Ab initio molecular dynamics study on the disordered Li-Ga-Sn system.

The eutectic Ga91.6Sn8.4 liquid metal could serve as the anode in Li-ion batteries to avoid dendrite growth issue and volume expansion, and maintain a good cycle life. However, the microstructure and the basic physical properties of the lithiated Ga91.6Sn8.4 are ignored in experiments and still unclear. In this work, we assume that a disordered structure is formed in the initial stage of lithiation of Ga91.6Sn8.4, and the structure, equilibrium density, thermal expansion coefficient, mixing enthalpy, self-diffusion coefficient and viscosity of the disordered Li-Ga-Sn system are investigated systematically by ab initio molecular dynamics. The radial distribution function, structure factor and bond angle distribution function are calculated to obtain local structure information. Our calculations show that the lithiation of Ga91.6Sn8.4 is exothermic, and for most cases, the diffusion coefficients for Li, Ga and Sn decrease with increasing Li content. Based on structural information and diffusion coefficients, we reveal that the lithiation of Ga91.6Sn8.4 will make the liquid Ga91.6Sn8.4 alloy form a solid-like structure. With the increase of Li content, it is more likely to form a solid-like structure. Furthermore, our simulations reveal that the chemical interaction of Li-Sn and Li-Ga is stronger than that of Ga-Sn, and Li is prone to combine with Sn firstly in the lithiation process of Ga91.6Sn8.4.

Magnetostrictive-Piezoelectric-Triggered Nanocatalytic Tumor Therapy.

Magnetic-based theranostics feature a high efficiency, excellent tissue penetration, and minimal damage to normal tissues, are noninvasive, and are widely used in the diagnosis and therapy of clinical diseases. Herein, a conceptually novel magnetostrictive-piezoelectric nanocatalytic medicine (MPE-NCM) for tumor therapy is proposed by initiating an intratumoral magneto-driven and piezoelectric-catalyzed reaction using core-shell structured CoFe2O4-BiFeO3 magnetostrictive-piezoelectric nanoparticles (CFO-BFO NPs) under an alternating magnetic field. The CFO-BFO NPs catalyze the generation of cytotoxic reactive oxygen species (ROS): superoxide radicals (•O2-) and hydroxyl radicals (•OH). The simulation calculation demonstrates the highly controllable electric polarization, facilitating the above catalytic reactions under the magnetic stimulation. Both a detailed cell-level assessment and the tumor xenograft evaluation evidence the significant tumor eradication efficacy of MPE-NCM. This study proposes an original and novel magneto-responsive nanocatalytic modality for cancer therapy, which displays promising prospects for the future clinic translation owing to its excellent catalytic dynamic responsiveness, high therapeutic efficacy, and biosafety in vivo.