Development of chromium(III) selective potentiometric sensor by using synthesized triazole derivative as an ionophore

A new poly(vinyl chloride) membrane based electrochemical sensor containing synthesized triazole compound,that is,bis-(4-n-amino-5-mercapto-1,2,4- triazol-3-yl)alkane (bamta) as an electroactive material was prepared and investigated as a chromium(iii) selective sensor. the optimum composition of the best performing membrane contained triazole,sodium tetraphenylborate (natpb),nitrophenyl octyl-ether (npoe),and polyvinyl-chloride (pvc) in the ratio 10: 2: 50: 38 w/w. the sensor exhibited near nernstian slope of 19.8±0.2 mv/decade of activity in the working concentration range of 1.0×10 -5-1.0×10 -1 m. it displayed a stable potential response in the ph range 3.4-5.2. the sensor exhibited a fast response time of less than 10 s and could be used for at least 6 weeks without any considerable divergence in potentials. the proposed sensor showed very good selectivity over most of the common cations including li +,k +,na +,ni 2+,co 2+,cu 2+,sr 2+,ba 2+,cs +,pb 2+,zn 2+,mg 2+,cd 2+,al 3+,fe 3+,and la 3+. it could be employed successfully for the determination of cr(iii) ion activity in electroplating and leather tanning industry wastes. © 2013 pankaj kumar et al.