Spectrophotometric analysis of stability of gold nanoparticles during catalytic reduction of 4-nitrophenol

Authors : Farhat SAİRA, Samia SALEEMI, Humaira RAZZAQ, Rumana QURESHI

Pages : 82-91

View : 21 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Spectrophotometric monitoring of 4-nitrophenol insert ignore into journalissuearticles values(4-NP); reduction by sodium borohydride insert ignore into journalissuearticles values(NaBH4); using gold nanoparticles insert ignore into journalissuearticles values(GNPs); as a catalyst has been extensively studied, but the stability of GNPs in terms of change in the surface plasmon resonance insert ignore into journalissuearticles values(SPR); at different temperatures has not been explored. In the present investigation, our aim was to evaluate the SPR stability of GNPs as a catalyst during the reduction of 4-NP at different elevated temperatures insert ignore into journalissuearticles values(i.e. 30-60 degrees C); and sodium borohydride concentrations. Sensitivity of this degradation process toward concentration of GNPs at a range of temperatures is also evaluated. The spectrophotometric results reveal that up to 45 degrees C, 12 +/- 1.5 nm catalyst has a consistent optical density insert ignore into journalissuearticles values(OD); during the entire 4-NP reduction process, which is related to the surface integrity of catalyst atoms. As the temperature approached 50 degrees C, the OD gradually decreased and showed a blue shift as the reaction proceeded, which could be related to a decrease in particle size or surface dissolution of gold atoms. The present study may find application in the design of catalysts for the reduction of organic pollutants in industrial wastewater at a range of temperatures.
Keywords : Spectrophotometry, gold nanoparticles, surface plasmon resonance, optical density, rate constant