AuNP modified hetero-nanocomposite based chemicapacitive sensor for detection of ascorbic acid

Abstract

Human health requires ascorbic acid, an antioxidant. Its anomalies can cause many diseases. Therefore, a sensitive, rapid, and non-invasive approach is needed to detect these fluctuations on-site. This work presents an UV assisted hydrothermally synthesized AuNP decorated ZnO-rGO nanocomposite based chemicapacitive sensor. The sensing material is verified from its distinctive characteristics acquired using UV–Vis spectroscopy, X-ray diffraction, scanning electron microscopy and energy diffraction X-ray spectroscopy, providing evidence of its successful synthesis. Extensive experiments examine the sensor’s chemicapacitive response to 0.25–20 ppm ascorbic acid. The sensor exhibits a remarkably low detection limit of 0.3 ppm and an exceptional sensitivity of 0.93 µF/ppm, fast response time (minimum 8 s to a maximum of 37 s) with excellent reproducibility (2.96–––5.18 %), high selectivity and stability for duration of up to 4 months, assuring easy, fast and real-time non-invasive monitoring of ascorbic acid. The findings are analyzed using theories and basic research.