Acoustic shock wave engineering of cadmium selenide: Structural, optical, and morphological evolution

Abstract

This study examines the effects of acoustic shock waves on the structural, optical and, morphological properties of cadmium selenide (CdSe) nanoparticles, aiming to enhance their application in solar cells and energy conversion applications. CdSe is noted for its excellent light absorption; however, its inherently weak structure under extreme conditions limits its long-term stability and solar cell performance. To observe changes in its structure, optical and morphological properties and to check its stability under extreme conditions, CdSe is subjected to acoustic shock waves at a pressure of 0.59 MPa, a temperature of 520 K, and a Mach number of 1.5. Analytical techniques are employed, including X-ray diffraction (XRD), Raman spectroscopy, UV–Vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL), and high-resolution scanning electron microscopy (HR-SEM). Results show significant improvements, such as lower strain rates and enhanced crystallinity. The crystallite size increased from 2.8 to 3.3 nm. The bandgap shifts from 1.761 eV to 1.741 eV, and enhanced PL intensity indicates improved light absorption, and a more uniform and clearer needle-like morphology under shock-loaded conditions, which may lead to better mechanical properties. The overall study finds that CdSe structural robustness, improved optical properties, and reduced defects, such as lattice strain and distortion, effectively reduce the material's degradation issue. The optical and morphological properties were tuned to improve the solar cell performance. These findings highlight the novelty of using acoustic shock wave treatment as a quite new technique to uniquely enhance the structural, optical, and morphological properties of CdSe. Such comprehensive improvements make it a promising approach for increasing both the efficiency and durability of CdSe-based solar and energy conversion devices.