Hydrazine chemical sensing by modified electrode based on in situ electrochemically synthesized polyaniline/graphene composite thin film

The modified electrode of polyaniline/graphene (PANI/Gr) composites was prepared by in situ electrochemical synthesis of aniline monomer and graphene oxide in hydrochloric acid. The PANI/Gr composites modified electrodes were utilized for fabricating the highly sensitive, reliable and reproducible hydrazine chemical sensor. The PANI/Gr composites modified electrodes were extensively characterized by morphological, structural and the optical properties. The Raman studies revealed that PANI/Gr composite modified electrode possessed both Gr and PANI Raman bands, suggested the π–π* electron interaction between CN+ of PANI and carboxylate group of Gr. The sensing performance of the fabricated chemical sensor toward the detection of hydrazine was measured by a two electrode current–voltage (I–V) technique. A very high sensitivity of ∼32.54 × 10−5 A cm−2 mM−1 and reasonable detection limit of ∼15.38 mM with correlation coefficient (R) of 0.78578 and short response time (10 s) were observed by PANI/Gr composites modified thin film electrode.