Tuning dissociation using isoelectronically doped graphene and hexagonal boron nitride: water and other small molecules

TL;DR

This study uses density functional theory to investigate how isoelectronic doping of graphene and hexagonal boron nitride enhances their reactivity, enabling the design of selective catalysts and membranes for small molecule dissociation.

Contribution

It introduces a framework for tuning the reactivity of 2D materials through isoelectronic doping, enabling selective interaction with polar or non-polar molecules.

Findings

Doped surfaces show increased reactivity compared to pristine materials.

Doping can be tailored to enhance selectivity towards specific molecules.

A general framework for dissociative adsorption on doped 2D materials is developed.

Abstract

Novel uses for 2-dimensional materials like graphene and hexagonal boron nitride (h-BN) are being frequently discovered especially for membrane and catalysis applications. Still however, a great deal remains to be understood about the interaction of environmentally and industrially elevant molecules such as water with these materials. Taking inspiration from advances in hybridising graphene and h-BN, we explore using density functional theory, the dissociation of water, hydrogen, methane, and methanol on graphene, h-BN, and their isoelectronic doped counterparts: BN doped graphene and C doped h-BN. We find that doped surfaces are considerably more reactive than their pristine counterparts and by comparing the reactivity of several small molecules we develop a general framework for dissociative adsorption. From this a particularly attractive consequence of isoelectronic doping emerges: substrates can be doped to enhance their reactivity specifically towards either polar or non-polar adsorbates. As such, these substrates are potentially viable candidates for selective catalysts and membranes, with the implication that a range of tuneable materials can be designed.