The rapidly expanding field of nonaqueous multivalent intercalation batteries offers a promising way to overcome safety, cost, and energy density limitations of state-of-the-art Li-ion battery technology. We present a critical and rigorous analysis of the increasing volume of multivalent battery research, focusing on a wide range of intercalation cathode materials and the mechanisms of multivalent ion insertion and migration within those frameworks. The present analysis covers a wide variety of material chemistries, including chalcogenides, oxides, and polyanions, highlighting merits and challenges of each class of materials as multivalent cathodes. The review underscores the overlap of experiments and theory, ranging from charting the design metrics useful for developing the next generation of MV-cathodes to targeted in-depth studies rationalizing complex experimental results. On the basis of our critical review of the literature, we provide suggestions for future multivalent cathode studies, including a...

Odyssey of Multivalent Cathode Materials: Open Questions and Future Challenges

Aqueous zinc ion batteries (ZIBs) are truly promising contenders for the future large-scale electrical energy storage applications due to their cost-effectiveness, environmental friendliness, intri...

Active Materials for Aqueous Zinc Ion Batteries: Synthesis, Crystal Structure, Morphology, and Electrochemistry

Recent advances in aerogels for environmental remediation applications: A review

Low-density nanoscale mesoporous composites may be readily synthesized by adding a colloidal or dispersed solid to an about-to-gel silica sol. The silica sol can "glue" a range of chemically and physically diverse particles into the three-dimensional silica network formed upon gelation. If the composite gel is supercritically dried so as to maintain the high porosity of the wet gel, a composite aerogel is formed in which the nanoscopic surface and bulk properties of each component are retained in the solid composite. The volume fraction of the second solid can be varied above or below a percolation threshold to tune the transport properties of the composite aerogel and thereby design nanoscale materials for chemical, electronic, and optical applications.

https://science.sciencemag.org/content/sci/284/5414/622.full.pdf

Silica Sol as a Nanoglue: Flexible Synthesis of Composite Aerogels

Microwave-assisted synthesis of metal oxide/hydroxide composite electrodes for high power supercapacitors – A review

Alumina aerogels were prepared by a sol–gel method combined with the ethanol supercritical drying technique using aluminum tri-sec butoxide and nitric acid as the precursor and catalyzer respectively. This method affords high-surface-area alumina aerogel monoliths without the use of complexing agents. The structure and morphology of the aerogels were investigated by TEM, XRD, FTIR and BET techniques. The results confirmed that the as-prepared alumina aerogel possessed a network microstructure made up of pseudoboehmite fibers and a surface area of 690 m 2 /g. It was transformed to γ-Al 2 O 3 after heat treatment at 800 °C without a significant loss in surface area. DMA analysis and hotdisk thermal analysis were performed to characterize the mechanical and thermal properties of the samples. The results indicated that the alumina aerogel was robust and exhibited excellent thermal insulating properties. The elastic modulus was up to 11.4 MPa after drying, which is the one of the highest modulus of alumina aerogels ever reported. The thermal conductivities at 30 °C and 400 °C were 0.028 W/mK and 0.065 W/mK respectively.

Preparation and characterization of monolithic alumina aerogels

The thermal conductivities of silica aerogels doped with TiO2 powder and ceramic fibers were investigated by varying the gas pressure and the temperature. Doped SiO2 aerogel with a density of 260 kg m−3 has a thermal conductivity of 0.038 W m−1 K−1 at 800 K in air.

Monolithic silica aerogel insulation doped with TiO2 powder and ceramic fibers

A local electric field is induced to engineer the interface of vanadium pentoxide nanofibers (V2 O5 -NF) to manipulate the charge transport behavior and obtain high-energy and durable supercapacitors. The interface of V2 O5 -NF is modified with oxygen vacancies (Vo) in a one-step polymerization process of polyaniline (PANI). In the charge storage process, the local electric field deriving from the lopsided charge distribution around Vo will provide Coulombic forces to promote the charge transport in the resultant Vo-V2 O5 /PANI nanocable electrode. Furthermore, an ≈7 nm porous PANI coating serves as the external percolated charge transport pathway. As the charge transfer kinetics are synergistically enhanced by the dual modifications, Vo-V2 O5 /PANI-based supercapacitors exhibit an excellent specific capacitance (523 F g-1 ) as well as a long cycling lifespan (110% of capacitance remained after 20 000 cycles). This work paves an effective way to promote the charge transfer kinetics of electrode materials for next-generation energy storage systems.

Interface Engineering V 2 O 5 Nanofibers for High‐Energy and Durable Supercapacitors

Carbon black (CB) anchored vanadium oxide (C-VOx) nanobelts are successfully prepared by a simple sol–gel route and subsequent hydrothermal treatment. The synthesized C-VOx nanobelts display high specific capacity and good cycling stability as a cathode material for lithium ion batteries (LIBs) (232 mA h g−1 at initial discharge and 195 mA h g−1 during 50th discharge at a current density of 100 mA g−1 between 1.5–4 V versus Li) due to the nano-belted morphology and closely attached CB. The orthorhombic V2O5 nanobelts can be obtained by post-sintering of C-VOx nanobelts in air. These V2O5 nanobelts, which maintain their previous belted morphology and possess higher vanadium valence, exhibit superior electrochemical properties, especially the higher specific capacity (406 mA h g−1 and 220 mA h g−1 during the 1st and 50th discharge at a current density of 100 mA g−1, and 146 mA h g−1 at a current density of 1000 mA g−1 between 1.5–4 V versus Li). Both of them can be used as high performance cathode materials for LIB application. Furthermore, a full-cell using V2O5 nanobelts as the cathode and lithiated graphite as the anode is assembled and its electrochemical performance is measured in the voltage range of 1.5–3.8 V.

Carbon black anchored vanadium oxide nanobelts and their post-sintering counterpart (V2O5 nanobelts) as high performance cathode materials for lithium ion batteries

V2O5/poly(3,4-ethylenedioxythiophene) nanocables with oxygen vacancies gradually decreasing from the surface to the core (G-V2O5/PEDOT nanocables) were prepared as electrodes for supercapacitors. G...

Jichao Wang

Papers

Preparation and characterization of monolithic alumina aerogels

Monolithic silica aerogel insulation doped with TiO2 powder and ceramic fibers

Interface Engineering V 2 O 5 Nanofibers for High‐Energy and Durable Supercapacitors

Carbon black anchored vanadium oxide nanobelts and their post-sintering counterpart (V2O5 nanobelts) as high performance cathode materials for lithium ion batteries

Gradient Oxygen Vacancies in V2O5/PEDOT Nanocables for High-Performance Supercapacitors