Rationally designed electrode materials with high capacity, long cycle life, and low cost are indispensable for sodium‐ion batteries. Herein, a hierarchical nanobox consisting of a heterojunction bimetallic selenide yolk and polydopamine shell (denoted as SnSe2/ZnSe@PDA) is engineered and fabricated successfully. Owing to the charge redistribution and lattice distortion at the hetero‐phase boundaries, Na+ ions can be easily adsorbed and transferred swiftly, facilitating the reaction kinetics and promoting cycling behavior. By means of the hollow structure and elastic polymer shell, this approach can synergistically alleviate volume fluctuation and the aggregation of active nanomaterials during cycling. This material delivers a high reversible capacity of 616 mA h g‐1 at 1 A g‐1 over 1000 long‐term cycles, and superior rate capability, which provides more possibilities for the practical applications of energy storage in the future.

To elucidate the mechanism underlying the effect of polymer/solid interfacial interactions on the dynamics of thin polymer films, the glass transition of thin end-functionalized polystyrene films supported on SiO-Si, such as proton-terminated PS (PS-H), α,ω-dicarboxy-terminated PS (PS-COOH), and α,ω-dihydroxyl-terminated PS (PS-OH), was investigated. All the PS films exhibited a substantial depression in T with decreasing film thickness, while the extent of such depression was strongly dependent on the chemical structure of the end groups and molecular weights. It was found that T - T of the various PS films increased linearly with increasing h/R, in which h is the thickness of the interfacial adsorbed layer and R is the radius of gyration of PS. The h/R is a direct reflection of the macromolecular chain conformation within the adsorbed layer which was affected by its end groups and molecular weights. These findings are in line with the work of Napolitano, and present direct experimental evidence.

N-doped CoSb@C nanofibers as self-supporting anode improved K-ion and Na-ion storage.