Fig. 3
The Fe3+ selective electrode characterization; A Calibration graph, B The dynamic response time of the for step changes in the concentration of iron solution: (a) 1.0 × 10−6 M, (b) 1.0 × 10−5 M, (c) 1.0 × 10−4 M, (d) 1.0 × 10−3 M, (e) 1.0 × 10−2 M and (f) 1.0 × 10−1 M. C The pH effect of the sample solutions on the potential response. D Potentiometric titration curve of iron ion (1.0 × 10−3 M, 50 mL) with standard EDTA solution (1.0 × 10−2 M) using fabricated electrode based on b-18C6 as an indicator electrode at 25 °C