%0 Journal Article
%T Effect of pH, Surfactant, and Temperature on Mixed-Phase Structure and Band Gap Properties of BiNbO4 Nanoparticles Prepared Using Different Routes
%J -
%D 2019
%R https://doi.org/10.3390/chemistry1010008
%X ¦Á- and ¦Â-BiNbO 4 nanoparticles were successfully prepared using three different routes, namely co-precipitation, hydrothermal, and citrate precursor methods. Structural characterization has been analyzed using powder X-ray diffraction where results confirmed the mixed-phase nature of the prepared powders. When co-precipitation method is applied, BiNbO 4 prepared at pH 2 and calcined at 750 ¡ãC shows predominately the ¦Á-BiNbO 4 owning the narrowest band gap of 2.86 eV, whereas an increase in the pH value resulted in the ¦Â-BiNbO 4 phase being the predominant phase. On the other hand, samples prepared using citrate precursor method show co-existence of both ¦Á- and ¦Â-BiNbO 4 at all pH values under study; however, at pH 10 the ¦Â-BiNbO 4 was the dominant phase exhibiting a higher bandgap energy value of 3.16 eV. When applying the hydrothermal approach, BiNbO 4 prepared at all pH ranges of the present study show a band gap >3.2 eV indicating their activity in the ultraviolet region of the spectrum. Moreover, increasing calcination temperature to 900 ¡ãC, a gradual transformation of ¦Á- to ¦Â was observed. Lastly, it was noticed that as the lattice volume increases, the band gap of prepared BiNbO 4 decreases. View Full-Tex
%U https://www.mdpi.com/2624-8549/1/1/8