ELECTROSTATICALLY STABILIZED METAL SULFIDE NANOPARTICLES FOR COLORIMETRIC MEASUREMENT OF HYDROGEN SULFIDE

Methods and related apparatuses and mixtures are described for spectroscopic detection of hydrogen sulfide in a fluid, for example a formation fluid downhole. A reagent mixture is combined with the fluid. The reagent mixture includes metal ions for reacting with hydrogen sulfide forming a metal sulfide, and a solvent that stabilizes the metal sulfide nanoparticles and assist in preventing precipitation by electrostatic stabilization. The solvent includes a property having a density above 1 kg/l. Further, dissolving the metal ions into the solvent to create the reagent mixture, and mixing the reagent mixture with the hydrogen sulfide sample in a formation. So, the metal ions of the reagent mixture react with the hydrogen sulfide sample to form the metal sulfide nanoparticles, resulting in the metal sulfide nanoparticles having properties with a density from 1 kg/l to about 8 kg/l.