Vapor phase synthesis of hexagonal shaped single crystal yttria stabilized zirconia nanoparticles using CO2 laser

Growth of hexagonal shaped single crystal yttria stabilized zirconia nanoparticles has been observed in the vapors emanating from solid targets vaporized using CO₂ laser in CW and pulsed modes of operation. The mean size and yttrium concentration in these nanoparticles are found to be in the range of 5–40 nm and ～10.4–11.6 wt% respectively, which depend on the laser power density and the gaseous environment used during the growth process. Nanoparticles synthesized with pulsed mode of laser operation were found to be smaller in size compared to those generated in the CW mode. It was also found that formation of these nanoparticles was more pronounced in helium gas environment compared to those in nitrogen and argon. X-ray and electron diffraction studies showed that in all experimental conditions the generated nanoparticles were in cubic phase. From high resolution TEM it was observed that the nanoparticles with identical orientations coalesced with each other in line with the oriented attachment theory.