Transparent conductive films of pristine graphene can be formed through the spontaneous climbing of exfoliated graphene sheets onto hydrophilic substrates. When graphite is sonicated in a water/heptane mixture, the resulting interfacial exfoliation produces graphene sheets that remain pinned at the liquid-liquid interface. This interface extends to the surface of hydrophilic materials such as glass when exposed to the organic phase, enabling graphene sheets to climb substrate walls through interfacial forces.

The resulting films consist of overlapping graphene sheets with thickness limited to one to four layers, achieving up to 95% optical transparency while maintaining electrical conductivity. This method provides a scalable route to transparent conductive films without the chemical degradation associated with oxidation-reduction approaches.

Publications

Conductive Thin Films of Pristine Graphene by Solvent Interface Trapping
Woltornist, S.J.; Oyer, A.J.; Carrillo, J.-M.Y.; Dobrynin, A.V.; Adamson, D.H.
ACS Nano 2013, 7, 7062-7066

Foundational work demonstrating the formation of laterally macroscopic pristine graphene films with up to 95% transparency and conductivities of approximately 400 S/cm through interfacial assembly at water/heptane interfaces.

Transparent Conductive PEDOT–Graphene Films from Large-Flake Graphite
McDermott, S.T.; Ferland, B.; Liu, J.; Abeykoon, P.; Joyce, M.J.; Shuster, S.; Suib, S.L.; Adamson, D.H.
Synthetic Metals 2025, 312, 117866

Integration of SITM-exfoliated graphene with conducting polymers to create hybrid transparent conductors with enhanced performance, achieving conductivities up to 1070 S/cm while maintaining optical transparency.

Preparation of Conductive Graphene/Graphite Infused Fabrics Using an Interfacial Trapping Method
Woltornist, S.J.; Alamer, F.A.; McDannald, A.; Jain, M.; Sotzing, G.A.; Adamson, D.H.
Carbon 2015, 81, 38-42

Interface-Exfoliated Graphene-Based Conductive Screen-Printing Inks: Low-Loading, Low-Cost, and Additive-Free
Chen, F.; Varghese, D.; McDermott, S.T.; George, I.; Geng, L.; Adamson, D.H.
Scientific Reports 2020, 10, 18047

Graphene and Poly(3,4-ethylene dioxythiophene):Poly(4-styrenesulfonate) on Nonwoven Fabric as a Room Temperature Metal and Its Application as Dry Electrodes for Electrocardiography
Sinha, S.K.; Alamer, F.A.; Woltornist, S.J.; Noh, Y.; Chen, F.; McDannald, A.; Allen, C.; Daniels, R.; Deshmukh, A.; Jain, M.; Chon, K.; Adamson, D.H.; Sotzing, G.A.
ACS Applied Materials & Interfaces 2019, 11, 32339-32345