Novel insight toward engineering of arrayed Cu@Sn nanoelectrodes: Rational microstructure refinement and its remarkable "harvesting effect" on lithium storage capability

The impact of morphological and compositional evolutions of arrayed Cu@Sn nanoelectrodes on their lithium storage capability is investigated in this work. Strikingly, it is found that the diameter of Cu nanowire-core, inter-wire spacing, as well as Sn/Cu ratio of such nanohybrids could be directly adjusted through a synchronous electrochemical dissolution/deposition strategy in a single bath. In line with expectation, nanoarchitecture tailoring of the array-type electrode brings in expanded space available and enhanced interfacial adhesion, which can not only effectively enable high loading of conformal Sn nanolayers on per unit footprint area but also help in suppressing capacity fading, and thus harvesting outstanding areal capacity (∼1.46 mAh cm^-2 at 0.2 mA cm^-2) and rate capability. It is envisioned that such work will shed light on ways to facilely tune the characteristic parameters of a series of Cu-cored hybrid nanowire arrays with desired functionalities for nanodevice applications.