Bimetallic nanoparticles anchored CVD grown SnS₂ flakes based Chemiresistive Ascorbic Acid Sensor

Ascorbic acid (AA) is crucial in metabolic activities, serving as a scavenger to avert oxidative damage. Consequently, there is an imperative requirement for a highly sensitive, selective, and cost-effective sensing platform for the detection of AA. We introduced a useful method for detecting AA using SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> anchored with gold-silver (Au-Ag) nanoparticles (NPs). These bimetallic nanoparticles usually have better catalytic abilities than single-metal ones. Here we grow SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> flakes utilizing a simple - chemical vapor deposition (CVD) method to address the growing demand for a reliable detecting platform. To optimize device properties, we deposited Au/Cr contacts using shadow mask on the SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> flakes and subsequently passivated them with Si3N4 to avert electrical shorting. The sensors resistance was measured in the absence and presence of AA, while selectivity was analysed for various biomolecules, revealing a high selectivity for AA. The Au-Ag-SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>-based device exhibited a response of 129.7% to 1 mM of AA biomolecules, surpassing all other devices and demonstrating almost double increase in sensing response compared to the pristine SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> device. The outcomes of this work illustrate the effectiveness of Au and Ag NPs anchored SnS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> as a desirable material for AA detection. This discovery advances our ability to monitor and identify AA, promoting progress in biomedical, industrial, and environmental applications.