Reversible Size Control of Liquid‐Metal Nanoparticles under Ultrasonication

Abstract

This paper describes the reversible control of the size of liquid-metal nanoparticles under ultrasonication. Gallium was utilized as a liquid metal, which has a melting point of 29.8 °C. Investigating the effects of ultrasonication (power, time, and temperature) on the formation of gallium nanoparticles revealed that the process is similar to the formation of oil in water (O/W) or water in oil (W/O) emulsions, as the temperature significantly affects the size of the gallium nanoparticles (GaNPs). Under ultrasonication, the balance between the break-up and coalescence of the GaNPs can be adjusted by changing the temperature or adding acid through modulating the natural surface oxide layer (which can be removed with acid) and the stabilizing effect of the surfactant dodecanethiol. Coalescence was predominant at higher temperatures, whereas particle break-up was found to be predominant at lower temperatures. Furthermore, the change in size was accompanied by a shift in the plasmonic absorption of the GaNPs in the UV region.

Light-driven liquid metal nanotransformers for biomedical theranostics

“…LMs such as gallium, gallium-indium eutectic alloys (EGaIn: 75% Ga, 25% In (wt wt −1 )), and gallium-indium-tin alloys (Galinstan: 68.5% Ga, 21.5% In and 10% Sn (wt wt −1 )), with melting points of 29.8, 15.7 and 10.7 °C, respectively, have received increasing attention because they are generally chemically stable and do not react with water at room temperature. In addition, previous studies have shown that such alloys are safe for humans under normal circumstances345678910. Currently, there is a significant interest towards the chemical345 and morphological characterization of these emerging LMs56789.…”

“…In addition, previous studies have shown that such alloys are safe for humans under normal circumstances345678910. Currently, there is a significant interest towards the chemical345 and morphological characterization of these emerging LMs56789. Furthermore, as opposed to mercury and solid metals such as gold or silver nanoparticles whose optical properties have been extensively investigated, those of promising LMs have not been sufficiently explored11121314.…”

“…Furthermore, as opposed to mercury and solid metals such as gold or silver nanoparticles whose optical properties have been extensively investigated, those of promising LMs have not been sufficiently explored11121314. Current major challenges are the simple production of LM spherical droplets and chemical functionalization of LM nanoconjugates41015. They require not only exquisite synthesis strategies but also unravelling the mystery of the unique properties in LMs.…”

Pengendalian Suhu Ultrasonikasi Pada Pelapisan Nanopartikel Magnet (Fe3O4) Dengan Kitosan

“…Proses ultrasonikasi memang merupakan teknik unggul dalam menghasilkan partikel berukuran nanometer (Yamaguchi, Mashima, dan Iyoda 2015). Namun demikian dalam proses ini akan terbentuk panas tinggi yang dapat mempengaruhi karakteristik bahan yang diproses.…”

“…Tahap selanjutnya adalah peningkatan ukuran gelembung akibat proses difusi larutan kedalam gelembung dan dilanjutkan dengan tahap ketiga pecahnya gelembung saat ukurannya telah mencapai maksimal. Pecahnya gelembung ini dapat meningkatkan suhu sekitar gelembung hingga 5000 K (4727 °C) dan tekanan hingga ratusan atmosfer (Yamaguchi, Mashima, dan Iyoda 2015). Kondisi ekstrim ini dapat menyebabkan putusnya ikatan kimia bahanbahan yang ada di sekitar gelembung.…”