Multiple hydrogen bonds enhancing formaldehyde adsorption on functionalized zigzag graphene nanoribbons

Abstract

In this work, based on density functional theory, the edge and the center of both armchair-edged graphene nanoribbons (AGNRs) and zigzag-edged graphene nanoribbons (ZGNRs) have been modified through five oxygen-containing groups (epoxy, methoxy, formyl, hydroxyl and carboxyl) to form functionalized AGNRs and ZGNRs, in which distorted surface of AGNRs can be observed. Computational results indicated that ZGNR is appealing choice to act as a candidate for designing formaldehyde (HCHO) sensor. Simulation results demonstrate that the interactions between HCHO and oxygen-containing ZGNRs were mainly determined by the multiple hydrogen bonds. The novel design of carboxyl modified ZGNRs on the center of surface with the largest adsorption energy of − 0.510 eV and the relatively long recovery time of 4.15 × 10-4 s could act as a physical sensor to detect HCHO molecules. Dynamics simulation results indicated that HCHO shows very strong hydrogen bonding interactions during competitive adsorption with N2 and O2 at 298.15 K and 308.15 K. Consequently, simulation results offer a molecular-level insight into the interactions between HCHO and functionalized ZGNR surfaces, and might provide useful information for the design of HCHO sensors.