Hydrothermal Synthesis of K(2)Ti(6)O(13) Nanotubes/Nanoparticles: A Photodegradation Study on Methylene Blue and Rhodamine B Dyes

[Image: see text] The degradation of methylene blue and rhodamine B dyes using potassium hexatitanate nanoparticles (KTNPs) and potassium hexatitanate nanotubes (KTNTs) synthesized via a hydrothermal method as efficient photocatalysts under UV light irradiation was investigated. The kinetics of degradation was determined for the two different catalysts––KTNPs and KTNTs––by monitoring the optical absorption of the dyes. The as-synthesized KTNPs were found to be spherical in shape with an average particle size of ∼36 ± 1.7 nm, whereas the KTNTs evidenced a tubular hollow structure with ∼7 nm internal diameter and ∼12 nm external diameter, as perused by structural and morphological studies. The larger surface area of KTNTs showed a greater impact on the photodegradation of dyes manifesting their high potential as compared to KTNPs under UV irradiation, and the reusability studies showed more than 90% (KTNTs) and 80% (KTNPs) degradation of the dyes even after the fourth cycle elucidating their stability.