Spray pyrolysis synthesis of TaxLi7-xLa3Zr2-xO12 nanostructured ceramic

Abstract

Abstract Li7-xLa3Zr2-xO12-Tax (x =0, 0.1, 0.2, 0.3) nanostructured powders were successfully synthesized using an innovative wet chemical route via spray pyrolysis technique at 800 °C for 10 seconds, followed by post heat treatment at 800 °C for 30 minutes in a muffle furnace. X-ray diffraction (XRD) analysis confirmed that Ta-doping increased the cubic phase up to 99%. Scanning Electron Microscopy (SEM) showed spherical particles with sizes ranging from slightly below 200 nm to 3 µm. The powders were then pressed at 50 MPa and sintered at 850 °C for 7 minutes using Spark Plasma Sintering, followed by post heat-treatment at 900 °C for 2 hours in a muffle furnace. XRD indicated the majority predominance of the garnet cubic phase, and SEM images showed coalescence and longitudinal growth of the particles, forming layers inside the samples. This study reports a fast synthesis and sintering method to obtain cubic garnet crystalline structure in contrast to conventional methods that are widely used and published in the literature, which require longer parameters in the synthesis stages (~24 hours) and sintering stages (over 12 hours).

Keywords

• garnet structure
• tantalum
• spray pyrolysis
• ceramic electrolyte
• lithium batteries