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Tin‐based nanowire electrodes present desirable properties as lithium‐ion battery anodes, because they undergo volume changes without pulverization. However, they suffer from limited mass loading and propensity for surface parasitic reactions. Herein, the electrochemical performances of nickel–tin 3D‐interconnected nanowire network (NiSn 3DNWN) electrodes are evaluated with the nanowire diameters of 40, 105, and 230 nm, respectively, that attain mass loadings of up to 3 mg cm−2. To mitigate the surface parasitic reactions, the effects of fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives are investigated as a function of the nanowire diameter and additive concentration. The results show that the FEC and VC of all compositions improve the capacity retentions and coulombic efficiencies (CEs) of the NiSn 3DNWN electrodes. In 10 vol% FEC, the electrodes demonstrate a similar capacity of ≈550 mAh g−1, but the capacity retentions after 100 cycles are 73.68%, 53.79%, and 51.70% for the 40, 105, and 230 nm NiSn 3DNWN, respectively. However, the 105 nm‐diameter nanowire electrode has the highest average CE of 96.55%. Electrochemical impedance spectroscopy and post‐cycling investigations reveal that the FEC has the most profound effect on the interfacial resistances, which is reflected in the rate performances of the tested electrodes. [ABSTRACT FROM AUTHOR]

The difficulty to generate and control large strain gradients in materials hinders the investigation and application of flexoelectricity and flexomagnetism. This work demonstrates that thermal expansion can be used to induce very large non‐uniform strains at the nanoscale, resulting in giant strain gradients at moderate temperatures. This is demonstrated in a nanopatterned multiferroic hybrid layer consisting of a regular array of ferromagnetic metallic nanocylinders embedded in a ferroelectric polymer matrix. The thermally‐induced strain gradients can fully depolarize the ferroelectric component, and modify the magnetization of the ferromagnetic component via flexoelectric and flexomagnetic effects, respectively. Finite‐element analysis provides a quantitative view on thermal expansion‐induced strains and strain gradients supporting the experimental findings. This work shows that nanoscale thermal strain engineering provides an additional degree of freedom to control electrical polarization and magnetization, which paves the way for the design and operation of novel functional devices and nanostructures. [ABSTRACT FROM AUTHOR]