Oxygen-deficient metal–organic framework derivatives for advanced energy storage: Multiscale design, application, and future development

Fluorine-Doped Nb2O5 with Rich Oxygen Vacancies Anchored on the N/F Carbon Skeleton for Superior Lithium Storage

“…To confirm the existence of oxygen vacancies in materials, EPR spectroscopy is the most efficient method to detect oxygen vacancies. As revealed in Figure i, a sharp and high signal peak at the position of g = 2.003 can be detected in F–Nb 2 O 5 @NFC, which is a characteristic peak belonging to oxygen vacancy. − However, there is no oxygen vacancy signal peak in the Nb 2 O 5 @NC and Nb 2 O 5 @C composites. It can be concluded that F-doping is an important factor to create oxygen vacancies in the Nb 2 O 5 lattice.…”

“…In the crystal, ions and electrons are transferred by jumping between lattice points, and oxygen vacancies in the lattice can be used as carriers to transfer charges. In addition, the introduction of oxygen vacancies can increase the concentration of free ions, which together improve the intrinsic conductivity of metal oxides. − To sum up, F-doping and introduced oxygen vacancies increase the free ion concentration of the Nb 2 O 5 crystal, accelerate the charge transfer, and greatly improve the intrinsic conductivity of Nb 2 O 5 , and the conductive network provided by NFC accelerates the transmission of electrons. Therefore, the F–Nb 2 O 5 @NFC electrode is expected to obtain an excellent lithium-ion storage performance.…”

In situ construction of core–shell structured cobalt oxide@nickel–cobalt-layered double hydroxide nanorods with abundant oxygen vacancies towards boosting electrochemical energy storage

“…The incorporation of vacancy engineering, such as introducing oxygen vacancies, has the potential to greatly boost the electrochemical performance by simultaneously improving both the OH − absorption capacity and electronic conductivity. 13–16 For example, Zou et al synthesized NiMn-LDH (Ov-LDH) by mild H 2 O 2 treatment. 17 When compared to a pure NiMn LDH electrode, the synthesized electrode performed better with a specific capacitance of 1183 C g −1 at 1 A g −1 .…”

A Review on Covalent Organic Frameworks as Artificial Interface Layers for Li and Zn Metal Anodes in Rechargeable Batteries

“…At present, rechargeable batteries have been widely used in electric vehicles, medical devices, electronic products, and military equipment because of the successful commercialization of Li‐ion batteries (LIBs) in the 1990s. [ 8–11 ] Since the commercialization of LIBs, they have dominated the market for decades, particularly in electric vehicles and portable electronic products, because of their advantages, including high efficiency, long lifespan, and low maintenance costs. [ 12–14 ] However, traditional LIBs are expensive and have low energy density, thus limiting their applications.…”