Detection of dangerous metallic oxides nano-powders by a one-dimensional resonant phononic crystal sensor

Abstract

Healthy water is a requisite requirement for human life. In the current investigation, we introduced theoretically an ultra-sensitive resonant phononic crystal structure as a chemical and fluidic sensor, which is considered to specify the type of some dangerous metallic oxides. The proposed design is a solid/solid crystal with a central defect filled with an aqueous solution from the targeted oxide solutions. These oxides include nanoparticles such as NiO, ZnO, Fe3O4, Fe2O3, and Al2O2, which can cause toxicity in the freshwater. As a primary step, the optimization process implements the type of structure, the thickness of each layer, the number of unit cells, and the incident angle. Each metallic oxide possesses specific acoustic properties and specific resonance peak consequently. The performance of the designed sensor is investigated by selecting Al2O2 as a reference solution and considering the optimum condition of the design geometry. The highest sensitivity is related to Fe2O3, with the value of 5.61 × 104 m−1 and the highest Q-factor is obtained for ZnO with the value of 1.57 × 103. In addition, the best figure of merit (FOM) is obtained for NiO solution with the value of 10.01 × 107 s/m. Given the current situation, the proposed sensor structure can provide a wide range of applications for various fluids and environmental pollutions.