Regulating the Electron Depletion Layer of Au/V₂O₅/Ag Thin Film Sensor for Breath Acetone as Potential Volatile Biomarker

Abstract

Human exhaled breath has been utilized to identify biomarkers for diseases such as diabetes and cancer. The existence of these illnesses is indicated by a rise in the level of acetone in the breath. The development of sensing devices capable of identifying the onset of lung cancer or diabetes is critical for the successful monitoring and treatment of these diseases. The goal of this research is to prepare a novel breath acetone sensor made of Ag NPs/V2O5 thin film/Au NPs by combining DC/RF sputtering and post-annealing as synthesis methods. The produced material was characterized using X-ray diffraction (XRD), UV-Vis, Raman, and atomic force microscopy (AFM). The results revealed that the sensitivity to 50 ppm acetone of the Ag NPs/V2O5 thin film/Au NPs sensor was 96%, which is nearly twice and four times greater than the sensitivity of Ag NPs/V2O5 and pristine V2O5, respectively. This increase in sensitivity can be attributed to the engineering of the depletion layer of V2O5 through the double activation of the V2O5 thin films with uniform distribution of Au and Ag NPs that have different work function values.

Keywords

• acetone
• gas sensors
• thin films
• exhaled breath
• biomarker
• depletion layer