Strontium substituted bismuth and titanium oxide nanoparticles with aurivillius morphology synthesized by chemical
co-precipitation method and were characterized using XRD. The nanopartcles were used in the composition of the
carbon paste to improve conductivity and transduction of chemical signal to electrical signal. A procedure for the
determination of chromium is described based on pre-concentration of the dichromate anion at a carbon paste
electrode modified. A novel potentiometric Cr6+carbon paste electrode incorporating Strontium substituted bismuth
and titanium oxide nanoparticles (SSBTO). Ina acetate buffer solution of pH 5, the sensor displays a rapid and
linear response for Cr6+ over the concentration range 1.0×10-5 to 1.0×10-1mol L-1 M with an anionic slope of
54.8± 0.2 mV decade ’ and a detection limit of the order of0.002 /μg ml ‘. The sensor is used for determination of
Cr6+ by direct monitoring of Cr6+.The average recoveries of Cr6+at concentration levels of 0.5~40 pg/ml ’is 98.3.
The electrode has a short response time (<6s ) and can be used for at least twenty days without any considerable
divergence in potentials and the working pH range was 4.5-6.5. The proposed electrode was successfully used as an
indicator for potentiometric determination of Cr6+in water sample.
Keywords: potentiometric،nanoparticle،Strontium substituted bismuth and titanium oxide