Characterization and reactivity of chromia nanoparticles prepared by urea forced hydrolysis
2008
Gulley-Stahl, Heather J. | Schmidt, Whitney L. | Bullen, Heather A.
Chromia (Cr₂O₃) nanoparticles were prepared by urea forced hydrolysis in the presence of chromium (III) nitrate using NaCl as a precipitating agent. The size, distribution, and purity of the particles were evaluated. The necessity of polyvinylpyrrolidone (PVP) as a surfactant to prevent aggregation was also investigated. In the presence of PVP, non-aggregated spherical-like nanoparticles (3 ± 1 nm) were formed, whereas in the absence of PVP, spherical-like weakly agglomerated nanoparticles (85 ± 16 nm) comprised of 10 nm nanoparticle subunits were produced, creating a large surface area. The as-formed hydrated Cr₂O₃ nanoparticles were amorphous, although they could be easily converted into crystalline form by heating to 400 °C for 1 h, with minimal particle aggregation and size reduction. Attenuated total reflectance Fourier transform infrared spectroscopy indicated that preparation methods (surfactant and precipitating agent) influence surface reactivity of the nanoparticles to catechol.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library