Self-Assembly Growth of 3D WO₃Framework with Interpenetrated Nanosheets as Binder-Free Anode for Lithium Ion Batteries

Abstract

A novel three-dimensional (3D) tungsten trioxide (WO3) framework is self-assembly grown from tungsten (W) foil by an anodization process. The as-prepared framework is constructed by interpenetrated WO3 nanosheets with the thickness of 30 nm, which exhibits a larger specific area and can be directly used as binder-free anode for lithium ion battery. This unique structure could benefit to relieve the stress caused by the volume change during the electrochemical reaction. Besides, the direct contact between the WO3 nanosheets and the metallic substrate could also contribute to the better adhesion and higher electronic conductivity. Furthermore, electronic conductive silver (Ag) nanoparticles (NPs) are anchored uniformly on the WO3 nanosheets, which greatly enhance the electronic conductivity of 3D WO3 framework and the stability of ‘solid-electrolyte interphase’ (SEI) film. With the optimal decorated amount of Ag NPs, the electrode not only delivers the highest capacity of 681 mAh g−1 after 150 cycles, but also manifests an excellent reversible capacity as high as 370 mAh g−1 at a high rate of 1 mA cm−2.

The Use of Anodic Oxides in Practical and Sustainable Devices for Energy Conversion and Storage

“…Annealing for oxide crystallization was performed at 400–500 °C for 2–3 h [ 20 , 21 ]. On the other hand, the fabrication of nanosheets arrays of WO 3 for LIB applications was performed via a two-anodization method in an H 2 SO 4 solution [ 72 ]. Each potentiostatic anodization was carried at 15 V for 2 h and 24 h. The WO 3 layer formed in the first step was removed by ultrasonication in water.…”

“…Regarding other anodized oxides, some studies described the use of nanostructured WO 3 and Sn@Cu x O in LIBs [ 72 , 79 ], SnO x , and Nb 2 O 5 in SIBs [ 148 , 149 , 151 ], and ZnO in ZIBs [ 76 ]. Due to its high theoretical capacity (696 mA·h·g −1 ) [ 72 ], WO 3 is also a potential material for anodes in LIBs. The drawback of its application is the aggregation of the WO 3 nanomaterials, which reduces its capacity.…”

“…The drawback of its application is the aggregation of the WO 3 nanomaterials, which reduces its capacity. To minimize this effect, Yang et al [ 72 ] produced a 3D network of WO 3 nanosheet arrangements via two-step anodization of W foil and decorated it with Ag-NPs to enhance electronic conductivity. The Ag-NP was loaded into the WO 3 layer via sol-gel and spin-coating techniques.…”

“…The drawback of its application is the aggregation of the WO3 nanomaterials, which reduces its capacity. To minimize this effect, Yang et al [72] produced a 3D network of WO3 nanosheet arrangements via two-step anodization of W foil and As an alternative to LIBs, SIBs are receiving much attention in modern studies, since these batteries are based on sustainable precursors and more secure raw material supplies [151,152]. However, despite the similar chemistry of lithium and sodium, the large radius of the sodium ion compromises its reversible intercalation into the conventional graphite anodes.…”