Laser Irradiation of Gd-Si and Gd-Si-Ge Colloid Mixtures for the Fabrication of Compound Nanoparticles

Binary (Gd5Si4, GdSi) and ternary (Gd5Si2Ge2) compound nanoparticles (NPs) were prepared by laser irradiation of a mixture of colloidal solutions containing NPs of the relevant elements. It is assumed that the compound NPs are formed by heating, co-melting, and chemical interactions in the alloyed droplets. The blackbody-like radiation of the heated NPs was used for temperature control of the NP-preparation process. The obtained results demonstrate that laser irradiation of colloidal NPs provides unique possibilities not only for the synthesis of compound NPs but also for control of their phase composition and size. The synthesized Gd-based compound NPs exhibited magnetic transition at an ordering temperature, T-C, in the range of 310-320 K. Thus, the magnetic properties of the synthesized particles confirm their potential for biomedical applications, in particular, for magnetic hyperthermia treatment.