscopy (STM) are reviewed. Finally, potential applications of two-dimensional (2D) materials and conclusion, challenges and future work are discussed.
Abstract: Two-dimensional materials are crystalline materials consist of a single layer of atoms and sometimes referred to as single layer materials. Electrocatalytic energy conversion using renewable power sources is one of the most promising ways for energy storage and energy utilization in the new century. Over the past years, a great number of two-dimens...
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Fabrication of AA6061-T6/Al2O3 Reinforced Nanocomposite Using Friction Stir Welding
Tanvir Singh,
Shalabh Kumar Tiwari,
Dinesh Kumar Shukla
Issue:
Volume 4, Issue 1, June 2019
Pages:
23-31
Received:
24 May 2019
Accepted:
25 June 2019
Published:
9 July 2019
Abstract: In the present work, attempts were made to join AA6061-T6 sheets by Friction Stir Welding (FSW) process. Al2O3 nanoparticles were added into the aluminum matrix for refining the microstructure of the nugget zone (NZ) and to restrict the growth of granularly in the heat-affected zone (HAZ). In order to illustrate the influence of Al2O3 nanoparticles on mechanical properties, namely ultimate tensile strength, micro-hardness distribution, and wear resistance of the welded joints, FSW was conducted with and without nanoparticles at a constant rotating velocity of 2000 rpm and transverse velocity of 70 mm/min. For characterization of microstructures, optical and scanning electron microscopes were employed. The findings revealed that Al2O3 nanoparticles addition along the joint line resulted in remarkable refining of grains structure in the weld nugget zone. This was due to the pinning effect produced by nano-sized Al2O3 particles which prevent the grain growth followed by recrystallization during FSW, leading to a remarkable reduction in grain size. Also, the sample with nanoparticles joined at rotating and transverse velocities of 2000 rpm and 70 mm/min showed higher tensile properties than the sample without nanoparticles. However, the employment of single FSW pass resulted in an unusual Al2O3 nanoparticles distribution and void initiation at the interface between Al-matrix and Al2O3 nanoparticles in the heat-affected zone resulted in the early fracture of welded joints during tensile loading. Moreover, Al2O3 nanoparticles addition results in the reduction of frictional coefficient and increment in wear resistance due to fine small grains size and large distribution of hardness in NZ of friction stir welded specimens.
Abstract: In the present work, attempts were made to join AA6061-T6 sheets by Friction Stir Welding (FSW) process. Al2O3 nanoparticles were added into the aluminum matrix for refining the microstructure of the nugget zone (NZ) and to restrict the growth of granularly in the heat-affected zone (HAZ). In order to illustrate the influence of Al2O3 nanoparticles...
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Manufacturing, Physical and Chemical Characterization of Fire Clay Brick Value Added with Cow Dung Ash
Pius Rodney Fernando,
Somasundaram Krishanth,
Nilantha Bandara Rathnayake,
Shanilka Aruni Welarahne
Issue:
Volume 4, Issue 1, June 2019
Pages:
32-36
Received:
25 May 2019
Accepted:
24 June 2019
Published:
12 July 2019
Abstract: Aim of this study was to introduce an eco-friendly, low cost and durable clay bricks with partial substitution of Cow Dung Ash (CDA). Five types of clay brick, consist CDA percentages 0, 5 10, 15 and 20% to the total weight of mixture, were manufactured by employing traditional method of dimension (18.5×8.5×6.5) cm3. The clay and CDA were well mixed with the addition of sufficient amount of water to form a good workability. Green molded bricks were allowed to dry under sunlight for two days and then fired in the traditional brick kiln. Physical properties of the burned red bricks were then tested and analyzed with Sri Lankan and British Standard Specifications. The average density, water absorption, compressive strength and flexural strength for 10% Cow Dung Ash (CDA) are 1447 kg.m-3, 17%, 150 kg.cm-2 and 0.82 kg.cm-2 respectively. These physical properties were compared with the standard brick purely manufactured from clay. From the results, clay-CDA bricks are obviously superior to the control brick; those are available in the Eastern region markets.
Abstract: Aim of this study was to introduce an eco-friendly, low cost and durable clay bricks with partial substitution of Cow Dung Ash (CDA). Five types of clay brick, consist CDA percentages 0, 5 10, 15 and 20% to the total weight of mixture, were manufactured by employing traditional method of dimension (18.5×8.5×6.5) cm3. The clay and CDA were well mixe...
