Geopolymer applications in deep-sea energy and mining infrastructure: a review of properties, challenges, and future prospects

The advancement of deep-sea energy and mining operations—often at depths exceeding 1,000 m and pressures up to 400 bar—necessitates materials capable of withstanding extreme geomechanical, thermal, and chemical conditions. Traditional materials like Ordinary Portland Cement (OPC) exhibit limitations in such environments, including susceptibility to chloride ingress, sulfate attack, and thermal degradation. Geopolymers, synthesized through the alkali activation of aluminosilicate precursors, have emerged as promising alternatives, offering compressive strengths up to 100 MPa, thermal stability up to 800 °C, and ultra-low permeability levels as low as 10⁻¹⁸ m². Moreover, their production can reduce CO₂ emissions by up to 80% compared to OPC. This review assesses the current state of geopolymer technology in subsea applications, including hydrocarbon extraction, gas hydrate recovery, seabed mining, carbon capture and storage (CCS), and hydrogen storage. Key challenges identified include optimizing formulations for cold seawater environments, ensuring reliable underwater settings, and validating long-term performance under marine burial conditions. These results contribute to the ongoing research into sustainable building materials, providing valuable information on the ability of nano and advanced geopolymers to withstand environmental exposure and serve as a durable solution for corrosion management in marine infrastructure to develop resilient and sustainable deep-sea energy and mining.