Semiconductor nanostructures such as CdSe@CdS nanorods have already proved to be ideal photosensitizers for photocatalytic applications. Not only do their high absorption coefficients allow for efficient harvesting of solar light, but also their structure promotes efficient and long-lived charge separation: Upon photon excitation, an electron-hole pair is generated with the hole quickly localizing in the CdSe core and the electron, which is delocalized over the entire rod, can be transferred to a catalyst coupled to the nanorod tip. There, proton reduction can occur. [1,2]
We are currently focusing our efforts on aligning CdSe@CdS nanorods on a transparent, conductive surface, i.e., ITO glass, for the construction of a photoelectrode in a full watersplitting cell: While the electron is transferred to the catalytic center located at the nanorod tip and used for hydrogen reduction, the hole could be transferred to a counter electrode, where it may oxidize water to generate molecular oxygen. To this end, the nanorods have to be aligned on the surface under retention of their anisotropic properties. Two different approaches, namely electrophoretic deposition and interfacial self-assembly, are discussed and compared.

Financial support is acknowledged by the German Research Foundation (DFG) – project number 364549901 - TRR234 [CataLight, B4)] and the Fonds der Chemischen Industrie (FCI).

[1] M. Wächtler, P. Kalisman, L. Amirav, J. Phys. Chem. C 2016, 120, 24491–24497.
[2] Y. Nakibli, Y. Mazal, Y. Dubi, M. Wächtler, L. Amirav, Nano Lett. 2018, 18, 357–364.