Green synthesis of nano silver from euphorbia geniculata leaf extract: Investigations on catalytic degradation of methyl orange dye and optical sensing of Hg2+

Abstract

Plant mediated synthesis of metal nanoparticles has gained more importance due to its simplicity, rapid rate of synthesis, low cost of operation and environment-friendliness. The present article reports the synthesis of silver nanoparticles (AgNPs) from Euphorbia geniculata leaf extract (EugeAgNPs) and investigate their behaviour towards catalytic degradation of methyl orange (MO) dye and sensing of Hg2+ ions in solutions. Under the conditions of synthesis, the EugeAgNPs with an average size of about 17 nm were synthesized. Catalytic behaviour of these nanoparticles towards the reduction of MO dye by NaBH4 was also investigated. It was observed that the use of EugeAgNPs in reaction mixture has accelerated the reaction between MO dye and NaBH4 by about 102 times more than in their absence (0.95% to 97.28%) indicating that good catalytic activity of green synthesized EugeAgNPs. Further, the mercury sensing properties of synthesized EugeAgNPs were also examined. The results suggest that AgNPs obtained from Euphorbia geniculata leaf extract show excellent mercury sensing properties in the range 10 µg/mL to 120 µg/mL. Therefore, it was concluded that the AgNPs from Euphorbia geniculata leaf extract can be employed in catalytic degradation of industrial dyes as well as in optical sensing of mercury.