In the presented work the photoelectrochemical properties of SbSI along with the electronic
structure (i.e. conduction and valence band edge potentials as well as conductivity type) of
sonochemically obtained nanowires are discussed for the
fi
rst time. The spectroscopic
investigations indicate interesting optical properties, including surface isotope effect and
excitonic emission. The photoelectrochemical investigation of SbSI revealed the occurrence of
the photoelectrochemical photocurrent switching effect. It may be de
fi
ned as a change in
photocurrent direction (generated at the illuminated semiconducting electrode immersed in
electrolyte) due to an appropriate polarization of the electrode versus the reference electrode. It is
often observed for semiconductors as a result of the reduction of molecular oxygen dissolved in
the electrolyte. However, in the case of SbSI, the photocurrent switching was recorded regardless
of the presence of molecular oxygen in the electrolyte, probably due to the reduction of triiodide
species formed at anodic polarization of the SbSI electrode, in an iodide-containing electrolyte.
The switching potential (i.e. the potential where anodic-to-cathodic photocurrent transition
occurs) equals to ca. 0.4 V versus standard hydrogen electrode, which is close to the formal
potential of the I
−
/I
3
−
redox couple. Therefore, this semiconducting material is of potential interest
for the construction of new photovoltaic systems, novel optoelectronic switches and logic
devices.