The uniqueness of physical and chemical natures of graphene: their coherence and conflicts

TL;DR

This paper explores the dual physical and chemical nature of graphene, highlighting their harmony and conflicts through molecular theory, and discusses how substrate deposition may stabilize its properties.

Contribution

It provides a detailed analysis of the molecular theory of graphene, clarifying the conflicts between its physical and chemical characteristics and proposing substrate deposition as a stabilization method.

Findings

Graphene's properties stem from odd electron correlation and high instability.

Substrate deposition can inhibit electron correlation, stabilizing graphene.

Chemical and physical properties of graphene can both align and conflict, depending on conditions.

Abstract

Molecular-crystalline duality of graphene ensures a tight alliance of its physical and chemical natures, each of which is unique in its own way. The paper examines the physical-chemical harmony and/or confrontation in terms of the molecular theory of graphene. Chemistry that is consistent with graphene physics expectations involves: small mass of carbon atoms, which provides a lightweight material; sp2 configuration of the atoms valence electrons, ensuring a flat 2D structure of condensed benzenoid units; high strength of C-C valence bonds responsible for exclusive mechanical strength. Chemistry that is in conflict with graphene physics expectations covers: radical character of graphene material; collective character of electronic system of graphene, preventing from localization of its response on any external impact; the molecular nature and topochemical character of graphene mechanics; the molecular nature of graphene magnetism. Each of the properties is a direct consequence of the odd electron correlation, on one hand, and ensures a high instability of graphene material, on the other. Electron correlation inhibition by deposition of graphene monolayers on substrates is seen as a promising way to solve the problem.