posted on 2019-08-13, 13:04authored byHaomiao Li, Kangli Wang, Min Zhou, Wei Li, Hongwei Tao, Ruxing Wang, Shijie Cheng, Kai Jiang
Nanoengineering of
metal electrodes are of great importance for
improving the energy density of alkali-ion batteries, which have been
deemed one of most effective tools for addressing the poor cycle stability
of metallic anodes. However, the practical application of nanostructured
electrodes in batteries is still challenged by a lack of efficient,
low-cost, and scalable preparation methods. Herein, we propose a facile
chemical dealloying approach to the tunable preparation of multidimensional
Sb nanostructures. Depending on dealloying reaction kinetics regulated
by different solvents, zero-dimensional Sb nanoparticles (Sb-NP),
two-dimensional Sb nanosheets (Sb-NS), and three-dimensional nanoporous
Sb are controllably prepared via etching Li–Sb alloys in H2O, H2O-EtOH, and EtOH, respectively. Morphological
evolution mechanisms of the various Sb nanostructures are analyzed
by scanning electron microscopy, transmission electron microscopy,
and X-ray diffraction measurements. When applied as anodes for sodium
ion batteries (SIBs), the as-prepared Sb-NS electrodes without any
chemical modifications exhibit high reversible capacity of 620 mAh
g–1 and retain 90.2% of capacity after 100 cycles
at 100 mA g–1. The excellent Na+ storage
performance observed is attributable to the two-dimensional nanostructure,
which ensures high degrees of Na+ accessibility, robust
structural integrity, and rapid electrode transport. This facile and
tunable approach can broaden ways of developing high performance metal
electrodes with designed nanostructures for electrochemical energy
storage and conversion applications.