טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentGreenberg Ya'akov
SubjectYBCO Nanofibers Synthesized By Electrospinning a Solution of
Poly(acrylic acid) and Metal Nitrates
DepartmentDepartment of Mechanical Engineering
Supervisor Professor Eyal Zussman
Full Thesis textFull thesis text - English Version


Abstract

One of the most actively studied high temperature superconductor ceramics (HTSC) materials is YBCO (YB2Cu3O7-δ). In this research project a versatile approach to the synthesis of YBCO nanofibers was developed. YBCO nanofibers were synthesized by pyrolysis of nanofibers generated by electrospinning a polymer precursor solution containing poly(acrylic acid) and a mixture of metal nitrates. Typical YBCO nanofibers were 50-100 nm in diameter and around of 10 m length. The nanofibers also contain relatively small amounts of yttrium oxide and copper yttrium oxide.


Microstructure of these nanofibers was studied with the aid of various characterization techniques (TEM, TGA, X-ray, EDS, and EELS) and compared with the microstructure reported in the literature.

The main findings of this research are:


1. The nanofibers contained YB2Cu3O6.8 as main phase, with polycrystalline

 microstructure.

2. By incorporation of calcium into the polymer solution from which the

nanofibers is produced a Single crystal nanofiber is created.

3. Controlling the nanofiber formation can be optimized by controlling the

 decomposition stages through a correct temperature regime.