l -Lysine-Assisted Synthesis of ZrO2 Nanocrystals and Their Application in Photocatalysis

Nanocrystalline ZrO 2 with narrow size distribution and mean size ∼8 nm has been synthesized by the l -lysine-assisted hydrothermal method. The structural and morphological characterizations were studied by powder X-ray diffraction (XRD) and transmission electron microscopy (TEM), and physicochemical characterizations were carried out by using infrared spectra (IR), UV−vis spectra, and photoluminescence (PL) spectra. On the basis of the choice of synthesis parameters, monoclinic (m-) and tetragonal (t-) phases of ZrO 2 coexisted with a size ∼8 nm. This is an important result with respect to application in catalytic properties of nanocryalline ZrO 2 . The possible nucleation and growth process is also discussed.