Glycine-fueled solution combustion synthesis: photocatalytic activity of bismuth oxide on the degradation of organic dye molecules in relation to differences in fuel-oxidant ratio

Bismuth oxide is a semiconductor metal oxide that can be synthesized by the solution combustion method. The purpose of this research is to synthesize bismuth oxide pertaining to variations in the fuel-oxidant ratio and determine the characteristics and the photocatalytic activity of bismuth oxide for the degradation of organic dye molecules including remazol black B, methyl orange and rhodamine B. The resulting products synthesized with the three ratios phi > 1, phi = 1, and phi < 1 were in the form of yellow powder. Fourier-transform infrared spectroscopy results of the three samples showed the presence of Bi-O-Bi and Bi-O functional groups indicating that Bi2O3 was formed. Moreover, X-ray diffractogram indicated that Bi2O3 particles contained in all samples were a mixture of alpha-Bi2O3 and beta-Bi2O3 phases. Coral reef-like morphology was observed in all samples with Bi2O3 phi = 1 having the smallest particle size followed by phi > 1 and phi < 1. Furthermore, Bi2O3 with phi > 1, phi = 1, and phi < 1 have band gaps of 2.584, 2.581 and 2.625 eV, respectively. The photocatalytic activity test showed that bismuth oxide synthesized with the ratio phi = 1 showed the best photocatalytic activity compared to phi > 1 and phi < 1 in the three different organic dye molecules, namely remazol black B, methyl orange, and rhodamine B.

Automated summary

This study focused on synthesizing bismuth oxide using the solution combustion method and investigating the effects of fuel-oxidant ratio on its characteristics and photocatalytic activity. The results showed that the band gap and photocatalytic activity of bismuth oxide were influenced by the fuel-oxidant ratio.