Inhibition of Sulfate-reducing Bacteria Presence in Masonry via High-Performance Sol-Gel Coatings

Abstract

Microbially Influenced Corrosion (MIC) of concrete infrastructure accounts for a significant portion of the $2.5 trillion annual global cost of metal and concrete degradation. Existing MIC mitigation relies on epoxy barriers or antimicrobial admixtures that often fail due to poor interfacial bonding or pose a significant environmental risk. This study evaluates a novel hybrid organic-inorganic sol-gel coating designed to create a chemically integrated, antimicrobial shield. Comparative testing was deployed to examine the antimicrobial performance of Sol-158-3. While each test demonstrated a significant bacterial presence, Sol-158-3 maintained a stable, low microbial profile throughout testing. This presents a proactive strategy for mitigating microbial in masonry, effectively eliminating MIC. Notably, the pure sol-gel outperformed a sample modified with the biocide IPBC, suggesting that the structural density of Sol-185-3’s network is more critical for MIC resistance than secondary organic additives. By inhibiting early-stage neutrophilic colonization and maintaining surface alkalinity, this sol-gel intervention effectively disrupts the biogenic sulfur cycle. These findings provide a sustainable, cost-effective pathway for extending the service life of critical masonry infrastructure.