A crystallization method for preparation of anatase-based glass-ceramic glaze

Developing a way to prepare effective, durable and high-temperature stable anatase-based photocatalytic ceramic is of great significance. In this work, we report a crystallization method for the preparation of anatase-based glass-ceramic glaze. The raw materials were made into frit and glazed on ceramic bodies. The glazed ceramics were sintered at 1180 degrees C and soaked at 700 degrees C. The effect of soaking temperature on the crystallization process was investigated. The photocatalytic property of the glazed tiles was evaluated by degradation of methyl orange. Experimental results show that after sintering and soaking at 700 degrees C, nanosized anatase grains crystallize in glaze. The crystallization of anatase nanograins is attributed to the relatively high viscosity at crystallization temperature. HF etching makes more anatase grains exposed on the surface. The sample etched for 45 s shows the highest photocatalytic activity and the methyl orange is decomposed by about 90% after illumination for 35 h.