Abstract – This study describes the fabrication of three different gap-fingered aluminum-interdigitated electrodes (AlIDEs) on the silicon substrate based on photolithographic method, followed by integration of the gold nanorod–zinc oxide nanocomposite. The IDE masks were designed using AutoCAD software with the gaps of 10, 20, and 30 μm for design 1, 2, and 3, respectively. The morphological and electrical characterizations were subsequently performed using 3D-nanoprofiler, atomic force microscopy, high-power microscopy (HPM), scanning electron microscopy (SEM), and I–V. Validation of the fabricated surfaces (AlIDEs with/without gold nanorod–zinc oxide nanocomposite) against the electrolytes was performed at different pHs which are ranging from 1 to 12. SEM revealed the following gaps, 18.4, 20, and 40.5 μm for bare 1, 2, and 3, respectively. The measurements on I–V for bare AlIDEs indicated the electrolyte influences at different pH solutions, which were almost similar in terms of current variations except at highly acidic and alkaline. AlIDEs were well fabricated and the smaller the gap displayed the better the sensitivity, hence device 1 AlIDE has a good performance. Using different pH solutions which ranging from pH 1–12, before and after AlIDEs were coated with zinc oxide and gold nanorod. The responses of the devices were similar, fluctuating from highly acidic region to highly alkaline region in the cases of AlIDEs bare 1 and 3. Bare 2 AlIDE displayed similar responses with the AlIDE that was deposited with gold nanorod. With these results, we can conclude that deposition of gold nanorod on the device brought about the orderly response to the different pH and with the increment from acidic to alkaline increases, the proportional changes with the current were noticed.

Corresponding Author: Assoc. Prof. Dr. Subash C B Gopinath
Corresponding Author’s Email: subash@unimap.edu.my

Download: PDF