Synthesis, Properties, and Photocatalytic Activities of PbS/TiO2 Nanotubes

PbS quantum dots (PbS QDs) with tunable size were attached to TiO
₂
nanotubes both inside and outside the surface of the nanotubes by using thiolactic acid, a bifunctional linker. The size of the PbS QDs with diameters of 2-10 nm was controlled by adjusting the concentration of thiolactic acid. By first blocking the outer surface of the TNTs with the double-chain cationic surfactant, PbS QDs can be placed only on the inside of the nanotubes. The PbS/TiO
₂
nanotubes were characterized by TEM, as well as Raman, FT-IR, and UV-vis spectroscopy. The photocatalytic activities ofPbS/TiO
₂
nanotubes were evaluated for the photodegradation of organic dyes. Preliminary results indicate the functionalized TiO
₂
nanotubes were superior catalysts for photodegradation of cationic dyes.