Electro-Determination of Protonation by Tungsten Anchored Carbon Nanoparticle on Interdigitated Gold Electrode

Abstract

This study presented an enhanced sensitivity of sensing protons (H+) by anchoring tungsten to carbon nanoparticles (WCN) to encourage high current density on the surface of gold interdigitated electrode (AuIDE). The morphology of the sensor evidences the intactness of electrode surface and suitable for WCN modification. To elucidate the study, unmodified AuIDE was compared to the WCN modified surface. Current-volt analysis was compared with electrolyte scouting in the variation of pH by using a picoammater, which supplied 0.0 to 2.0 V with a 0.1 V ramp interval. It was shown that modified WCN gave the sensitivity in the acidic medium (protons) at the pH 4 with a current density value of 2.5 × 10-5 ampere and increased further with lowering the pH to more acidic. This is due to the fact that the tungsten carbon nanoparticle that is anchored offering more electron density and alters the behavior of the chip. Meanwhile, the current density displayed insignificant changes of current density amplification from pH 5 to 12 with the range of 5.91 × 10-9 to 7.36 × 10-8 Ampere. The deposition of WCN on the AuIDE surface chip revealed the successfulness of this nanoparticle in chemically linked with the AuIDE surface and how modified nanoparticle altered the behavior of the sensing element.