Dear All,

You are invited to the seminar in the Department of Materials Science and Engineering.

Speaker: Assoc. Prof. Dr. Özge Balcı, Koç University, College of Sciences, Department of Chemistry

Title: Synthesis and catalytic/magnetic applications of boron-based functional nanoparticles

Date: Tuesday, November 01, 2022

Time: 10:30

Place: Engineering Faculty D Block, Seminar room (1st Floor)

Synthesis and catalytic/magnetic applications of boron-based functional nanoparticles
Having a combination of superior chemical, physical and mechanical properties has made transition metal borides of dire importance in various scientific and industrial fields. These properties can be significantly improved when the particle sizes decrease below 200 nm range. Hence, the preparation of nanocrystalline metal borides is quite challenging. Metal boride nanoparticles based on elements of Fe, Co and Ni gained increased attention in recent years as promising materials for catalytic and magnetic applications. In this talk, low-temperature synthesis routes including mechanochemical synthesis and inorganic molten salt technique for obtaining Fe-, Co-, and Ni-boride based metal boride nanoparticles will be presented. The low-temperature synthesis methods enabled the simultaneous formation of nanocomposite structures and caused a uniform morphology with average particle sizes and surface areas of 60-70 nm and 30-45 m2/g, respectively. As-synthesized Fe-Ni-B and Co-Ni-B particles were used as nanocatalysts in the hydrolysis reaction of NaBH4 to generate hydrogen as a renewable energy source. The activation energy of the hydrolysis reaction significantly decreased up to 32-40 kJ/mol, while the catalyst performed good durability during reusability tests. Thus, metal boride containing nanopowders are suitable catalyst alternatives for highly efficient and controllable hydrolysis reaction of sodium borohydride, as high-performance, reusable and low-cost materials. On the other hand, as-synthesized Co-Fe-B nanoparticles were investigated for their changing magnetic properties such as ferromagnetism and superparamagnetism. To acquire novel magnetic nanoparticles with high performance, it is aimed to tune the magnetic properties and increase the magnetization through optimizing the synthesis conditions. These functional nanoparticles can be potential candidates for magnetic drug targeting and electromagnetic sensors. Results show that metal boride nanoparticles are high-tech boron-based materials with a high potential in multi-functional areas including energy, biomedical and electronic applications.