One-step synthesis of nanocrystalline ZnO via cryomilling

• Published in: Powder technology 2013-02, Vol.235, p.395-399
• Main Authors: Fabián, M., Tyuliev, G., Feldhoff, A., Kostova, N., Kollár, P., Suzuki, S., Saito, F., Šepelák, V.
• Format: Article
• Language: English
• Subjects: absorption; air; Applied sciences; Ball mills; Chemical engineering; Cryomilling; Crystallization, leaching, miscellaneous separations; Exact sciences and technology; Fourier transform infrared spectroscopy; Grinding; Miscellaneous; Nanocrystals; Nanoparticle; Nanoparticles; Nitrogen; oxidation; Powder technology; powders; Reactors; Semiconductor; Shells; Solid-solid systems; wavelengths; X-ray diffraction; X-ray photoelectron spectroscopy; Zinc; Zinc oxide; ZnO
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2012.10.049

In this work, the ZnO spherical nanoparticles with a diameter in the range of 10–30nm have been prepared via mechanochemical oxidation of metallic Zn powders treated in a vibratory ball mill in the presence of air and liquid nitrogen. The as-prepared nanocrystals were characterized by XRD, HR-TEM, FTIR, XPS, and UV–vis spectroscopy. The results show that metallic zinc powder is completely converted to nanocrystalline ZnO within 48h of cryomilling. The XPS analysis confirms the presence of incorporated nitrogen as well as Zn(OH)2 and carbonate species formed on the reactive structurally-disordered surface shell of the as-prepared nanoparticles. Compared with the pure ZnO, the light absorption by the as-prepared ZnO nanocrystals was shifted to longer wavelengths. Nanocrystalline ZnO consisting of an ordered core surrounded by a disordered surface shell region has been synthesized via cryomilling of metallic Zn in presence of air and liquid nitrogen. The presence of incorporated nitrogen as well as hydroxyl and carbonate species formed on the reactive structurally-disordered surface shell of the as-prepared nanoparticles has been confirmed. [Display omitted] ► The nanocrystalline ZnO has been synthesized via cryomilling of metallic Zn. ► The size of as-prepared nanoparticles is about 15nm. ► The XPS analysis confirms the presence of Zn in 2+ state. ►The light absorption by the as-prepared ZnO is shifted to longer wavelenghts.