Nano Reports is a scholarly open-access, peer-reviewed, international and interdisciplinary research journal with a wide-ranging coverage of nanoscience and nanotechnology. Submissions are solicited in all topical areas, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials.
of ordered mesoporous carbon CMK-3 with excellent ORR performance
using Polyacrylonitrile (PAN) as a precursor
Author: Chunyun Yan1, Fang Yuan2, Jing Wu1, Jin Sun1 *, Hongwei Wang1 *, Xilin She1*
Abstract: Ordered mesoporous carbon has become a promising material because of its high surface area, strong conductivity and excellent stability. These characteristics are just in line with efficient oxygen reduction reaction electrode material catalyst. In this report, we designed a novel method to synthesize ordered mesoporous carbon CMK-3 using PAN as a precursor. Different from the traditional synthesis of mesoporous carbon with sucrose as precursor, the introduction of nitrogen element in PAN can further enhance the electrocatalytic performance of the material.
Keywords: Ordered mesoporous carbon; Polyacrylonitrile; Sucrose; Oxygen reduction reaction.
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Li(NixCoyMnz)O2 (x= 0.4, 0.333 and 0.2) porous
multishelled fibers as High-Performance Cathode Materials for Li-Ion
Author: Yihui Zou1, Chen Yang1, Liying Liu1, Jin Sun2*
Abstract: In this essay, we deliver the synthesis of a sequence of Li(NixCoyMnz)O2 (x= 0.4, 0.333 and 0.2) porous multishelled fibers using sustainable seaweed (alginate) fiber as template. The introduction of Ni, Co, and Mn atoms was carried out via a facile ion-exchange process, where the M2+(M = Ni, Co, Mn) cations are able to be immobilized into a novel “egg-box” via coordination with negatively charged α-L-guluronate (G) blocks of liner alginate macromolecule. Likewise, Li+ was absorbed on the β-D-mannuronate (M) blocks in alginate by the negatively charged carboxyl. When heating the Li-M alginate fibers (Li-M-AFs) in air, the metal ions inclines to aggregate on the surface of fiber, and heterogeneous contraction of the fiber caused by the non-equilibrium heat treatment and the carbon combustion lead to the formation of multishelled fiber. More importantly, the wall of the multishelled fiber could transform to novel multishelled structure because of typical Kirkendall-Effect, and hence Li(NixCoyMnz)O2 porous multishelled fibers with controllable Ni content (x = 0.2, 0.333 and 0.4 ) were successfully fabricated. As we expected, the one-dimensional (1D) Li(NixCoyMnz)O2 porous multishelled fibers present excellent capacity retention of 94.09 % after 100 cycle numbers (x = 0.333).
Keywords: alginate; porous multishelled fiber; Li-ion battery; cathode material; Li(NixCoyMnz)O2
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