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Determination of Work Index for Iperindo Lode Gold Deposit at Ilesha Goldfield Osun State, Nigeria Using Modified Bond Index
Adetula Yomi Vincent,
Ozah Blessing,
Alabi Oladuni Oyelola,
John Ade Ajayi,
Akoja Ayo
Issue:
Volume 4, Issue 1, June 2019
Pages:
37-42
Received:
3 June 2019
Accepted:
3 July 2019
Published:
13 July 2019
Abstract: Iperindo lode gold is one of the few primary gold deposits known in Nigeria. The mineralized lodes generally comprise highly silicified fine-grained foliated biotite gneiss typically intruded by both discordant and concordant pegmatitic quartz-feldspar veins. The research investigates the work index of Iperindo lode deposit at Ilesha goldfield in Osun state, Nigeria. The sample of the gold ore was sourced from Iperindo at Ilesha Local Government Area of Osun state, Nigeria. The reference ores (quartz) sample was also sourced from that serves as overburden to the goldmine. The test ore and the reference ore were characterized using Energy Dispersed X-ray fluorescence spectrometer. 500 grams of gold ore and quartz were sampled and prepared by crushing and grinding to 100% passing 710µm sieve; 100 grams of prepared ores were charged into array of sieve arranged in √2 i.e from 500 μm to -45 μm. Set of sieves were mounted on automated sieve shaker and was operated for 20 minutes. The work index of reference ore was used to calculate the work index of the test ore using Gaudin Schuman expression to obtain a work index of 11.92kwh/ton for test ore. This work index value obtained for Iperindo gold ore (test ore) lies favorably within the work index of 8 – 16.5kwh/ton for gold ore sighted in the literature.
Abstract: Iperindo lode gold is one of the few primary gold deposits known in Nigeria. The mineralized lodes generally comprise highly silicified fine-grained foliated biotite gneiss typically intruded by both discordant and concordant pegmatitic quartz-feldspar veins. The research investigates the work index of Iperindo lode deposit at Ilesha goldfield in O...
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Synthesis, Spectral and Thermal Characterization of Cu(II) Complexes Containing Schiff Base Ligands and Their Antibacterial Activity Study
Kismat Ara Elachi,
Saddam Hossain,
M. M. Haque,
Ranjan K. Mohapatra,
Kudrat-E-Zahan
Issue:
Volume 4, Issue 1, June 2019
Pages:
43-53
Received:
27 May 2019
Accepted:
25 June 2019
Published:
15 July 2019
Abstract: Four complexes of Cu(II) ions containing Schiff base ligands, L1 (C20H14O4N4) [N,N`-Bis-(2-nitro-benzylidene)-benzene-1,2-diamine] derived from condensation reaction of o-phenylenediamine and 2-nitrobenzaldehyde, L2(C8H8N3SCl)[2-(2-chlorobenzylidene) hydrazinecarbothioamide] derived from condensation reaction of thiosemicarbazide and o-chlorobenzaldehyde and L3(C9H11N3OS) [2-(4-methoxybenzylidene)-hydrazinecarbothioamide, derived from the condensation reaction of anisaldehyde and thiosemicarbazide respectively. The synthesized ligands and their metal complexes were isolated in solid state from the reaction medium and characterized by molar conductivity measurement, magnetic susceptibility, infrared, electronic spectral, thermal analysis and some physical measurements. The overall reactions were monitored by TLC analysis.
Abstract: Four complexes of Cu(II) ions containing Schiff base ligands, L1 (C20H14O4N4) [N,N`-Bis-(2-nitro-benzylidene)-benzene-1,2-diamine] derived from condensation reaction of o-phenylenediamine and 2-nitrobenzaldehyde, L2(C8H8N3SCl)[2-(2-chlorobenzylidene) hydrazinecarbothioamide] derived from condensation reaction of thiosemicarbazide and o-chlorobenzal...
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Development of a Simplistic Method to Simulate the Formation of Intermetallic Compounds in Diffusion Soldering Process
Chironjeet Chaki,
Manoshi Chaki,
Keya Roy
Issue:
Volume 4, Issue 1, June 2019
Pages:
54-61
Received:
30 May 2019
Accepted:
2 July 2019
Published:
15 July 2019
Abstract: A simplistic simulation technique has been developed for computing the individual intermetallic compound (IMC) thickness which is formed in substrate-solder (Cu-Sn) systems during the diffusion soldering process in high-temperature power electronic applications. The method requires the time-dependent temperature profile for the soldering process and the growth rate parameters (e.g. concentration gradient, diffusion coefficient, activation energy, etc.) for the development of IMC layers as input. The method is suitable for predicting the thickness of an intermetallic phase layer during the diffusion soldering process. As such, it can be used in high-temperature power electronic application’s solder processing to enhance the reliability and lifetime of solder interconnections by allowing the control of the thickness of IMC layers. The method is demonstrated for IMC growth between pure copper as substrate and pure Sn as solder material. The growth behavior of the IMC layer is increased with increasing temperature over time according to the Arrhenius theory in the temperature range between 24°C to 260°C. To simulate the formation of IMC thickness in diffusion soldering interconnections, a simplistic way has been attempted using the popular commercial finite element simulation tool Comsol Multiphysics and scientific computing application ‘Matlab’. By means of transient thermal input, the diffusion-controlled intermetallic phase formation is simulated here. Few assumptions are taken care of this simulation process, for example, no convection, no reaction, solid-solid diffusion, no the pressure effect on the computational domain.
Abstract: A simplistic simulation technique has been developed for computing the individual intermetallic compound (IMC) thickness which is formed in substrate-solder (Cu-Sn) systems during the diffusion soldering process in high-temperature power electronic applications. The method requires the time-dependent temperature profile for the soldering process an...
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