Graphenylene Nanoflakes: A Promising Platform for Toxic Gas Detection.

Gas monitoring, especially for toxic gases, is essential for various applications, including environmental pollution detection, industrial process control, and safety systems. In this regard, two-dimensional (2D) materials have attracted significant interest due to their unique electronic and structural properties, which can be tailored to enhance interactions with the target molecules. In this context, graphenylene nanoflakes, a porous 2D material, emerge as promising candidates due to their unique hexagonal network structure and tunable electronic properties. In this study, we use a Density Functional Theory based method to investigate theoretically the adsorption of various analytes, including some toxic gases, on graphenylene nanoflakes functionalized with transition metals (TMs). Our goal is to evaluate the adsorption capabilities of these graphenylene-based systems and how this adsorption affects the optical absorption spectrum, enabling the material to function as a gas sensor. Our results indicate that the adsorption energies of the selected analytes are significantly higher than those observed in TM-doped graphene flakes, suggesting stronger interactions. Furthermore, in certain cases, the adsorptions led to noticeable changes in the optical absorption spectra, paving the way for gas detection based on such effect. These findings can contribute to the development of new graphenylene-based sensing platforms with enhanced sensitivity and selectivity.