Metal oxides having molecular and/or biomolecular functionalization
Disclosed herein are methods for functionalizing metal oxides, including tin dioxide. The methods comprise contacting at least one linker precursor comprising a first functional group to a metal oxide and exposing the linker precursor to UV light. The first functional group covalently binds to the metal oxide via a UV light induced reaction. The linker precursor may be an alkene having a vinyl group or an alkyne having an ethynyl group. Other molecules, such as biomolecules and dye molecules, may be bound to the linker precursors. The functionalized metal oxides may be used alone or as coatings on a substrate and find use in a variety of devices, including biosensors and dye sensitized solar cells.
1. A functionalized metal oxide comprising:
a metal oxide; and
at least one linker molecule covalently bound to the metal oxide via an anchoring group,
wherein the at least one linker molecule comprises the anchoring group, the anchoring group is a carbon, a CH group, or a CH 2 group, and the anchoring group is covalently bound directly to the metal oxide without any intervening atoms between the carbon of the anchoring group and the metal oxide,
and further wherein, the at least one linker molecule comprises a functional group and a dye molecule is covalently bound to the linker molecule via the functional group.
2. The functionalized metal oxide of claim 1 , wherein the functional group is selected from a protected or unprotected carboxylic acid group or a protected or unprotected amine group.
3. The functionalized metal oxide of claim 1 , wherein the at least one linker molecule is the reaction product of a linker precursor and the metal oxide, further wherein the linker precursor comprises a substituted or unsubstituted alkene or a substituted or unsubstituted alkyne, and further wherein the at least one linker molecule comprises a substituted or unsubstituted alkane, a substituted or unsubstituted alkane, a substituted or unsubstituted alkene, or a substituted or unsubstituted alkyne.
4. The functionalized metal oxide of claim 1 , wherein the metal oxide comprises doped or undoped TiO 2 , ZnO, ZrO 2 , or SnO 2 .
5. The functionalized metal oxide of claim 1 , wherein the metal oxide comprises a nanocrystalline, porous structure.
6. The functionalized metal oxide of claim 1 , wherein the metal oxide comprises a non-porous structure.
7. The functionalized metal oxide of claim 1 , wherein the metal oxide is disposed over the surface of a substrate.
8. The functionalized metal oxide of claim 7 , wherein the substrate is selected from glass or plastic.
9. A dye-sensitized solar cell comprising the functionalized metal oxide of claim 1 .
10. The functionalized metal oxide of claim 1 , wherein the at least one linker molecule is the reaction product of a linker precursor and the metal oxide, further wherein the linker precursor is a substituted or unsubstituted alkyne, and further wherein the at least one linker molecule is a substituted or unsubstituted alkene or a substituted or unsubstituted alkyne.
11. The functionalized metal oxide of claim 1 , wherein the metal oxide is patterned with an array, the array comprising one or more areas having the at least one linker molecule and one or more areas without the at least one linker molecule.
12. The functionalized metal oxide of claim 11 , wherein the at least one linker molecule in one area of the array is different from another linker molecule in another area in the array.