Nanoporous Triangulene-Based Frameworks for the Separation of Petroleum Hydrocarbons: Electronic, Magnetic, Optical, and Adsorption Properties

Abstract

Triangulene-based nanostructures have been recently synthesized in great variety, demonstrating exceptional physics and chemistry. Herein we investigate triangulene-based frameworks and their potential for the selective sorting of lightweight paraffins and olefins. Using first-principles calculations, we scrutinize the electronic, magnetic, and optical properties of triangulene-based nanostars considered to be building blocks of the frameworks. Decoration with Fe and Cu atoms and subsequent interaction with olefins (C2H4 and C3H6) and paraffins (C2H6 and C3H8) are further considered. It is found that the nanostars successfully bind with the chosen transition metals and demonstrate positive physical and chemical adsorption of the hydrocarbons before and after decoration. Adsorption energy and charge-transfer analysis show that metal nanostars are selective to olefins. The adsorption process allows for convenient tracking via UV–vis spectrometric tools, detecting a redshift as a characteristic signature of the adsorption of hydrocarbons. The reported complexes exhibit quick recovery times that ensure fast bind-release cycles and therefore a high gas separation performance suitable for large-scale applications.