Chiral Nematic Cellulose Nanocrystal Films for Enhanced Charge Separation and Quantum-Confined Stark Effect.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 39381943.
- Also identified by DOI 10.1021/acsnano.4c04727 and PMC identifier 11503774.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Efficient charge separation is essential in various optoelectronic systems, yet it continues to pose substantial challenges. Building upon the recent evidence that chiral biomolecules can function as electron spin filters, this study aims to extend the application of chirality-driven charge separation from the molecular level to the mesoscale and supramolecular scale. Utilizing cellulose nanocrystals (CNCs) derived from cellulose, the most abundant biomaterial on Earth, this research leverages their self-assembly into chiral nematic structures and their dielectric properties. A device is introduced featuring a chiral nematic hybrid film composed of CNCs and quantum dots (QDs), decorated with iron oxide nanoparticles. Using the quantum-confined Stark effect (QCSE) to probe charge separation, we reveal significant sensitivity to the circular polarization of light and the chiral nematic structure of the film. This approach achieves effective, long-lasting charge separation, both locally and across length scales exceeding 1 μm, enabling potential applications such as self-assembled devices that combine photovoltaic cells with electric capacitance as well as optical electric-field hybrid biosensors.