Sunlight-powered total green synthesis of silver nanoresonators from aqueous extract of soybean (Glycine max) chunks: A highly specific colorimetric probe for H2S

[Display omitted] •A silver nanoprobe through total green synthesis having full water compatibility.•A wide pH window of 3–13.•The instant color change with H2S/Na2S.•The detection limit lies to the submicromolar level.•The recovery percentage of H2S in two spiked real samples viz., pond water and sewage water are 99 % and 106 % respectively. We report herein a total green synthesis of silver nano resonators having 43.77 nM concentration with their most frequent average size of ∼ 17 nm. The reaction mixture comprising of aqueous extract of soybean (Glycine max) chunks (15 mL) and AgNO3 (1 mL, 0.1 M) in a 100 mL round bottom flask was irradiated with sunlight for 3 hrs to bring out this synthesis. The as prepared AgNPs were fully characterized through various spectroscopic (FTIR & UV–Vis) and microscopic (SEM, TEM, SAED, EDX, AFM and DLS) studies. The same AgNPs were further exploited for highly selective detection and determination of a janus faced analyte like H2S from its aqueous solution at submicromolar level (LOD 7.39×10-7 M). The H2S is known for its role as one of the gaso-neurotransmitters in humans beside playing dubious role towards our environment. Two spiked real samples of water from pond and sewage were subjected for determination of their H2S content against these AgNPs, showed recoveries of 99 % and 106 % respectively.