Biosynthesis of gold nanoparticles using ethanolic propolis extract for methylene blue and Rhodamine-B removal

Abstract

• The green synthesis of gold nanoparticles (AuNPs) was done by propolis extract. • Photocatalytic degradation was performed using AuNPs under UV light. • AuNPs showed significant efficiency for methylene blue and Rhodamine B. The study proposed that gold nanoparticles (AuNPs) that were biosynthesized using propolis extract can degrade methylene blue (MB) and Rhodamine-B. First, the AuNPs were characterized using color change, electron microscopy, vis-UV spectroscopy, and Fourier-transform infrared (FTIR) analysis; then, the photocatalytic activity was measured under U.V. in various concentrations. The results showed a color change from yellowish to violet, indicating the reduction of Au 3+ to Au 0 . In addition, transmission electron microscopy (TEM) showed that the polydispersed shapes were in the nanoscale. Moreover, the biosynthesized AuNPs have high removal efficiency for MB and Rhodamine-B under U.V. irradiations. The implications of these findings proposed a new and sustainable method for the biosynthesis of AuNPs using the ethanolic propolis extract with the promising potential for removing contaminants in water.