Calcium Vanadate Micro/Nanostructures for Lithium-Ion Batteries

Abstract

The ability to control the composition and structure of inorganic compounds by simple synthesis methods is essential to the design and development of electrode materials of lithium-ion batteries (LIBs). Here we report the controllable synthesis of calcium vanadate micro/nanostructures via a simple hydrothermal method. By easily adjusting the pH value of a reaction system, a Ca10V6O25 straw-bundle-like structure, Ca2V2O7 microplatelet, and CaV6O16·3H2O sponge-like macrostructure can be selectively synthesized. The regulation mechanism of different calcium vanadate micro/nanostructures was investigated. In addition, CaV6O16·3H2O and CaV6O16·3H2O/GO self-standing papers were obtained by pressing the sponge-like macrostructure and vacuum filtration, respectively. The electrochemical performances of the CaV6O16·3H2O and CaV6O16·3H2O/GO papers as the self-standing and binder-free anodes for LIBs were investigated for the first time. The as-obtained CaV6O16·3H2O/GO hybrid paper anode exhibits a high discharge capacity of 664.0 mA h g–1 after 250 cycles at 200 mA g–1 and good cycling stability, demonstrating its potential application as a self-standing anode for LIBs.

High-Capacity Calcium Vanadate Composite with Long-Term Cyclability as a Cathode Material for Aqueous Zinc-Ion Batteries

“…The peak intensities of Zn 2p were significantly reduced after full charge (1.6 V), revealing the de-insertion of Zn 2+ . The high-resolution core-level Ca 2p spectrum is shown in Figure S4c of the Supporting Information, and the peaks appeared at 345 eV (2p 3/2 ) and 350.7­(2p 1/2 ) eV in their pristine state, which indicates the presence of Ca 2+ . No Ca 2p signals were observed in the charge and discharge states.…”

“…The high-resolution core-level Ca 2p spectrum is shown in Figure S4c of the Supporting Information, and the peaks appeared at 345 eV (2p 3/2 ) and 350.7(2p 1/2 ) eV in their pristine state, which indicates the presence of Ca 2+ . 78 No Ca 2p signals were observed in the charge and discharge states. This means that Ca ions do not participate in the electrochemical reactions, but they can serve as pillars.…”

Highly Selective and Reversible Detection of Simulated Breath Hydrogen Sulfide Using Fe‐Doped CuO Hollow Spheres: Enhanced Surface Redox Reaction by Multi‐Valent Catalysts

“…The response, selectivity, recovery status, and humidity levels of CuObased gas sensors to H 2 S reported in the literature are summarized (Table 1). [49][50][51][52][53][54][55][56][57][58][59] Note that, the selectivity to 0.1 ppm H 2 S in this work was compared with 0.5-5 ppm of ethanol, acetone, hydrogen, or CO, respectively. Considering H 2 S high selectivity and recovery kinetics, 4Fe-CuO sensor exhibited prominent performance to quantify the H 2 S concentration in a high-humidity atmosphere (RH = 80%).…”

Kinetically controlled synthesis of low-strain disordered micro–nano high voltage spinel cathodes with exposed {111} facets

“…Meanwhile, designing micro-nano hierarchical structure materials can preserve the characteristics of nanostructures and combine the advantages of micrometer structures. [29][30][31][32] Besides, the crystal facets of the LNMO also affect its electrochemical performance. Previous studies have shown that choosing crystal facets with lower surface energy can help stabilize the crystal structure and reduce the occurrence of interfacial side reactions.…”