Multifunctional superhydrophobic composite films from a synergistic self-organization process

Abstract

A synergistic self-organization method was proposed to prepare multifunctional superhydrophobic composite films, which combined well-exfoliated graphene nanosheets (GNs) with a conjugate polymer (poly(3-hexyl thiophene), P3HT) through a simple solution-deposition process. The composite film can be rapidly prepared on various substrates; typically only a few minutes were necessary when the P3HT-GN suspension was coated on a metal mesh. The 35 wt% P3HT composite film is superhydrophobic with a contact angle of 159.2°, an electrical conductivity up to 6560 S m⁻¹ and specific electromagnetic interference shielding effectiveness (43.7 dB cm³ g⁻¹) four times greater than solid copper. It has a porous structure with the bulk density of 0.76 g cm⁻³, separation efficiency of over 98% for the n-octane/water mixtures in volume ratios of 1 : 1–1 : 15, and good environmental stability with a capacity to endure thermal treatment at 200 °C and organic solvents such as methanol, acetone and DMFetc. This synergistic self-organization method was also applied to prepare superhydrophobic P3HT-montmorillonite (MMT) composite films with a contact angle of 161° and a high adhesion capacity to water droplets, proving a versatile method in fabricating functional superhydrophobic films suited to practical applications.