Low-Cost Paper Electrode Fabricated by Direct Writing with Silver Nanoparticle-Based Ink for Detection of Hydrogen Peroxide in Wastewater

A simple, low cost and user-friendly method for the fabrication of paper electrode (PE) using silver nanoparticles capped with octylamine (AgNPs-OA) is reported for detection of hydrogen peroxide (H₂O₂) in wastewater samples. The PE was prepared by direct writing onto the photo paper using a ball-point pen filled with nanoink (10 wt % of AgNPs-OA in chloroform). The prepared electrode was sintered at 100 °C for 1 h to make it conductive. The PE/AgNPs-OA was used as a working electrode in cyclic voltammetry (CV) for the detection of H₂O₂. The PE/AgNPs-OA exhibited a wide linear calibration range from 1.7 μM to 30 mM for the determination of H₂O₂ with a low limit of detection, 0.5 μM. The good recovery percentage (95.2-96.2%) and interference study for determination of H₂O₂ in wastewater samples demonstrated the selectivity of the method from the complex sample matrices. The PE/AgNPs-OA electrode is found to be economic, facile and user-friendly for multiple analyses (n = 60) of H₂O₂ in CV compared to other commercially available electrodes and custom-made modified electrodes.