Bioinspired valorisation of biomass into thermally stable superhydrophobic coating for self-cleaning and icephobic cotton fabric

Abstract

Superhydrophobicity is a centuries-old concept that has been rediscovered in the past decades, largely owing to understanding the mechanisms of special water-repelling phenomena in nature. In this study, we explore the environmental friendly, biomass-based approach to synthesise superhydrophobic (SHP) materials using pine cone, with minimum utilisation of harmful chemical compounds. A simple one-pot reflux method in the presence of 1-bromooctadecane and polar aprotic solvents led to the formation of functionalised SHP carbon materials with water contact angle (WCA) of 159°, 160°, 164°, and 167°. The grafting of the long-chain alkyl groups on the biomass-derived carbon material was further confirmed by FTIR, 13C NMR, and XPS. The SHP carbon material was utilised to fabricate the mechanically and thermally robust SHP-coated cotton fabric with a WCA of 164.5°. It shows the good thermal resistance up to 150°C and self-cleaning capabilities, removing dirt within 6 s. The coated fabric demonstrated icephobic properties, showing a significant delay in ice nucleation after 1hr at −10°C and rapid passive deicing to attain a stabilisation phase within 4 min. This simple, one-pot, and environmental friendly method can be applied to produce biomass-based SHP-coated fabric and shows excellent potential for expanding the field of SHP applications in harsh environments.