In-situ ceramic nanoparticle assembly within wood microstructure for strong, tough, and resilient ceramic wood

Increasingly extreme environmental conditions demand structural materials that combine mechanical robustness with sustainability. Natural wood is renewable and mechanically adaptable but suffers from high porosity and hydrophilicity, leading to moisture absorption, fire vulnerability, and environmental degradation. Ceramics provide high stiffness, thermal stability, and chemical resistance but are inherently brittle. Here we report ceramic wood, a composite formed by integrating a natural wood scaffold with uniformly distributed ceramic nanoparticles. A calcium silicate precursor infiltrates the aligned nanofluidic channels of wood and undergoes in-situ self-assembly into calcium silicate hydrate nanoparticles under room-temperature conditions. The resulting ceramic network fills micropores and forms strong interfacial bonding within the wood scaffold. Ceramic wood exhibits high compressive strength, enhanced toughness, excellent fire resistance, and improved durability against moisture, fungi attack, and alkaline environments. CO₂ uptake further reduces the carbon footprint, highlighting ceramic wood as a sustainable structural material for extreme environments.