Fig. 1 shows a typical XRD pattern of each sample. The welldefined
reflection peaks include eight lattice planes at (111),
(311), (222), (400), (331), (511), (440) and (531), which are indexed
to the cubic structure of spinel LiMn2O4 (JCPDS File No. 35-0782)
with the Fd3m space group. No impurity phase can be detected in
the XRD pattern and it also indicates that Al substituting of Mn does
not change the spinel structure of LiMn2O4. In the axis of 2q, the
curves of the Al doped LiAlxMn2xO4 spinel exhibits a rightward
shift compared with pristine LiMn2O4, and the degree of rightward
shift becomes bigger with the increasing Al content, which results
in the shrinkage of spinel lattice [24]. The calculated crystal
parameter of prepared LiAlxMn2xO4 is listed in Table 1. It can be
found from Table 1 that the lattice parameter of cathode materials
gradually decreases with the increasing Al content, and it also
proves that Al3þ ions were successfully doped into the crystal lattice
of LiMn2O4. The result is in accordance with that the lattice
parameter of LiMgxMn2-xO4 prepared by the solid-state combustion
synthesis decreases linearly with the increase of Mg-doping
content when x < 0.10 [23]. It is due to that partial amount of the
relatively larger Mn3þ ions (ri ¼ 0.65 Å) are substituted by the
smaller Al3þ ions (ri ¼ 0.54 Å) [20]
Fig. 1 shows a typical XRD pattern of each sample. The welldefinedreflection peaks include eight lattice planes at (111),(311), (222), (400), (331), (511), (440) and (531), which are indexedto the cubic structure of spinel LiMn2O4 (JCPDS File No. 35-0782)with the Fd3m space group. No impurity phase can be detected inthe XRD pattern and it also indicates that Al substituting of Mn doesnot change the spinel structure of LiMn2O4. In the axis of 2q, thecurves of the Al doped LiAlxMn2xO4 spinel exhibits a rightwardshift compared with pristine LiMn2O4, and the degree of rightwardshift becomes bigger with the increasing Al content, which resultsin the shrinkage of spinel lattice [24]. The calculated crystalparameter of prepared LiAlxMn2xO4 is listed in Table 1. It can befound from Table 1 that the lattice parameter of cathode materialsgradually decreases with the increasing Al content, and it alsoproves that Al3þ ions were successfully doped into the crystal latticeof LiMn2O4. The result is in accordance with that the latticeparameter of LiMgxMn2-xO4 prepared by the solid-state combustionsynthesis decreases linearly with the increase of Mg-dopingcontent when x < 0.10 [23]. It is due to that partial amount of therelatively larger Mn3þ ions (ri ¼ 0.65 Å) are substituted by thesmaller Al3þ ions (ri ¼ 0.54 Å) [20]
การแปล กรุณารอสักครู่..