Tetra-penta-deca-hexagonal-graphene (TPDH-graphene) hydrogenation patterns: dynamics and electronic structure

TL;DR

This study explores the hydrogenation process of a novel 2D carbon allotrope, TPDH-graphene, revealing how hydrogen incorporation alters its electronic properties and induces unique structural features.

Contribution

It provides new insights into the hydrogenation dynamics and electronic structure modifications of TPDH-graphene using DFT and molecular dynamics simulations.

Findings

Hydrogen atoms predominantly bind to tetragonal rings (up to 80% at 300 K).

Hydrogenation creates narrow bandgaps and Dirac cone-like electronic features.

Hydrogenation induces well-defined pentagonal carbon stripes.

Abstract

The advent of graphene has renewed the interest in other 2D carbon-based materials. Bhattacharya and Jana have proposed a new carbon allotrope, composed of different polygonal carbon rings containing 4, 5, 6, and 10 atoms, named Tetra-Penta-Deca-Hexagonal-graphene (TPDH-graphene). This unusual topology created material with interesting mechanical, electronic, and optical properties and several potential applications, including UV protection. Like other 2D carbon structures, chemical functionalizations can be used to tune their TPDH-graphene properties. In this work, we investigated the hydrogenation dynamics of TPDH-graphene and its effects on its electronic structure, combining DFT and fully atomistic reactive molecular dynamics simulations. Our results show that H atoms are mainly incorporated on tetragonal ring sites (up to 80% at 300 K), leading to the appearance of well-delimited pentagonal carbon stripes. The electronic structure of the hydrogenated structures shows the formation of narrow bandgaps with the presence of Dirac cone-like structures, indicative of anisotropic transport properties.