Changhui Zhao

Enhanced electrochemical properties of cerium metal–organic framework based composite electrodes for high-performance supercapacitor application

Cerium metal–organic framework based composites (Ce-MOF/GO and Ce-MOF/CNT) were synthesized by a wet chemical route and characterized with different techniques to characterize their crystal nature, morphology, functional groups, and porosity. The obtained Ce-MOF in the composites exhibit a nanorod structure with a size of ∼150 nm. The electrochemical performance of the composites was investigated in 3 M KOH and 3 M KOH + 0.2 M K3Fe(CN)6 electrolytes. Enhanced electrochemical behavior was obtained for the Ce-MOF/GO composite in both electrolytes and exhibited a maximum specific capacitance of 2221.2 F g−1 with an energy density of 111.05 W h kg−1 at a current density of 1 A g−1. The large mesoporous structure and the presence of oxygen functional groups in Ce-MOF/GO could facilitate ion transport in the electrode/electrolyte interface, and the results suggested that the Ce-MOF/GO composite could be used as a high-performance supercapacitor electrode material.

Synthesis of low vacancies PB with high electrochemical performance using a facile method

ABSTRACT The introduction of electric vehicles (EVs) into the automotive market has boosted the advancement of energy storage technology. Although lithium-ion batteries (LIBs) could provide a solution to the emerging EV market, it needs to overcome the issue of high material cost and limited resources. This leads the research direction to sodium-ion batteries (SIBs), the most potential alternative batteries with infinite sodium resource from the ocean and earth crust. In the current work, Prussian blue (PB) with a crystal structure of face-centered cubic is used as cathode material for rechargeable SIBs with PB size ranging from 0.5 μm to 1 μm. Low interstitial water and low vacancies PB (Na0.58Fe[Fe(CN)6]0.93γ0.07·1.67H2O) with high purity has been successfully synthesized at room temperature via a simple single iron source precipitation method. An excellent electrochemical performance has been shown with specific discharge capacity of 133 mAh g−1 and with 90% capacity retention over 200 cycles.

Influence of synthesis temperature on cobalt metal-organic framework (Co-MOF) formation and its electrochemical performance towards supercapacitor electrodes

AbstractWe have synthesized cobalt metal-organic framework (Co-MOF) at different temperatures through solvothermal route as metal-organic frameworks which can be used for supercapacitors. The effect of synthesizing temperature on Co-MOF’s structure and porous behavior were analyzed with various characterization techniques like X-ray diffraction, Brunauer-Emmett-Teller surface analyzer, scanning electron microscope, and transmission electron microscope. The charge storage performance of the as-prepared Co-MOF’s was carried out in 3xa0M KOH. The results proved the excellent redox behavior of Co-MOFs, and a maximum specific capacitance of 952.5xa0Fxa0g−1 was obtained for Co-MOF/150 (synthesized at 150xa0°C) at a current density of 0.25xa0Axa0g−1. The higher specific surface area and micropore of Co-MOF/150 significantly heightened the electrolyte ion transport during the electrochemical performance.n ᅟGraphical abstract

Fabrication of MoO x -decorated In 2 O 3 nanotubes by electron-beam irradiation

We have proposed a structural transformation method in Mo-doped In<inf>2</inf>O<inf>3</inf> nanotubes (Mo-In<inf>2</inf>O<inf>3</inf> NTs), by electron-beam irradiation with a high-resolution transmission electron microscope. Uniform Mo-In<inf>2</inf>O<inf>3</inf> NTs have been presynthesized by a facile electrospinning method and calcined in air at 600 °C. As is expected, a large number of ultrafine nanoparticles gradually generate on the surface of Mo-In<inf>2</inf>O<inf>3</inf> NTs after a few minutes of exposure to 300 kV electrons, which are further confirmed to be the crystal structure of nonstoichiometric MoO<inf>x</inf>. This approach may be meaningful for us to design some novel nanostructures and has the potential to direct nanofabrication and emerging nanodevices.