Nitrogen doped nanohoops as promising CO2 capturing devices

Abstract

The impact of climate change in the face of steady or increasing emissions has made the capture and storage of CO₂ a priority issue. Supramolecular chemistry is one of the tools that can be used for this task, due to the possibility of tuning intermolecular interactions for the capture of this gas in a selective and efficient way. In this context, this work presents a novel approach for the capture of CO₂ based on n-cycloparaphenylenes ([n]-CPPs) doped with nitrogen atoms. This is the first time that the potential of these structures for the capture of polluting gases has been evaluated. Among all the structures analysed, the one yielding the best results (complexation energy of −32.80 kJ mol⁻¹) contains 4 nitrogen atoms per monomer. The topology of the electron density of the host–guest complex and the nature of its non-covalent interactions have been analyzed in this work in order to explain this high binding energy and identify potential structural modifications to improve it. The capability of this system to be used as a sensing device for CO₂ using vibrational spectroscopy is also explored.