6533b82ffe1ef96bd1294850

RESEARCH PRODUCT

Electron tunneling from colloidal CdSe quantum dots to ZnO nanowires studied by time-resolved luminescence and photoconductivity experiments

Tobias VossFriederike AlbrechtStephanie BleyMichael DiezMargit ZachariasSiegfried R. WaldvogelAndreas MenzelJürgen GutowskiSebastian Resch

subject

PhotocurrentCondensed Matter - Materials SciencePhotoluminescenceMaterials scienceCondensed Matter - Mesoscale and Nanoscale Physicsbusiness.industryPhotoconductivityMaterials Science (cond-mat.mtrl-sci)FOS: Physical sciencesSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsGeneral EnergyQuantum dotExcited stateMesoscale and Nanoscale Physics (cond-mat.mes-hall)MoleculeOptoelectronicsPhysical and Theoretical ChemistrybusinessLuminescenceQuantum tunnelling

description

CdSe quantum dots (QDs) with different organic linker molecules are attached to ZnO nanowires (NWs) to study the luminescence dynamics and the electron tunneling from the QDs to the nanowires in time-resolved photoluminescence (PL) and photoconductivity measurements. The PL transients of the QD luminescence indicate two different recombination channels: the direct recombination inside the QD core and the recombination via QD surface defect states. After linking the QDs to the ZnO NW surface, photo-induced electron tunneling from an excited state of the QD into the conduction band of the nanowire becomes visible by a clear decrease of the PL decay time. Efficient electron tunneling is confirmed by a strong enhancement of the photocurrent through the functionalized nanowires in which the tunneling rate can be controlled by using different organic linker molecules.

https://dx.doi.org/10.48550/arxiv.1502.03279