CdSe Quantum Dot–Fullerene Hybrid Nanocomposite for Solar Energy Conversion: Electron Transfer and Photoelectrochemistry

다국어 초록 (Multilingual Abstract)

<P>The development of organic/inorganic hybrid nanocomposite systems that enable efficient solar energy conversion has been important for applications in solar cell research. Nanostructured carbon-based systems, in particular C<SUB>60</SUB>, offer attractive strategies to collect and transport electrons generated in a light harvesting assembly. We have assembled CdSe–C<SUB>60</SUB> nanocomposites by chemically linking CdSe quantum dots (QDs) with thiol-functionalized C<SUB>60</SUB>. The photoinduced charge separation and collection of electrons in CdSe QD–C<SUB>60</SUB> nanocomposites have been evaluated using transient absorption spectroscopy and photoelectrochemical measurements. The rate constant for electron transfer between excited CdSe QD and C<SUB>60</SUB> increased with the decreasing size of the CdSe QD (7.9 × 10<SUP>9</SUP> s<SUP>–1</SUP> (4.5 nm), 1.7 × 10<SUP>10</SUP> s<SUP>–1</SUP> (3.2 nm), and 9.0 × 10<SUP>10</SUP> s<SUP>–1</SUP> (2.6 nm)). Slower hole transfer and faster charge recombination and transport events were found to dominate over the forward electron injection process, thus limiting the deliverance of maximum power in CdSe QD–C<SUB>60</SUB>-based solar cells. The photoinduced charge separation between CdSe QDs and C<SUB>60</SUB> opens up new design strategies for developing light harvesting assemblies.</P><P><B>Graphic Abstract</B>
<IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2011/ancac3.2011.5.issue-12/nn204350w/production/images/medium/nn-2011-04350w_0010.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn204350w'>ACS Electronic Supporting Info</A></P>