Facile general strategy toward hierarchical mesoporous transition metal oxides arrays on three-dimensional macroporous foam with superior lithium storage properties

Abstract

Nanostructured transition metal oxides (NTMOs) with hierarchically porous structures grown on conductive substrates have been considered as promising electrode materials for lithium-ion batteries (LIBs). However, a grand challenge still exists in developing facile and generalized approaches for rational design and fabrication of them in large scale. Here we first present a facile general strategy, namely, chemical bath deposition followed by calcination, for the scalable synthesis of diverse NTMOs arrays with hierarchically porous structures and their corresponding hybrid nanowire arrays that are directly grown on conductive substrates. When directly used as binder- and conductive-agent-free anodes for LIBs, the resultant nanoarchitectured electrodes manifest outstanding electrochemical performances with high specific capacity, superior rate capability and excellent cycling stability. Specifically, a high reversible capacity of 1145 mA h g(-1) is retained after 100 cycles at 100 mA g(-1), and a reversible capacity up to 639 mA h g(-1) even after 500 cycles at a current density as high as 1000 mA g(-1) can be maintained by using hierarchically porous flower-like Zneo(2)O(4) nanosheets as anode material, holding great promise as efficient electrodes for LIBs. This facile general strategy could represent a milestone in the design and synthesis of various hierarchical mesoporous selfsupported NTMOs arrays and hybrid hierarchical nanocomposites that are promising for a wide range of applications such as electrochemical energy storage, catalysis, gas sensors and other fields.