A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g ca...A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g capacity at a rate of C/6 as well as a good cycliability. We proposed the templating mechanism based upon the precursors′ TG-DTA curves, X-ray diffraction patterns and FTIR spectra of the samples at different temperatures. A tapping-mode atomic force microscope was used to investigate the surfaces of the end products. We found that the polyacrylamide template produced metal organic compounds in the cross-linked gel precursor, and thereby modified the crystallization and particle surfaces during calcining. The template was “removed” in the end, which was partially pyrolyzed into the spiral carbon to form a conductive network with nanocrys\|talline LiFePO_4 highly monodispersed in it.展开更多
The carbon nanotube (fundamentally Single- walled carbon nanotube, SWCNT) based on 1-Amino-undecanethiol (AUT) were extremely controlled (nano-level) organizing a vertical self-assembled monolayer (SAM) on gold single...The carbon nanotube (fundamentally Single- walled carbon nanotube, SWCNT) based on 1-Amino-undecanethiol (AUT) were extremely controlled (nano-level) organizing a vertical self-assembled monolayer (SAM) on gold single crystal surfaces. The produced nano-surfaces were explored particularly by Fourier Transform Infra-red Spectroscopy (FT-IR), Cyclic Voltammetry (CV), Raman spectroscopy, Electrochemi- cal quartz crystal microbalance (EQCM), and Atomic force microscopy (AFM) techniques. The SWCNTs were initially cut (chemically) into short pipes and thiol-derivatized at the open ends. The vertical aggregation of SWCNT-AUTs on chemically refined Au(111) substrates was made-up by their spontaneous chemical bonding among carboxyl derivatized SWCNT-COOH and AUT SAM on Au(111), via peptide bonds, or directly by synthesized SWCNT-AUT composites. Raman spectroscopy and AFM surface images obviously disclosed that the SWCNT- AUT (dia. 20~40 nm) has been vertically categorized d on gold (111) substrates, shaping a SAM with a perpendicular direction.展开更多
文摘A novel templated LiFePO_4 cathode material was prepared with linear polyacrylamide, which exhibited excellent electrochemical properties, such as a 109.3 mA·h/g capacity at a rate of C/3 and a 120 mA·h/g capacity at a rate of C/6 as well as a good cycliability. We proposed the templating mechanism based upon the precursors′ TG-DTA curves, X-ray diffraction patterns and FTIR spectra of the samples at different temperatures. A tapping-mode atomic force microscope was used to investigate the surfaces of the end products. We found that the polyacrylamide template produced metal organic compounds in the cross-linked gel precursor, and thereby modified the crystallization and particle surfaces during calcining. The template was “removed” in the end, which was partially pyrolyzed into the spiral carbon to form a conductive network with nanocrys\|talline LiFePO_4 highly monodispersed in it.
文摘The carbon nanotube (fundamentally Single- walled carbon nanotube, SWCNT) based on 1-Amino-undecanethiol (AUT) were extremely controlled (nano-level) organizing a vertical self-assembled monolayer (SAM) on gold single crystal surfaces. The produced nano-surfaces were explored particularly by Fourier Transform Infra-red Spectroscopy (FT-IR), Cyclic Voltammetry (CV), Raman spectroscopy, Electrochemi- cal quartz crystal microbalance (EQCM), and Atomic force microscopy (AFM) techniques. The SWCNTs were initially cut (chemically) into short pipes and thiol-derivatized at the open ends. The vertical aggregation of SWCNT-AUTs on chemically refined Au(111) substrates was made-up by their spontaneous chemical bonding among carboxyl derivatized SWCNT-COOH and AUT SAM on Au(111), via peptide bonds, or directly by synthesized SWCNT-AUT composites. Raman spectroscopy and AFM surface images obviously disclosed that the SWCNT- AUT (dia. 20~40 nm) has been vertically categorized d on gold (111) substrates, shaping a SAM with a perpendicular direction.
