Single-Step Synthesis of LaMnO3/MWCNT Nanocomposites and Their Photocatalytic Activities

Composites of the nano-sized perovskite-type oxide of LaMnO3 and multi-walled carbon nanotubes (MWCNTs) were synthesized in a single step using the sol-gel method. Their photocatalytic activities for the degradation of various water-soluble dyes under visible light were evaluated. The prepared samples were characterized by thermogravimetry analysis, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, photoluminescence spectroscopy and UV-vis diffused spectroscopy. Results showed that LaMnO3 nanoparticles grew on the surface of MWCNTs with a grain size of around 20 nm. Photocatalysis measurements revealed that the LaMnO3/MWCNT nanocomposites had greater photocatalytic activities than pure LaMnO3 nanoparticles, and the mass percentage of MWCNTs showed that 9.4% possessed the highest photocatalytic activity. These results indicate that LaMnO3/MWCNT nanocomposites are promising candidates as highly effective photocatalysts.