Quantitative Attachment of Bimetal Combinations of Transition-Metal Ions to the Surface of TiO2 Nanorods.
Choumini BalasanthiranStephanie JensenCharles S SpanjersShelton J P VarapragasamRobert M RiouxDmitri S KilinJames D HoefelmeyerPublished in: Langmuir : the ACS journal of surfaces and colloids (2018)
We report the sequential, quantitative loading of transition-metal ions (Cr3+, Mn2+, Fe2+, Co2+, Ni2+, and Cu2+) onto the surface of rod-shaped anatase TiO2 nanocrystals in bimetallic combinations (6 C2 = 15) to form M,M'-TiO2 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'-TiO2 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.
Keyphrases
- transition metal
- aqueous solution
- density functional theory
- electron microscopy
- quantum dots
- high resolution
- energy transfer
- visible light
- molecular dynamics
- room temperature
- molecular dynamics simulations
- single molecule
- metal organic framework
- solar cells
- electronic health record
- dual energy
- computed tomography
- mass spectrometry
- magnetic resonance imaging
- solid state
- magnetic resonance