Hierarchical self-assembly of CdTe quantum dots into hyperbranched nanobundles: suppression of biexciton Auger recombination.

In this paper, we report a novel nanobundle structure formed by the hierarchical self-assembly of TGA-capped CdTe quantum dots. HR-TEM confirms the polycrystalline phase of the bundle structure, and that pristine quantum dots are the building units. The steady state absorption and luminescence properties of the pristine quantum dots can be well inherited by the nanobundles. In transient state observation, carrier quenching induced by Auger recombination is found to be remarkably suppressed. Electron delocalizing to close building units is considered to be the reason. Suppression of Auger recombination may earn much more time for charge separation, which makes the novel nanobundle structures suitable for the excellent donor material in solar cell applications.