Supramolecular Chemistry of Carbon‐Based Dots Offers Widespread Opportunities

Abstract

Carbon dots are an emerging class of nanomaterials that has recently attracted considerable attention for applications that span from biomedicine to energy. These photoluminescent carbon nanoparticles are defined by characteristic sizes of <10 nm, a carbon‐based core and various functional groups at their surface. Although the surface groups are widely used to establish non‐covalent bonds (through electrostatic interactions, coordinative bonds, and hydrogen bonds) with various other (bio)molecules and polymers, the carbonaceous core could also establish non‐covalent bonds (ππ stacking or hydrophobic interactions) with π‐extended or apolar compounds. The surface functional groups, in addition, can be modified by various post‐synthetic chemical procedures to fine‐tune the supramolecular interactions. Our contribution categorizes and analyzes the interactions that are commonly used to engineer carbon dots‐based materials and discusses how they have allowed preparation of functional assemblies and architectures used for sensing, (bio)imaging, therapeutic applications, catalysis, and devices. Using non‐covalent interactions as a bottom‐up approach to prepare carbon dots‐based assemblies and composites can exploit the unique features of supramolecular chemistry, which include adaptability, tunability, and stimuli‐responsiveness due to the dynamic nature of the non‐covalent interactions. It is expected that focusing on the various supramolecular possibilities will influence the future development of this class of nanomaterials.

Zero-Dimensional Carbon Nanomaterials for Fluorescent Sensing and Imaging

“…Additionally, hydrogen bonding, which is the proton transfer between the electronegative atom (acceptor) and H atom (donor) connected with another electronegative atom. , Furthermore, charge–dipole and dipole–dipole interactions are attractions and repulsions between dipoles and formal charges. , Moreover, hydrophobic interactions are the entropy-driven aggregation of nonpolar solutes in polar solvents. In addition, charge−π, lone pair−π, and π–π interactions are the transitions of the formal charge, electron lone pair, and π–electron-rich systems to another π–electron-rich system. − According to these mechanisms, these processes are mainly based on oxygen- and nitrogen-containing functional groups and the sp 2 -hybridized conjugated system. , Therefore, amino-, carboxyl-, and hydroxyl-containing substances and π-conjugated systems, such as carboxylic acids, amides, amines, hydrazine, urea, hydrazones, oximes, crown ethers, cyclodextrin, calixarene, calixpyrroles, calixazoles, cucurbituramides, and columnar aromatic hydrocarbons are extensively employed. − …”

Carbon Dots‐Assisted Rapid Synthesis of Polypyrrole with High Uniformity for Efficient Solar‐Driven Water Evaporation

“…These features promise wide applications of CDs. [22][23][24] The underlying but probably more important advantage of CDs is their excellent capability to integrate with other materials to form composites with more superior performances. [25][26][27] This could be understood as follows.…”

Synthetic Strategies for the Selective Functionalization of Carbon Nanodots Allow Optically Communicating Suprastructures

“…For example, the surface groups on CNDs were widely explored to establish non-covalent bonds, such as electrostatic interactions, coordinative bonds, and hydrogen bonds with various other molecules and materials. [7][8][9] Otherwise, covalent derivatization has been exploited to finely modify the particle surface, anchoring the desired species to the CNDs. [10] The so-developed functional materials have as ultimate goal the preparation of valuable nanohybrids in which the merging of the intrinsic traits of the coupled constituents paves the way to advanced applications within the fields of optoelectronics, photovoltaics, medicinal chemistry, among others.…”