Medha Aekka
Research Mentor(s): Richard Laine
Mentor Department: Materials Science and Engineering
Authors: Medha Aekka, Richard Laine, Zeyu Yi
Session: Session 6 (3:00pm – 3:50pm)
Presentation Type: Poster 58
Abstract
As technology advances, it is becoming more and more important to find materials that are inexpensive and exhibit high performance. High Entropy Nitrides (HENs) combine five or more elements into a uniform simple crystallographic lattice (e.g. FCC) that offers improved properties none of the elements possess individually. Their enhanced thermal stability, mechanical strength, and electrical conductivity make them ideal candidates for a variety of applications, including coatings, catalysts, and electronic devices. However, existing synthesis methods are often costly or complex. This project aims to develop a simpler, more cost-effective technique of synthesizing HENs to improve accessibility and scalability. The proposed approach starts by synthesizing precursors to the nitrides. A metal propionate or isobutyrate is dissolved in acetonitrile and hexamethyldisilazane ([(CH3)3Si]2NH, or HMDS) at 70°C. The metals used were manganese, yttrium, iron, vanadium, and nickel, all of which form nitrides. During this process, the metal reacts with the HMDS, and forms bonds with its (CH3)3Si groups. This creates a metal-MDS compound which is stable and volatile, ideal for the remainder of the procedure. Additionally, the material is completely liquid, ensuring a homogeneous solution that will shape the desired uniform crystal structure. The product is vacuum-dried and heated in a furnace to create mixed metal nitrides. The formation of HENs were confirmed via various characterization techniques, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray diffraction (XRD). FTIR is used to determine the composition of the substance, TGA tests decomposition and thermal stability, and XRD is used to evaluate the crystalline structure of the product. The developed strategy successfully produced high-entropy nitrides with the desirable structural properties. This new synthesis method offers a simpler, economical approach for producing HENs, potentially allowing for greater integration into real-life applications in place of toxic or expensive materials.
