TiO₂@C core@shell nanocomposites: A single precursor synthesis of photocatalyst for efficient solar water treatment

This study reports the facile synthesis of highly photoactive TiO₂@C core@shell nanocomposites through a single alkoxide precursor. TiO₂ and carbon-based hybrid nanomaterials are popular photocatalysts owing to their abundance, low toxicity, and high stability, making them strong candidates for practical solar water-treatment applications. However, synthesis of such nanomaterials is often a multi-step process and requires careful control of the external carbon source for producing the desired morphology. In this regard, this study reports the synthesis of well-dispersed TiO₂@C nanocomposites without the need of an external carbon source. The resulting photocatalyst was employed for treatment of various water-borne pollutants including several dyes, pharmaceuticals, and pathogens. Rapid mineralization of pollutants could be achieved even with low amounts of catalyst, with the performance well exceeding that of pristine TiO₂ and P25 Degussa. Results indicate that incorporation of C increases visible-light absorption and greatly improves the separation of photogenerated charge carriers. Given the facile synthesis and the wide scope of operation, the proposed catalyst could be a significant step towards practical photocatalytic solar water-treatment.