Solution processable liquid metal nanodroplets by surface-initiated atom transfer radical polymerization

152

120

Liquid metals are emerging as fluidic inorganic materials in various research fields. Micro‐ and nanoparticles of Ga and its alloys have received particular attention in the last decade due to their non toxicity and accessibility in ambient conditions as well as their interesting chemical, physical, mechanical, and electrical properties. Unique features such as a fluidic nature and self‐passivating oxide skin make Ga‐based liquid metal particles (LMPs) distinguishable from conventional inorganic particles in the context of synthesis and applications. Here, recent advances in the bottom‐up and top‐down synthetic methods of Ga‐based LMPs, their physicochemical properties, and their applications are summarized. Finally, the current status of the LMPs is highlighted and perspectives on future directions are also provided.

Section: Discussionmentioning

confidence: 99%

Section: Properties Of Micro/nano‐sized Liquid Metalmentioning

confidence: 99%

Ga‐Based Liquid Metal Micro/Nanoparticles: Recent Advances and Applications

Song

Kim

Kang

et al. 2019

152

120

“…Most of the fabrication procedures of LM micro/nanodroplets mixtures are similar to the formation of oil in water (O/W) or water in oil (W/O) emulsion . Microscale LMs droplets can be efficiently fabricated with uniform size distribution and spherical shape by microfluidic approaches in aqueous solution.…”

Section: Liquid Metal: Category and Naturementioning

confidence: 99%

Liquid Metal–Based Soft Microfluidics

Zhu

Wang

Handschuh‐Wang

et al. 2019

160

123

Motivated by the increasing demand of wearable and soft electronics, liquid metal (LM)‐based microfluidics has been subjected to tremendous development in the past decade, especially in electronics, robotics, and related fields, due to the unique advantages of LMs that combines the conductivity and deformability all‐in‐one. LMs can be integrated as the core component into microfluidic systems in the form of either droplets/marbles or composites embedded by polymer materials with isotropic and anisotropic distribution. The LM microfluidic systems are found to have broad applications in deformable antennas, soft diodes, biomedical sensing chips, transient circuits, mechanically adaptive materials, etc. Herein, the recent progress in the development of LM‐based microfluidics and their potential applications are summarized. The current challenges toward industrial applications and future research orientation of this field are also summarized and discussed.

“…It has been suggested that mixing rubbery polymers with micro and nanoparticles of gallium alloys can be potentially used as flexible conductors in the form of slurry inks . The liquid metal micro or nanodroplets can be directly obtained from their respective bulks using easily accessible techniques such as sonication and surface modification . Advantageously, in comparison to their conventional solid (rigid) counterparts, liquid metal fillers themselves are highly deformable .…”

Section: Introductionmentioning

confidence: 99%

Liquid Metal Droplet and Graphene Co‐Fillers for Electrically Conductive Flexible Composites

Saborío

Cai

Tang

et al. 2019

107

126

Colloidal liquid metal alloys of gallium, with melting points below room temperature, are potential candidates for creating electrically conductive and flexible composites. However, inclusion of liquid metal micro‐ and nanodroplets into soft polymeric matrices requires a harsh auxiliary mechanical pressing to rupture the droplets to establish continuous pathways for high electrical conductivity. However, such a destructive strategy reduces the integrity of the composites. Here, this problem is solved by incorporating small loading of nonfunctionalized graphene flakes into the composites. The flakes introduce cavities that are filled with liquid metal after only relatively mild press‐rolling (<0.1 MPa) to form electrically conductive continuous pathways within the polymeric matrix, while maintaining the integrity and flexibility of the composites. The composites are characterized to show that even very low graphene loadings (≈0.6 wt%) can achieve high electrical conductivity. The electrical conductance remains nearly constant, with changes less than 0.5%, even under a relatively high applied pressure of >30 kPa. The composites are used for forming flexible electrically‐conductive tracks in electronic circuits with a self‐healing property. The demonstrated application of co‐fillers, together with liquid metal droplets, can be used for establishing electrically‐conductive printable‐composite tracks for future large‐area flexible electronics.