טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentAlfassi Juliana
SubjectDeveloping Nanoscale Metastable Intermolecular Composites
(MIC) using SOL-GEL Techniques
DepartmentDepartment of Chemical Engineering
Supervisor Ms. Rina Tannenbaum
Full Thesis textFull thesis text - English Version


Abstract

This study presents synthesis and characterization of MICs of ferric oxide and aluminum synthesized incorporating sol-gel chemistry. Two precursors, ferric nitrate nanohydrate and ferric chloride hexahydrate were used in xerogel synthesis. The xerogels were characterized with combination of HRSEM, TEM, XRD, XPS, Mossbauer spectroscopy and thermal analysis (TGA/DTA). Three variations of MIC preparation modes were studied: wet mix in hexane of ferric oxide /aluminum, wet mix in hexane of ferric oxide xerogel /aluminum and xerogel of ferric oxide/aluminum. All variants were characterized using HRSEM, EDS, TEM, TGA/DTA and bomb calorimeter. The xerogel synthesized from ferric chloride hexahydrate precursor is characterized by bigger particle size and lower water molecule content. Primary particles of this xerogel are around 50-80nm. Xerogels synthesized from ferric nitrate nanohydrate precursor are less brittle, basic particles are around 5nm. Based on XRD and XPS characterization, the formed xerogel is Fe2O3 *nH2O with n>2. Additional drying of the xerogel at 350°c dehydrates some of the water from the molecule and partial crystallization occurs. I can conclude in this work that ferric nitrate nanohydrate precursor produces lower particle size xerogel and somewhat more energetic, what can be expected since lowering particle size contributes to higher surface and contact area between the aluminum fuel and ferric oxide oxidizer.