Synthesis and Mechanical Properties of Na0.7Coo2
Materials comprised of large Na0.7CoO2 nanosheets were made through a novel nanomanufacturing technique. This technique is based on sol-gel processing followed by electric-field induced kinetic-demixing and high temperature calcination. Demixing conditions play a vital role in the sheet growth. Kinetic demixing under different temperatures (300–500ºC), electrical currents of 500 mA and 750 mA, and duration times between 0-60 hours were tested to establish relationships between kinetic demixing conditions and the length of sheets. An embedding and polishing method was developed for this fragile material. The hardness and reduced modulus of Na0.7CoO2 with nanolayered structure are reported for the first time based on nanoindentation tests. The correlation between the mechanical properties and the structure of the nanolayered materials is reported. A deformation mechanism for nanolayers is suggested based on layer sliding. Aging problems associated with this material are also reported for the first time.
Nanosheets; Thermoelectric; Materials Science; Mechanical; Na0.7CoO2
Baker, Shefford P.
Robinson, Richard Douglas
Materials Science and Engineering
M.S., Materials Science and Engineering
Master of Science
dissertation or thesis