Eco-friendly geopolymer-wood building materials: Interactions between geopolymer and wood cell wall

Interactions between geopolymer and wood cell wall was investigated to better understand the bonding mechanism of geopolymer-wood composites as sustainable building materials. Elemental distributions, topological chemistry, and micro-mechanical properties between geopolymer and spruce wood cell wall were mainly investigated by the scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS), UV microspectrophotometry (UMSP), nanoindentation, and nanoscratch. It was discovered that lignin may migrate from the wood cell wall to the surface of the geopolymer and thereafter partially contribute to the production of the geopolymer without appreciably damaging the wood cell wall. Geopolymer mineralized and hardened the surfaces of wood cell walls (S3 and S2 layers) evidenced by the increasing H/E and H³/E² from spruce cell walls to geopolymer. The average width of the interaction region was around 7.65 μm according to different friction coefficients.