Prolonging the combustion duration of wood by TiO₂ coating synthesized using cosolvent-controlled hydrothermal method

Thin TiO₂ coating was grown on wood surface using a cosolvent-controlled hydrothermal method. The surface morphology, chemical composition, and functional groups were examined by the scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDXA), and Fourier transform infrared spectroscopy (FTIR), respectively. The crystalline phase of TiO₂ was investigated by the X-ray diffraction (XRD). The combustion test was carried out on the Dual Analysis Cone Calorimeter, according to the fire testing standard ISO 5660-1. Resulted from the combined analysis of SEM and EDXA, FTIR and XRD, it was demonstrated that the anatase TiO₂ layer accompanying some spheral morphology chemically bonded to wood surface with intact and smooth appearance. The significant differences in combustion parameters between the untreated and the TiO₂ coated wood were observed. In comparison to the untreated wood, the burning time of TiO₂ coated wood was doubled, and the smoke, CO, CO₂ emissions were markedly reduced. As a result, the TiO₂ coating can effectively act as a protective layer to prolong the combustion duration of wood and prevent the harmful gas from spreading.