Silver-doped superhydrophobic carbon soot coatings with enhanced wear resistance and anti-microbial performance

Abstract

In spite of the substantial interest and ongoing research in the field of superhydrophobicity, the wide daily-life usability of extremely water repellent coatings is somehow impeded due to the insuperable (currently) market requirements for simultaneous possession of cost-effectiveness, profitability, scalability and long-term durability. Carbon soot, seemingly worthless substance linked primarily with the disquieting climate changes, is gaining increasing popularity as an inexpensive and inherently hydrophobic material combining multifunctional properties such as non-wettability, icephobicity, optical permeability and anti-bioadhesiveness. In this article, we suggest a simple spray coating procedure for the development of novel silver-doped soot coatings with enhanced wear resistance and anti-microbial performance. The inclusion of silver hydrogen fluoride (AgHF2) in a soot-rich ethanol solution, and its sequential spray deposition on 200 °C heated glass slides, transforms the soot into an organometallic compound capable of retaining structural integrity, excellent surface adhesion and superhydrophobicity under finger-wiping and high-impact water jetting (∼25 m/s). Furthermore, the as prepared soot coatings show good degree of wear resistance towards sandpaper abrasion, remain free of attached bacteria, slowdown the proliferation of various Gram-negative bacterial strains and exhibit satisfactory long-term durability after 105 days of prolonged residence in sea water, promoting the possibility for future “on-field” studies.