Microsensor for total dissolved sulfide (TDS).
Chemosphere
; 323: 138229, 2023 May.
Article
en En
| MEDLINE
| ID: mdl-36841451
Total Dissolved Sulfide (TDS) concentrations can either be derived from simultaneous measurement of pH and one of the sulfide species or determined indirectly in samples following an acidification step. Here we report a microsensor that allows for direct measurement of TDS in aquatic media without the need for pH monitoring. An acidic chamber placed in front of a commercial, amperometric H2S microsensor allows for the in-situ conversion of dissolved ionic sulfide species to H2S, which in turn is oxidized at the transducer anode. A typical sensor had a tip opening of 30 µm, a response time of <50 s and linear range between 0.5 and 650 µM. The sensor performance can be largely tuned by altering the geometry of the chamber. Sensors of different sensitivity (0.04-2.93 pA/µM) showed no noticeable change in zero current and sensitivity during continuous polarization over 7 weeks. The sensor was successfully applied to resolve microscale TDS gradients in freshwater and marine sediments. Other avenues of application include the online monitoring of industrial and urban sewers.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Sulfuro de Hidrógeno
Idioma:
En
Revista:
Chemosphere
Año:
2023
Tipo del documento:
Article
País de afiliación:
Dinamarca
Pais de publicación:
Reino Unido