Laser-Assisted Synthesis of Mg-MgO-Mg₁₇Al₁₂ Nanoparticles on Porous Silicon for Enhanced Photodetector Performance

Abstract

This study examines the synthesis, characterization, and optoelectronic properties of Mg-MgO-Mg₁₇Al₁₂ nanoparticles (NPs) created through laser ablation in ethanol. While significant efforts have been devoted to binary MgO materials, integrating ternary Mg-based nanoparticles with porous silicon remains a promising avenue for enhancing the broad-spectrum response of Si-based photodetectors. Consequently, this work addresses the challenge of limited spectral response by engineering a ternary Mg-MgO-Mg₁₇Al₁₂/PS hybrid layer. The NPs were produced using a Nd: YAG laser (1064 nm, 10 ns, 1 Hz) and were drop-cast onto photoelectrochemically etched porous silicon (PS) substrates. UV–Vis, SEM, and XRD analyses showed that the tetragonal metallic crystal phase was achieved with particle sizes ranging from 4.8 to 10.7 nm. The band gap increased with varying size, while the spectral responsivity reached 0.31 A/W (EQE ≈ 86%) at 450 nm. These findings show that Mg-MgO-Mg₁₇Al₁₂ NPs on PS significantly enhance broadband photodetector performance and provide an effective pathway for future practical applications in optoelectronic and related device technologies.