Carbon-coated nanophase CaMoO4 as anode material for Li ion batteries
Pure and carbon (C)-coated CaMoO4 were synthesized by solution precipitation and solgel methods, and their electrochemical properties were studied vs Li by galvanostatic cycling and cyclic voltammetry (CV). Combined X-ray diffraction, SEM...
| Հիմնական հեղինակներ: | , , , , , |
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| Այլ հեղինակներ: | |
| Ձևաչափ: | Journal Article |
| Լեզու: | English |
| Հրապարակվել է: |
2012
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| Խորագրեր: | |
| Առցանց հասանելիություն: | https://hdl.handle.net/10356/94292 http://hdl.handle.net/10220/7447 |
| Ամփոփում: | Pure and carbon (C)-coated CaMoO4 were synthesized by solution precipitation and solgel
methods, and their electrochemical properties were studied vs Li by galvanostatic cycling
and cyclic voltammetry (CV). Combined X-ray diffraction, SEM, and TEM results revealed
the formation of nanocrystalline particles with the scheelite structure, the morphology being
a function of the synthetic procedure. TEM of 10% C-coated CaMoO4 shows the amorphous
nature of carbon on the crystalline particles with a thickness of 8-12 nm. Galvanostatic
data in the voltage range of 0.005-2.5 V up to 50 cycles at a rate of 60 mA/g revealed that
the 10% C-coated CaMoO4 gave the highest reversible capacities. At the 20th discharge cycle,
the capacity values (mA h/g) are as follows: solution precipitated, 190; sol-gel, 268; 5%
C-coated, 401; and 10% C-coated, 508. The latter value corresponds to 3.8 mol of recyclable
Li. The improvement in the interparticle electronic conductivity imparted by the C-coating
led to superior performance. The Coulombic efficiency for all the compositions is >98%.
Galvanostatic cycling results are supplemented by the CV data. A plausible mechanism for
charge-discharge cycling has been proposed. |
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