Uncovering Aggregation‐Induced Emission in Carbon Dots for Color‐Changing Hydrogels and Information Encryption
Abstract
ABSTRACT Since the discovery of carbon dots (CDs), the typical precursor combination of citric acid (CA)‐urea has been widely used in the scientific community to explore the formation mechanism and luminescence behavior of CDs. However, there have only been a few reports on the synthesis of CDs featuring aggregation‐induced emission (AIE) characteristics. In this study, CA and urea were used to synthesize hydrophilic red‐emissive carbon dots (R‐CDs) that exhibit blue fluorescence in water (dispersed state) and red fluorescence in DMF (aggregated state). The study reveals that the photoluminescence of R‐CDs is governed by π–π stacking interactions between solute molecules as well as solvent effects between solute and solvent molecules, leading to solvent‐responsive emission behavior. By tuning the solvent polarity, the intermolecular distance between R‐CDs can be adjusted, thereby influencing their photoluminescent properties. Taking advantage of the solvent‐responsive color change, anticounterfeiting printing and information encryption applications were designed. Moreover, by combining R‐CDs with poly(vinyl alcohol) (PVA), hydrogel‐based fluorescent information‐encoding materials were successfully fabricated.
Article Details
Authors (12)
Jiafeng Wan
Institute For Chemical Technology and Polymer Chemistry (ITCP) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Shiyi Chen
Key Laboratory for Green Chemical Technology of the Ministry of Education, School of Chemical Engineering and Technology, Institute of Molecular Plus, National Industry-Education Platform for Energy Storage
Haopu Su
Institute of Organic Chemistry (IOC) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Tim Muschik
Institute For Chemical Technology and Polymer Chemistry (ITCP) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Tongtong Cui
Institute For Chemical Technology and Polymer Chemistry (ITCP) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Yosuke Akae
Institute For Chemical Technology and Polymer Chemistry (ITCP) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Dominik Voll
Institute For Chemical Technology and Polymer Chemistry (ITCP) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Christian W. Schmitt
Soft Matter Synthesis Laboratory – Institute For Biological Interfaces III (IBG‐3) Karlsruhe Institute of Technology (KIT) Eggenstein‐Leopoldshafen Germany
Stefan Bräse
Institute of Biological and Chemical Systems–Functional Molecular Systems, Karlsruhe Institute of Technology
Tao Chen
Andreas‐Neil Unterreiner
Institute of Physical Chemistry (IPC) Karlsruhe Institute of Technology (KIT) Karlsruhe Germany
Patrick Théato
Karlsruhe Institute of Technology (KIT), Institute for Chemical Technology and Polymer Chemistry (ITCP), Engesserstraße 18, 76131 Karlsruhe, Germany