Zno/CuO nanocomposite-impregnated mangium wood with enhanced dimensional stability, preservative performance, and biological durability

Mangium (Acacia mangium) is a fast-growing wood species with relatively low durability and dimensional stability. This study investigated the effects of ZnO, CuO, and ZnO/CuO nanocomposites on the performance of treated mangium wood. ZnO nanoparticles were synthesised using a hydrothermal method, CuO nanoparticles by coprecipitation, and ZnO/CuO nanocomposites through solvent-assisted mixing. The ZnO/CuO-50 treatment produced the highest weight per cent gain (6.84%), retention (48.32 kg m−³), density (630 kg m−³), and bulking effect (4.81%), while reducing water uptake to 35.40%. Penetration testing confirmed extensive distribution of Zn²⁺ and Cu²⁺ ions within the wood structure, whereas SEM-EDS elemental mapping verified the presence and localisation of Zn and Cu throughout the treated specimens. The treated wood exhibited low leachability and enhanced biological durability, with ZnO/CuO nanocomposite treatments showing substantially lower weight loss during graveyard testing than untreated wood. XRD analysis revealed reduced wood crystallinity, indicating interactions between the nanocomposite system and the lignocellulosic matrix. Additionally, the retained photocatalytic activity toward methylene blue degradation demonstrated that the incorporated ZnO/CuO nanoparticles preserved their photoresponsivity functionality after impregnation. ZnO/CuO nanocomposite impregnation improved dimensional stability, preservative performance, and biological durability of mangium wood.