Kathrine Frank

Purdue University

Project Title: Hydrothermal Processing of BST Powders
Advisor: Prof. Elliott Slamovich

Introduction

Traditional methods of ceramics processing involve high heat and high pressure. There is a growing demand for ceramics with particles less than 100 nm in diameter for microelectronic applications, and the particles produced in the conventional way are too large. This research focuses on an new method of processing barium strontium titanate to generate smaller particles.

Project Objectives

Determine the relationship between composition and particle size in hydrothermal processing of barium strontium titanate

Approach

  • Assemble BaCl2, SrCMl2, NaOH, and TiO2 powders, in amounts calculated to achieve specific ratios
  • Add powders to 100 mL of water
  • Let powders react for 48 hours in a oven heated to 80C
  • Rinse powders to remove contamination
  • Analyze powders with x-ray diffraction

Findings

Particle size is directly proportional to the mole fraction of barium in the powder. Between 70% and 100% barium, this relationship is approximately linear. The particles produced range from 39 to 100 nm in diameter.

It was observed that at higher pH's (higher NaOH concentration), particle size increased, but a definate mathematical relationship could not be inferred.


Fig. 1. Barium strontium titante, 53% mole fraction barium.
Fig. 2. Barium titanate.

Contact me: klfrank@purdue.edu