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101.
Non-noble bifunctional electrocatalysts with robust activity and stability toward oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are greatly significant but challenging for Zn-air batteries. Here, in situ confinement of FeNx active sites in high porosity carbon framework (FeNx/CMCC) derived from chelate of carboxymethylcellulose (CMC) and iron ions were synthesized. Particularly, construction of FeNx within porous carbon framework accelerates the electron transfer and the sufficient utilization of active centers, and then expedites the reaction kinetics of ORR and OER. As expected, the optimized FeNx/CMCC exhibits superior ORR activity with a larger half-wave potential of 0.869 V. The rechargeable Zn-air battery delivers a higher power density of 99.6 mW/cm2 and a special capacity of 781.9 mA h/gZn at 10 mA/cm2, together with excellent durability of over 335 h. Remarkably, the as-assembled solid-state battery exhibits a higher open circuit voltage (OCV) of 1.5 V, a special capacity of 709.7 mA h/gZn, as well as prolonged cycling stability (90 h). Moreover, the flexible solid-state battery displays negligible loss of electrochemical performance under various bending angles, illustrating its potential application in flexible electronic devices. 相似文献
102.
Siberian Mathematical Journal - For a hyperbolic equation of the second order, we consider the inverse problem of recovering the coefficient $ q(x,y) $ in this equation. We discuss the... 相似文献
103.
JETP Letters - The nonlocal Darboux transformation for the time-independent axially symmetric Schrödinger and Helmholtz equations has been considered. New examples of two-dimensional... 相似文献
104.
Isaeva A. I. Maikov E. Gibizova V. V. Petrova G. P. 《Journal of Applied Spectroscopy》2021,88(4):789-793
Journal of Applied Spectroscopy - Aqueous solutions of human hemoglobin have been studied by the multi-angle static light scattering method. The tendency of sickle-shaped erythrocytes to aggregate... 相似文献
105.
Crystallography Reports - A novel 3D metal coordination polymer, {[Na4(µ2-H2O)(DMF)2(BCT)2]?DMF}n (I) (DMF = N,N-dimethylformamide, H2BCT =... 相似文献
106.
Shklover V. Ya. Kazanskii P. R. Artemov N. A. Maryasev I. G. 《Crystallography Reports》2021,66(4):663-672
Crystallography Reports - The development of fundamental and applied geology requires an ever-increasing amount of data on the structures and properties of rocks at different scales. Of particular... 相似文献
107.
Fluid Dynamics - To predict the boundary layer transition on swept wings, experimental and numerical researches were conducted to obtained the accurate boundary layer transition front and to... 相似文献
108.
Doklady Physics - Forced linear oscillations of dissipative mechanical systems with two degrees of freedom under the action of time-periodic forces are considered. The Lagrange equations are... 相似文献
109.
Technical Physics - The structures of carbon nanotubes synthesized by catalytic CVD in the same reactor using different carbon-containing precursors and a FeCl3 catalyst have been compared. Methane... 相似文献
110.
Transport in Porous Media - The theme of coupling problems for adsorption, absorption and thermochemical transport in porous media is very important for engineering applications. Based on the... 相似文献