Low temperature synthesis of semiconducting α-Al2O3 quantum dots

A simple low temperature chemical route, which was based on the reactions of aluminium nitrate and hexamethylenetetramine in aqueous medium at 473 K for 36 h, was proposed for the synthesis of α-Al2O3 quantum dots (QDs). The characterisation results from X-ray diffraction, Fourier transform infrared spectroscopy and transmission electron microscopy along with selected area diffraction pattern are revealed the formation of α-Al2O3. Ultra-violet spectra indicated that the as-synthesised α-Al2O3 has a direct band gap of about 3.6 eV and also disclosed semiconducting behaviour of α-Al2O3 QDs using defect chemistry.