(Digital Presentation) Development of a Novel pH Sensor Based Polyaniline Supported on Nickel Modified Nickel Foam Electrode

Abstract

pH is an essential parameter that has to be regularly monitored in biological and environmental applications [1]. Typically, handling fragile electrodes and a number of calibration steps make the measuring process time-consuming. Polyaniline-modified electrodes have several advantages in terms of dependability, miniaturization, and cost-effectiveness, all of which are important features for in vivo applications.In this work, a hybrid material made of polyaniline, nickel, and nickel foam (PANI/Ni/NF) was combined together to detect H+ ions. First, using cathodic electrodeposition, nickel (Ni) was electrodeposited onto the surface of nickel foam (NF) [2]. Then, the surface of Ni/NF was modified by a self-assembled polyaniline (PANI) membrane to improve the ability of Ni to transform charges. SEM, EDX, Raman spectroscopy and XPS were used to characterize the morphology of PANI/Ni/NF. Fig. 1 shows SEM image of PANI on the surface of nickel oxide modified nickel foam electrode. Cyclic voltammetry (CV) and Open circuit potential (OCP) were used to monitor the potential shift based on different pH in the buffer solutions. The pH sensor displays the sensitivity of −46.00 mV/pH (R2=0.99) with stable performance in the physiological pH range from 3–11. This prototype has been tested along with a commercial pH meter on real samples (orange, baking powder solution). The durability and repeatability tests also show promising results. This porous and tiny pH sensor opens up new horizons for monitoring H+ in biological, environmental or wet laboratory based samples.AcknowledgmentsUniversity of Grants Commission of Bangladesh (2021-22) for funding this research.References F. Song et al., ACS Appl. Energy Mater., 2018, 1, 1, 3–8.M. Jamal et al., J. Electrochem. Soc., 2022, 169, 057517M. Jamal et al., Microsys t. Technol . , 2018, 24, 4217–4223. Fig. 1. SEM image of PANI modified Ni/NF Figure 1