Stability of a Rolled-Up Conformation State for Two-Dimensional Materials in Aqueous Solutions

TL;DR

This paper develops a universal model to predict the stability of 2D material scrolls in water, considering material properties and electrostatic forces, providing maps of stable and unstable configurations.

Contribution

It introduces a universal binding energy model based on material parameters and electrostatic effects, enabling stability prediction of 2D material scrolls in aqueous solutions.

Findings

Universal binding energy depends on material parameters and Hamaker coefficient.

Electrostatic double-layer repulsion can destabilize scrolls in water.

Stability maps identify conditions for stable and unstable scroll configurations.

Abstract

Two-dimensional (2D) materials can roll up, forming stable scrolls under suitable conditions. However, the great diversity of materials and fabrication techniques has resulted in a huge parameter space significantly complicating the theoretical description of scrolls. In this Letter, we describe a universal binding energy of scrolls determined solely by their material parameters, the bending stiffness, and the Hamaker coefficient. Aiming to predict the stability of functionalized scrolls in water solutions, we consider the electrostatic double-layer repulsion force that may overcome the binding energy and flatten the scrolls. Our predictions are represented as comprehensive maps indicating the stable and unstable regions of a rolled-up conformation state in the space of material and external parameters. While focusing mostly on functionalized graphene in this work, our approach is applicable to the whole range of 2D materials able to form scrolls.