Study on solar reflection and photocatalysis of titanium dioxide/tourmaline composite powder coating

Titanium dioxide (TiO₂), known for its high reflectivity, is extensively used in pigments, cosmetics, and photocatalysis. Sol-gel synthesized titanium dioxide particles are fine and uniform, yet expensive. Tourmaline, prone to agglomeration, forms larger particles that diminish its reflective capacity. Hence, this study employs the sol-gel method to disperse tourmaline with TiO₂, creating a composite powder with excellent dispersion, solar reflectivity, and degradation ability. The effects of varying ratios on these properties were investigated. The effects of varying ratios on these properties were investigated. ASTM G173 was used to determine the solar reflection of the composite powders, and all of them exhibited increased value. The highest improvement reaches approximately 19.3% and 18.8% compared to the individual base materials. In the IPA catalytic degradation experiment, the composite's bandgap (3.17 eV) is slightly narrower than pure TiO₂, extending light absorption toward the visible range and exhibiting the fastest acetone production rate of 212.24 μmol/h.