Henan Normal University

About: Henan Normal University is a education organization based out in Xinxiang, China. It is known for research contribution in the topics: Catalysis & Ionic liquid. The organization has 10863 authors who have published 11077 publications receiving 166773 citations.

Interpenetrating Triphase Cobalt-Based Nanocomposites as Efficient Bifunctional Oxygen Electrocatalysts for Long-Lasting Rechargeable Zn–Air Batteries

Abstract: Rechargeable metal–air batteries are considered as one of the most promising energy storage systems because of their high theoretical energy density, low cost, and improved safety.[1–3] However, their inferior energy conversion efficiency and low lifetimes are the main bottlenecks limiting their widespread applications.[4,5] These shortcomings predominantly originate from the intrinsically sluggish kinetics of the oxygen reduction (ORR) and evolution (OER) reactions, as well as their limited stability in harsh alkaline electrolytes.[6–8] To address the above issues, much effort has been devoted to the exploration of active and durable bifunctional electrocatalysts.[9–12] Although noble-metal catalysts, such as platinum (Pt), ruthenium (Ru), iridium (Ir), and their alloys, are regarded as the bestknown oxygen electrocatalysts, their commercialization has been greatly hindered Rational construction of atomic-scale interfaces in multiphase nanocomposites is an intriguing and challenging approach to developing advanced catalysts for both oxygen reduction (ORR) and evolution reactions (OER). Herein, a hybrid of interpenetrating metallic Co and spinel Co3O4 “Janus” nanoparticles stitched in porous graphitized shells (Co/Co3O4@PGS) is synthesized via ionic exchange and redox between Co2+ and 2D metal–organic-framework nanosheets. This strategy is proven to effectively establish highways for the transfer of electrons and reactants within the hybrid through interfacial engineering. Specifically, the phase interpenetration of mixed Co species and encapsulating porous graphitized shells provides an optimal charge/ mass transport environment. Furthermore, the defect-rich interfaces act as atomic-traps to achieve exceptional adsorption capability for oxygen reactants. Finally, robust coupling between Co and N through intimate covalent bonds prohibits the detachment of nanoparticles. As a result, Co/Co3O4@ PGS outperforms state-of-the-art noble-metal catalysts with a positive halfwave potential of 0.89 V for ORR and a low potential of 1.58 V at 10 mA cm−2 for OER. In a practical demonstration, ultrastable cyclability with a record lifetime of over 800 h at 10 mA cm−2 is achieved by Zn–air batteries with Co/ Co3O4@PGS within the rechargeable air electrode. Zn–Air Batteries

Bubble-template-assisted synthesis of hollow fullerene-like MoS2 nanocages as a lithium ion battery anode material

Abstract: Inorganic fullerene (IF)-like structured materials have attracted considerable attention for electrochemical energy storage and conversion. In this report, we describe a facile method of synthesizing IF-MoS2 hollow structures with a diameter of ∼100 nm by a facile solution-phase reduction process to obtain a hollow MoSx precursor under ambient pressures before subsequent annealing of the material at high temperatures to form IF-MoS2 nanocages. TEM images at different reaction stages reveal the hollow structure spontaneously arising in the novel “close-edge” nanocages under the assistance of an ammonia cation bubble template. When evaluated as an anode material for lithium ion batteries, ex situ characterization indicates that these IF-MoS2 hollow nanocages can provide large expandable spaces for volume changes occurring during the cycles. Such a highly desired structure offers remarkably improved lithium storage performance including high reversible capacity and good cycling behavior and high rate capability.

Observation of a Charged (D(D)over-bar*)(+/-) Mass Peak in e(+)e(-) -> pi D(D)over-bar* at root s=4.26 GeV

Abstract: We report on a study of the process e(+)e(-) -> pi(+/-) (D (D) over bar*)(-/+) at root s = 4.26 GeV using a 525 pb(-1) data sample collected with the BESIII detector at the BEPCII storage ring. A distinct charged structure is observed in the (D (D) over bar*)(-/+) invariant mass distribution. When fitted to a mass- dependent- width Breit- Wigner line shape, the pole mass and width are determined to be M-pole (3883: 9 +/- 1.5 (stat) +/- 4.2 dsyst__ MeV= c(2) and Gamma(pole) = (24: 8 +/- 3.3 (stat) +/- 11: 0 (syst)) MeV. The mass and width of the structure, which we refer to as Z(c)(3885), are 2 sigma and 1 sigma, respectively, below those of the Z(c)(3900) -> pi(+/-) J/psi peak observed by BESIII and Belle in pi(+)pi(-) J/psi final states produced at the same center- of- mass energy. The angular distribution of the pi Z(c)(3885) system favors a J(P) = J(P) = 1(+) quantum number assignment for the structure and disfavors 1(-) or 0(-). The Born cross section times the (D (D) over bar*) branching fraction of the Z(c)(3885) is measured to be sigma(e(+)e(-) -> pi(+/-)Z(c)(3885)(-/+)) x B(Z(c)(3885)-/+ -> (D (D) over bar*)(-/+) = (83.5 +/- 6.6 (stat) +/- 22.0 (syst)) pb. Assuming the Z(c)(3885) -> (D (D) over bar*)(-/+) signal reported here and the Z(c)(3900) -> pi J/psi signal are from the same source, the partial width ratio (Gamma(Z(c)(3885) -> D (D) over bar*)/Gamma(Z(c)(3900) -> pi J/psi)) = 6.2 +/- 1.1 (stat) +/- 2.7 (syst) is determined.

Liquid−Liquid Equilibria of Aqueous Biphasic Systems Containing Selected Imidazolium Ionic Liquids and Salts

Abstract: Liquid−liquid equilibrium data have been determined for imidazolium ionic liquid ([C4mim]Cl, [C6mim]Cl, [C4mim]Br, [C6mim]Br, [C8mim]Br, [C10mim]Br) + salt (KOH, K2HPO4, K2CO3, K3PO4) aqueous biphasic systems at T = 298.15 K, and in part at T = (308.15 to 318.15) K. Factors affecting the binodal curves such as nature of ionic liquids and salts and temperature are also studied. The binodal curves are fitted to a three-parameter equation, and the tie-lines were described by the Othmer−Tobias and Bancroft equations. It is found that an increase in temperature caused no significant expansion of the two-phase area. However, the binodal curves became more close to the origin with an increase in alkyl chain length of the ionic liquids (ILs), and the ionic liquids with the Br- anion are easier to form two phases compared to those with the Cl- anion. These data are expected to be useful for the development and design of the extraction process using ILs based on aqueous biphasic systems.