Photocatalytic Glucose Conversion with Selectivity Changes Using TiO2 Photocatalysts Synthesized by Modified Sol-Gel Method

Food products containing non-caloric sugars have become increasingly popular. Due to their potential health benefits for diabetes and a healthy diet. Non-caloric sugars have a taste very similar to sucrose, but are half as sweet and contain no or very few calories due to their absence from metabolic processes. Normally, non-caloric sugars such as arabinose and xylitol can be synthesized through a series of complex processes, such as acid hydrolysis or yeast fermentation of xylose. Photocatalysis is a green route technology that uses a photocatalyst and solar light to convert sugar to non-caloric sugar in a single step. Because of their stability, non-toxicity, and affordability, TiO₂ nanoparticles are used in a variety of photocatalytic applications. In this work, we demonstrate the successful fabrication of spherical TiO₂ using both standard sol-gel (SG) and modified sol-gel methods (sol-gel with ultrasonication (US) and microwave-assisted sol-gel) (sol-microwave, MW). The MW-TiO₂ demonstrated the highest glucose conversion of 64.8 % and the highest yield of non-caloric sugar of 35%, including 29% arabinose and 6% xylitol. Microwave irradiation can be used to shorten the synthesis time and produce small particles of TiO₂ with a high surface area. These properties contribute to the photocatalytic activity and yield of non-caloric sugars being enhanced.