Magnetic, Electrical, and Microstructural Properties of YBa2Cu3O7: A Comparison of Sol-gel, Co-precipitated, and Solid-state Processing Routes.
NUR AZMINA BINTI SIDEK
A proposal submitted in fulfilment of the requirements for the degree of Bachelor of Applied Science (Material Technology) with Honours
FACULTY OF BIOENGINEERING AND TECHNOLOGY UNIVERSITY MALAYSIA KELANTAN
1.1 Background of study
Superconductivity is a promising technology that helps to prevent the energy from loss. Since discovered in 1911 by Dutch physicist Heike Kamerlingh, superconductor material has been used widely in many fields for example in electrical, medical and electronic.
This followed by discovery of yttrium barium copper oxide (YBa2Cu3O7) in 1987 by Muller and Bednorz. This YBa2CuO7 received a great intention from many researchers.
Many methods have been introduced in order to prepare the YBa2Cu3O7. Each method gives a different properties of samples. Not all the techniques are suitable to be used in preparing the YBa2Cu3O7 superconductor.
1.2 Problem statement
Ceramic superconductor has been used in many fields especially in the application that require to carry high current. Theoretically, YBa2CuO7 is one of the ceramic superconductors that has an excellent ability to carry higher critical current density (JC) and this is the reason, YBa2CuO7 is chosen. Todays, many methods have been introduced in order to synthesis the YBa2CuO7
However, each method have their own advantages and disadvantages. Brittleness and low critical current are a major problem of the ceramic samples.
The objectives of this study are:
To study the magnetic, electrical and microstructural properties of YBA2CuO7To compare the sol-gel method, co-precipitated method and solid-state method that is used to prepare the YBA2CuO7
1.4 Significant of study
The result of this study is to present the properties of YBA2CuO7 using different method. There are many methods that can be used to synthesis the YBa2CuO7 but not all the methods show a good performance in properties of the samples. The sol-gel processing routes produce small distribution of the grain size and show highly pure homogeneity of composition in the YBA2CuO7 samples
Sol-gel process can enhance the properties of superconductor samples of critical current, critical field and Meissner effect.
As the consequences, the electrical, magnetic and microstructural properties of YBa2CuO7 superconductor will increased.
2.0 Literature review
Since the discovery of the high temperature superconductor (HTS), extensive studies have been carried out in order to develop these materials for applications Superconductivity is a phenomenon where the electrical current can conduct electricity with a zero resistance.
2.3 Properties of YBa2Cu3O7 YBa2Cu3O7 is the first superconductor which was discovered in 1987 by Wu et al. There are three different metals in the YBa2Cu3O7 which are yttrium(Y), barium (Ba) and, copper (Cu). It exists in 1:2:3 mole ratio respectively.
2.4 Sol-gel method
2.5 Co-precipitated method
2.6 Solid-state method
2.7.1 X-ray powder diffraction
2.7.2 Scanning electron micrographs
2.7.3 Energy dispersive x-ray spectra
Material and methods
The material that will be used in this study are yttrium nitrates, barium nitrates, and copper nitrates with molecular weight 274.918 g/mol, 261.337 g/mol, and 187.556 g/mol respectively. These materials are used to prepare the YBa2Cu3O7 using solution method. For solid-state samples, the high purity of Y2O3, BaCO3, and CuO will be used. The nitrates of yttrium, barium, and copper will be used to prepare the YBa2Cu3O7. These materials are synthesis into the powder form to get a pellet.
The samples will be prepare using three different techniques which are sol-gel technique, co-precipitated technique, and solid-state technique.
3.2.1 Preparation of samples using sol-gel technique
The nitrates of yttrium, barium and copper will be reflux overnight at 353 K in ethylene glycol to achieve complete solubility. A blue-green precipitate will be appeared when the solution is heated to 403 K. The solution will be heated to 453 K after refluxing to make the ethylene glycol evaporate. The product will shows an oily, brown slurry which will only shows copper metal that can be see in the x-ray powder diffraction pattern. At a rate of 2 K / min the slurry will be heated and annealed at 1223 K for 5 hours.
3.2.2 Preparation of samples using co-precipitated
3.2.3 Preparation of samples using solid-state
Activities Jan Feb Mar Apr May Jun July Aug Sep Oct Nov Dec
Selection of project title Literature review Proposal writing report Proposal presentation Final draft proposal submission Conduct the experiment Analysis of data Final report writing Final presentation Milestones
Milestones End date
Completion of final draft proposal 28/6/2019
Completion of sample preparation 15/7/2019
Completion of experiment 30/9/2019
Completion of report 28/11/2019