Water Interactions with Two-Dimensional Materials

Water profoundly influences the physical, chemical and electronic behaviour of atomically thin materials. At the interface between a two-dimensional (2D) sheet and its supporting substrate, water can form ordered hydration layers that modulate adhesion energy, charge screening and device stability. Capillary forces arising from nanoscopic water menisci affect both mechanical measurements and the performance of sensors and transistors under ambient conditions. The phenomenon of wetting transparency allows the underlying substrate’s hydrophilicity to determine the apparent contact angle of water on an otherwise inert monolayer. In parallel, computational and experimental studies have revealed that the strength and structure of water adsorption depend on surface chemistry, defects and atomic registry. Understanding these interfacial phenomena is critical for the design of humidity sensors, flexible electronics and catalytic platforms based on graphene, transition metal dichalcogenides and other emerging 2D materials.

Research from Nature Portfolio

Recent studies have employed atomically precise imaging to elucidate trapped hydration layers at the 2D interface. Using graphene as an impermeable cap on a hydrophilic substrate, researchers have revealed ordered ice structures and ion distributions influencing local charge transfer at the interface. Others have developed advanced dynamic atomic force microscopy models for transition metal dichalcogenide monolayers, demonstrating how capillary forces arising from nanoscopic water menisci affect height measurements and contrast inversion. These insights have refined our understanding of capillary interactions and measurement artefacts, informing best practices for the characterisation of 2D materials under ambient conditions.

Water Interactions with Two-Dimensional Materials publication trend

The graph below shows the total number of articles in water interactions with two-dimensional materials across all publications each year (not limited to Nature Index journals).

Technical terms

Capillary forces: Attractive interactions arising from liquid menisci at interfaces between a probe tip or substrate and a 2D material, significant at nanometre scales under humid conditions.

Hydration layer: Ordered molecular film of water confined between a two-dimensional material and its substrate, affecting adhesion, electronic screening and interfacial structure.

Wetting transparency: The phenomenon by which an atomically thin layer allows the wetting properties of the underlying substrate to dominate the observed contact angle of water on the 2D material.

Density functional theory (DFT): A quantum mechanical computational method used to model electronic structure and predict adsorption energies of water on 2D material surfaces.

Intercalation: The insertion of water molecules between a two-dimensional sheet and its supporting substrate or between layers of the same material under varying humidity.

References

1. Hydration layers trapped between graphene and a hydrophilic substrate. New Journal of Physics (2014).
2. Graphene Visualizes the Ion Distribution on Air-Cleaved Mica. Scientific Reports (2017).
3. Reduction in Step Height Variation and Correcting Contrast Inversion in Dynamic AFM of WS2 Monolayers. Scientific Reports (2017).
4. Water adsorption kinetics on graphene controlled by surface modification of supporting substrates. Nano Express (2024).
5. Understanding the wetting of transition metal dichalcogenides from an ab initio perspective. Physical Review Research (2023).
6. Humidity-controlled interactions and lifting of MoS2 on SiO2. Journal of Physics Materials (2025).