3D hierarchical porous sponge-like V(2)O(5 )micro/nano-structures for high-performance Li-ion batteries

As cathode materials for Li-ion batteries (LIBs), V2O5, possessing a large-spaced and open layered crystal structure, have attracted considerable attention due to their distinct advantages of high specific capacity, abundant raw materials and low cost. Although low-dimensional nanostructured V2O5 can increase the discharge capacity of LIBs, it still suffers from poor cycling and rate performance due to serious self-aggregation and pulverization. Building micro/nano-structures is a highly promising method to address the above issues. Herein, we propose a facile oxidation strategy to successfully synthesize the unique 3D hierarchical porous sponge-like V2O5 micro/nano-structures (V2O5-SLMNSs) by using the structure-similar sponge-like VO2 (B)@C micro/nano-structures as a precursor. Importantly, assynthesized V2O5-SLMNSs possess the distinct structural advantages of a robust structure with large surface area and abundant meso/micropores, which are beneficial for achieving a better electrochemical performance. Specific capacity during the second discharge for V2O5-SLMNSs is 232 mAh/g at 100 mA/g, with 87% of the capacity being maintained after 50 cycles, which is considerably higher than the discharge capacity (190 mAh/g) in the second cycle and the value for the capacity retention (69%) of 1D V2O5 nanoribbons. Thus, as-synthesized V2O5-SLMNSs are promising cathode materials for the next-generation LIBs. (C) 2018 Elsevier B.V. All rights reserved.