Sensitive amperometric determination of hydrazine using a carbon paste electrode modified with silver-doped zeolite L nanoparticles

Silver-loaded nanozeolite-L-modified carbon paste electrode (Ag/L-CPE) was used as a novel sensing platform for enhanced electrocatalytic oxidation and determination of hydrazine. Zeolite L nanoparticles were synthesized via hydrothermal approach and then characterized using various techniques such as X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electronic microscopy (SEM) and Brunauer-Emmett-Teller (BET). Silver-exchanged nanozeolite L (Ag/L) was prepared and mixed with carbon paste to prepare the modified electrode. Cyclic voltammetry studies revealed the high performance of Ag/L-CPE for electrocatalytic oxidation of hydrazine. Two linear ranges were detected in the amperometric detection of hydrazine. The first range was from 10 mu M to 0.4 mM with sensitivity of 103.13 mu A mM(-1) and the second one was from 0.4 to 4 mM with sensitivity of 58.131 mu A mM(-1). The response time and detection limit (S/N = 3) of this sensor were determined to be 2 s and 1.5 mu M, respectively. The unique porous structure of nanozeolite L offers a promising catalyst support candidate for efficient electrochemical sensing of hydrazine. The sensor exhibited appreciable repeatability, reproducibility and stability, and was able to detect hydrazine in the presence of even 500-fold excess concentrations of interfering species. Also, the sensor was used to determine hydrazine concentration in water samples with satisfactory results.