1 research outputs found
Quantitative Attachment of Bimetal Combinations of Transition-Metal Ions to the Surface of TiO<sub>2</sub> Nanorods
We
report the sequential, quantitative loading of transition-metal
ions (Cr<sup>3+</sup>, Mn<sup>2+</sup>, Fe<sup>2+</sup>, Co<sup>2+</sup>, Ni<sup>2+</sup>, and Cu<sup>2+</sup>) onto the surface of rod-shaped
anatase TiO<sub>2</sub> nanocrystals in bimetallic combinations (<sub>6</sub><i>C</i><sub>2</sub> = 15) to form M,M′-TiO<sub>2</sub> nanocrystals. The materials were characterized with transmission
electron microscopy (TEM), powder X-ray diffraction (XRD), elemental
analysis, X-ray photoelectron spectroscopy (XPS), and UV–visible
spectroscopy. TEM and XRD data indicate that the sequential adsorption
of metal ions occurs with the retention of the phase and morphology
of the nanocrystal. Atomistic models of the M,M′-TiO<sub>2</sub> nanocrystals were optimized with density functional theory calculations.
Calculated UV–visible absorption spectra and partial charge
density maps of the donor and acceptor states for the electronic transitions
indicate the importance of metal-to-metal charge transfer (MMCT) processes