Synthesis and characterization of rice grains like Nitrogen-doped TiO2 nanostructures by electrospinning–photocatalysis

Rice grain-shaped Nitrogen-doped titanium dioxide (N–TiO2) nano/mesostructures were fabricated through a combination of sol–gel and electrospinning methods. As-spun nanofibers were continuous and upon thermal treatment at 500° C for 1 h in air, the continuous fibers break into rice grain-shaped TiO2 nanostructures of average diameter 50–80 nm. The nanostructures were characterized by spectroscopy, microscopy and powder X-ray diffraction. The rice grains consist of spherical particles of average diameter of ~ 18 nm and with N doping, their average diameters decrease from ~ 18 to ~ 12 nm. The presence of N in the TiO2 lattice was confirmed by X-ray photoelectron spectroscopy (XPS). The band-gap of TiO2 reduced from 3.19 eV to 2.83 eV upon increasing doping level of N from 0% to 5% (w/w), respectively. The N–TiO2 rice grains showed an enhanced UV light-assisted photocatalysis compared to pure TiO2 in the photodegradation of Alizarin Red S dye, an industrially important anthraquinone dye.

Graphical abstractN-doped TiO2 rice grains like structures.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► N-doped TiO2 (N-TiO2) rice grain shapes are prepared by electrospinning. ► Nitrogen doping had confirmed by XPS and Raman spectral analysis. ► The rice grains were single crystalline and porous with a surface area of ~70 m2/g. ► N-TiO2 rice grains show a reduced band gap and enhanced UV-vis photoactivity. ► We anticipate that the material is best choice for photovoltaics.