All-Inorganic and Hybrid Capping of Nanocrystals as Key to Their Application-Relevant Processing
- PDF / 1,299,264 Bytes
- 8 Pages / 432 x 648 pts Page_size
- 101 Downloads / 164 Views
MRS Advances © 2018 Materials Research Society DOI: 10.1557/adv.2018.445
All-Inorganic and Hybrid Capping of Nanocrystals as Key to Their Application-Relevant Processing Vladimir Sayevich, Chris Guhrenz, and Nikolai Gaponik Physical Chemistry, Technische Universität Dresden, Bergstr. 66b, 01062 Dresden, Germany
Abstract
The design of the surface chemistry of colloidal semiconductor nanocrystals (NCs) presents a powerful synthetic approach that allows to tune the optical and electronic properties of the particles in independent and precisely desired manner, to provide chemical and colloidal stability in diverse media, and, finally, to control their targeted applicability ranging from catalysis, medicine to advanced electronic devices. In this article, we summarize the successful functionalization of colloidal NCs with specifically chosen ligands using a novel ligand-exchange strategy. To transform diverse colloidal NCs into a competitive class of solution-processed semiconductors for electronic applications, we replaced the pristine, insulating ligands with tiny inorganic and hybrid inorganic/organic species. The surface modification with inorganic ions modulates the charge carrier density in NC units and guarantees enhanced interparticle interactions. The subsequent functionalization of the allinorganic-capped NCs with organic molecules leads to the formation of hybrid inorganic/organic-capped NCs. For example, the introduction of short amine molecules enables to preserve the optical and electronic characteristics of their all-inorganic counterparts, while extending the solubility range and improving the ability to form longrange ordered 2D and 3D superstructures. Moreover, these short amines can be further used as convenient axillary co-ligands facilitating the surface functionalization of all-inorganic NCs with other biocompatible molecules, such as polyethylene glycol (PEG). This opens further perspectives for NCs not only in optoelectronic but also in biological and medical applications.
INTRODUCTION Based on the powerful synthetic routes for the preparation of semiconductor NCs with precisely controlled composition, size, morphology, and crystal phase homogeneity, nowadays, it is possible to create a broad range of novel functional materials with unique optical, electrical, and magnetic properties. Despite great improvements with respect to the understanding and controlling of multiple synthetic parameters, the practical implementation and real-world applicability of these crystalline materials that can successfully compete with existing technologies in areas such as quality lighting, (opto)electronics, and biology is still challenging [1]. The colloidal synthesis of diverse NCs is mainly performed in organic solvents with the aid of hydrophobic ligands with long hydrocarbon chains. These ligands control
Downloaded from https://www.cambridge.org/core. Cambridge University Main, on 26 May 2018 at 09:46:22, subject to the Cambridge Core terms of use, available at https://www.cambridge.org/core/terms. https
Data Loading...
