Determination of the pH sensitivity level of anodized Ta2O5 nanotubular using pH buffer solution: Towards engine oil deterioration sensor

Tantalum is a potential material for metal anodizing, which enables the fabrication of ideal nanostructured Ta
2
O
5
. This project planned to employ Ta
2
O
5
, an anodized metal oxide, as a chemical sensor application. In the field of Ta
2
O
5
research, there is a lack of investigation into Ta
2
O
5
efficacy for the detection of engine oil deterioration. In this project, the objective is to fabricate Ta
2
O
5
nanotubular as sensing layers for the detection of engine oil deterioration. The Ta
2
O
5
sensor was fabricated through the anodization synthesis method and was then tested with 2, 4, 7, 10, and 12 pH buffer solutions. Anodization is very reliable for building nanostructures as it is easy to be manipulated. Samples were characterized using field emission scanning electron microscope (FESEM) for surface morphology and structural analysis, and their crystalline properties by X-ray diffraction (XRD). The output voltage was plotted over time, and the pH sensitivity of anodized Ta
2
O
5
was reported. As the result, the sensitivity sensor obtained for both 30 min and 60 min anodized samples were 31.616 mV/pH and 24.591 mV/pH, respectively, while the response time was obtained for rise time and fall time was 20 seconds and 90 seconds, respectively.