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Dependence of Rates of Interfacial Electron Transfer
on Anchoring Group
Debra L. Mohler, Department of Chemistry and Biochemistry,James Madison University
Interfacial electron transfer (ET) from molecular adsorbates and metal or semiconductor
nanoparticles/thin films is an essential process in applications including photocatalysis, solar energy
conversion, and photography. The emerging field of heterogeneous photocatalysis is of particular
interest for its potential to employ green methods in functionalizing petroleum-derived materials and in
developing new synthetic methods. Because the rate of ET is often a key determinant of efficiency in
these systems, the understanding of this process is essential for their design.
Absorbance change (mOD)
Absorbance change (mOD)
We have prepared seminconductor nanoparticles coated with molecules that each contain a different
group anchoring it to the nanoparticle; and these anchoring groups dramatically change the rate of ET.
Calculations reveal that these rates correlate with electronic coupling in molecular orbitals, which can
be thought of the highway for the electrons to move from the dye to the nanoparticle.
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X=-COOH
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X=-PO3H2
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