Antimicrobial, anti-smudge dual-functional silica coating via interfacial chemical modification

Visual screens are susceptible to contamination from bacteria and smudges, while demanding high optical performance. Developing multifunctional coatings with anti-reflective, antibacterial, and anti-smudge properties is crucial to ensure optimal functionality and clarity. Herein, we developed a hydrophobic and antimicrobial SiO₂ antireflective coating by a two-component molecular chain synergistic strategy. The introduction of fluorosilane (FAS) components as defensive layer endowing the coating with hydrophobicity and significantly reducing bacterial and smudge adhesion to the surface. The quaternary ammonium salt (QAS) with positive charge of N⁺ facilitates the adsorption of negatively charged bacteria, disrupting their metabolism. The interplay between FAS and QAS was carefully tuned to achieve optimal performance. At the optimal state, the F_0.3/Q-SiO₂ coating exhibits an antimicrobial efficiency exceeding 99 %, along with a high WCA (>104°) and light transmittance (>93.4 %). Moreover, the coating demonstrates high mechanical durability, maintaining its optical clarity, anti-smudge properties, and antibacterial performance after 2000 wear cycles. This work demonstrates the synergistic effects of FAS and QAS in in enhancing antimicrobial properties, offering a promising solution for advanced visual screen applications requiring multifunctionality and durability.