CdS|TiO2 Non-Enzymatic Sulfide Photoelectrochemical Sensor

A non-enzymatic photoelectrochemical detection of aqueous sulfide and ascorbic acid, using an CdS
$\vert $
TiO2 nanotubes photoanode, is presented. Its performance is compared with a CdS
$\vert $
Pt photoanode. Both the electrodes show high sensitivity in the visible range with capabilities of detection at micromolar levels for sulfide and ascorbic acid. Photoelectrodes are also able to detect micromolar levels of
$\text{H}_{{2}}\text{O}_{{2}}$
, but this analyte causes the degradation of CdS during photocurrent measurements, with the consequent release of Cd
$^{{2}+}$
ions to the analyte solution.