One-Step Formation of Hybrid Nanocrystal Gels

Deposition of Metal Domains on CdSe/CdS Nanorod and Nanoplatelet Networks

authored by
Dániel Zámbó, Anja Schlosser, Rebecca T. Graf, Pascal Rusch, Patrick A. Kißling, Armin Feldhoff, Nadja C. Bigall

Hybrid semiconductor-based nanocrystals (NCs) are generally synthesized in organic media prior to their assembly into catalytically promising nanostructures via multistep methods. Here, a tunable, easy-to-adapt and versatile approach for the preparation of hybrid nanoparticle networks from aqueous nanocrystal solutions is demonstrated. The networks consist of interconnected semiconductor NC backbones (made of CdSe/CdS dot-in-rods or core/crown nanoplatelets) decorated with noble metal (Au and Pt) or with metal-based domains (Co2+ and Ni2+) demonstrating a powerful synthetic control over a variety of hybrid nanostructures. The deposition of the domains and the formation of the network take place simultaneously (one-step method) at room temperature in dark conditions without any external trigger. Beside the in-depth structural characterization of the gel-like hybrid networks, the wavelength-dependent optical features are studied to reveal an efficient charge carrier separation in the systems and a controllable extent of fluorescence quenching through the domain sizes. Photoluminescence quantum yields and decay dynamics highlight the importance of fine-tuning the conduction band/Fermi level offset between the semiconductors and the various deposited metals playing central role in the electron–hole separation processes. This procedure provides a novel platform toward the preparation of photo(electro)catalytically promising hybrid nanostructures (acetogels and xerogels) without the need of presynthetic hybrid particle design.

Institute of Physical Chemistry and Electrochemistry
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Advanced Optical Materials
Publication date
Publication status
Peer reviewed
ASJC Scopus subject areas
Electronic, Optical and Magnetic Materials, Atomic and Molecular Physics, and Optics
Electronic version(s) (Access: Open)