Electrical, thermal, and species transport properties of liquid eutectic Ga-In and Ga-In-Sn from first principles

Abstract

Using ab initio molecular dynamics, the atomic structure and transport properties of eutectic Ga-In and Ga-In-Sn are investigated. The Kubo-Greenwood (K-G) and the Ziman-Faber (Z-F) formulations and the Wiedemann-Franz (W-F) law are used for the electrical and electronic thermal conductivity. The species diffusivity and the viscosity are also predicted using the mean square displacement and the Stokes-Einstein (S-E) relation. Alloying Ga causes more disordered structure, i.e., broadening the atomic distance near the In and Sn atoms, which reduces the transport properties and the melting temperature. The K-G treatment shows excellent agreement with the experimental results while Z-F treatment formula slightly overestimates the electrical conductivity. The predicted thermal conductivity also shows good agreement with the experiments. The species diffusivity and the viscosity are slightly reduced by the alloying of Ga with In and Sn atoms. Good agreements are found with available experimental results and new predicted transport-property results are provided.

High thermal conductivity in soft elastomers with elongated liquid metal inclusions

“…Compared with previous attempts with LM-filled elastomers (12), we have discovered that strain creates thermally conductive pathways through the in situ elongation of the deformable liquid inclusions, which significantly enhances thermal conductivity in the stretching direction. For permanent (stressfree) and strain-controlled elongation of the LM inclusions, this enhanced k is nearly 25× to 50× greater than the unfilled elastomer (0.20 ± 0.01 W·m ) and approaches the limit for the parallel rule of mixtures of an EGaIn−silicone composition (23) without the aid of percolating networks. Referring to Fig.…”

Materials and Structures toward Soft Electronics

“…Therefore, there is a tradeoff between the thermal conductivity and elastic modulus. This dilemma can be overcome by using the liquid metals for thermal transport thanks to their high thermal conductivity (26.4 W m −1 K −1 at 30 °C) and liquidity . Elastomers embedded with liquid metals that function as thermoconductive highways have been reported .…”

Temperature-dependent structure evolution in liquid gallium

“…Recently, it was also revealed in pure liquid Ce [20], supercooled liquid Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 [23] and liquid La 50 Al 35 Ni 15 [47], remaining as an intriguing but still elusive phenomenon in metallic liquids. For several monoatomic metallic liquids (i.e., Al, Zn, Sn and In), Lou et al [21] found that the interatomic distances between the center atom and those on the first shell contract with increasing temperature, which promotes deeper understanding on the atomic structure evolution in metallic liquids [22,[24][25][26][27]29,[31][32][33][34][36][37][38]51]. The wide liquid region of gallium (Ga) with a low melting temperature (303 K) and extremely high boiling point (2477 K) at atmospheric pressure could facilitate a detailed study of its temperature-dependent liquid structure.…”