Contact angle measurements on superhydrophobic Carbon Nanotube Forests : effect of fluid pressure

TL;DR

This study investigates how pressure affects water contact angles on superhydrophobic carbon nanotube forests, demonstrating their robustness and potential for microfluidic applications due to a simple functionalization method.

Contribution

The paper introduces a new functionalization strategy for superhydrophobic CNT forests and demonstrates their ability to withstand high pressures without losing hydrophobicity.

Findings

Surfaces withstand pressures over 10 kPa without roughness invasion.

The functionalization process is low-cost and simple.

Superhydrophobic properties are maintained under high pressure.

Abstract

In this paper the effect of pressure on the contact angle of a water drop on superhydrophobic Carbon Nanotube (CNT) forests is studied. Superhydrophobic CNT forests are obtained from a new and simple functionalization strategy, based on the gold-thiol affinity. Using a specifically devised experimental setup, we then show that these surfaces are able to withstand high excess pressures (larger than 10 kPa) without transiting toward a roughness-invaded state, therefore preserving their low adhesion properties. Together with the relatively low technical cost of the process, this robustness versus pressure makes such surfaces very appealing for practical integration into microfluidic systems.