Investigating how wave propagation affects the functionality of surface acoustics wave (SAW) macro- and nanosensors is the main objective of the current investigation. Consequently, the surface piezoelectricity theory is used to investigate shear horizontal waves (SH) in an orthotropic PQC layer that is layered on top of an elastic framework (Model I), a piezoelectric substrate, and an orthotropic PQC substrate (Model II). Approach: A variable-separable approach is used in the study. Based on the differential equations and matrix formulation, theoretical forms are created and utilized to display the wavenumber of surface waves in any direction of the piezoelectric medium. Two configurations are examined: an orthotropic piezoelectric material layer over an elastic framework and a piezoelectric material half-space with a nanosubstrate. Analytical expressions for frequency equations are derived for both symmetric and anti-symmetric waves. Study investigates the effects of surface elastic constants, surface density, anisotropic piezoelectric constant, and symmetric and anti-ssymmetric modes on phase velocity. The study is confined to only linear wave propagation. Additionally, the analysis is based on idealized material properties and surface properties of the material. Surface effect study is the novelty which is conducted in the piezoelectric model and their applications in sensors. The findings of this research may be useful in designing surface acoustic wave sensors (SAW) devices.
