Integrating Long-Lasting Underwater Lubrication and Anti-Microbial Corrosion into A Semi-Solid Emulsion System Using Cu2O Nanosheet Surfactants.

Nanoparticle surfactants have shown great potential for developing semi-solid Pickering emulsion gels (PEGs), but achieving the application of gels under harsh marine conditions remains a challenge. Herein, water-in-oil lubricating and anti-microbial corrosion PEGs prepared by a simple and universal method are proposed. The mean coefficient of friction (CoF) of PEGs in artificial seawater is as low as 0.066, even after 719,300 friction cycles and under an external normal load of up to 200 N. Additionally, the PEGs containing amphiphilic Cu2O nanosheets (AC-NSs) exhibit outstanding long-lasting antibacterial activity against both Gram-positive (S. aureus) and Gram-negative (P. aeruginosa) bacteria, achieving antibacterial rates of 97.5 and 93.7% after 30 days, respectively. Notably, the PEGs establish anti-microbial corrosion protection through a synergistic effect of anti-swelling properties, physical barrier effects, and antibacterial activity. This work is anticipated to provide an effective strategy for constructing semi-solid emulsion systems using nanoparticle surfactants to achieve long-lasting lubrication and anti-microbial corrosion capabilities that prevent failure in marine equipment.