Synthesis and Characterization of Core-Shell Ag:Au Nanoparticles via Seed Growth for Gas Sensor Applications

Ag:Au nanoparticles are prepared and studied in the form of pure, stable, highly concentrated, and non-toxic core-shell; the method of preparation was the seed growth method which involves preparation of silver seeds and is done via a chemical reaction between AgNO3, Na3C6H5O7, and NaBH4 to produce them; the next step was done by another chemical reduction of C(6)H(8)O(6 )and HAuC(14 )in a CTAB solution in different quantities (0.4 ml, 0.6 ml, 0.8 ml, and 1 ml). The morphology study revealed that the Ag:Au (core-shell) NPs deposited on porous silicon (PS) exhibited strong adhesion, leading improved structural stability of the PS substrate. Analysis of the UV-Vis spectra of NPs showed a localized surface plasmon resonance (LSPR) band within the spectral range of (420 to 540) nm wavelength. As the amount of gold Au NPs increased, the LSPR band transitioned from two peaks to almost one. In this work, the Ag:Au (core-shell) NPs are manufactured by seed growth method these nanoparticles are deposited on porous silicon (PS). Photoluminescence spectra, X-ray, TEM, UV-vis, and Raman were found. This research will provide some guidance to the developers of the n-type based Ag:Au (core-shell) NPs/PS sensor.