Synthesis of an amphibious superamphiphilic carbon-based materials with unique properties

Abstract

Recently, superamphiphilic materials have attracted significant attention because of their excellent affinity towards both water and oil. In this study, a novel but simple strategy to endow carbon cloth and polyurethane (PU) foam with amphibious superamphiphilicity (i.e., superamphiphilicity simultaneously in air and in a pre-wetted state) has been demonstrated. Results showed that the surface wettability of the carbon cloth changed from hydrophobic to superamphiphilic by increasing the acidification time using HNO₃, which manifested the contact angle of 0° for water and oils irrespective of the state (at dry state or pre-wetted with water or oil) under which the surface was put. Subsequently, the superamphiphilic PU foam was fabricated based on a simple acidification method, and possessed an excellent superamphiphilicity with water and oil fluids taking less than 19 seconds to spread completely on the surface when the PU foam was in a dry state or pre-wetted with water or oil. Moreover, the PU foam exhibited a high storage capacity for water and oil, up to 9–12 times of its own weight. The discovery of this superamphiphilic foam will provide a versatile and effective way for the development of superwetting materials and their applications in self-cleaning and anti-fouling fields.