Experimental details
Materials synthesis. The MnC2O4 wires were synthesized by a confined
precipitation reaction in microemulsion. In brief, a quaternary microemulsion was
first prepared by dissolving cetyltrimethyl ammonium bromide (CTAB, 4.0 g) in a
mixture of cyclohexane (150 mL), n-pentanol (5.0 mL), and oxalic acid aqueous
solution (7.5 mL, 0.8 M). After constant stirring for 30 min, Mn(CH3COO)2 aqueous
solution (2.5 mL, 0.2 M) was dripped and the resulting microemulsion was vigorously
stirred for 2 h at room termperature. The white MnC2O4 precursors were filtered,
washed with ethanol, and vaccum-dried.
The porous Mn2O3 wires were obtained by thermal decomposition of the MnC2O4
wires at 500 oC for 10 hours. To obtain LNMO nanorods, 12 mmol of Mn2O3 wires,
8.3 mmol Li CH3COO •2H2O, 4 mmol Ni(CH3COO)2•4H2O were dispersed in 10 mL
of ethanol. The ethanol was evaporated slowly at room temperature under stirring.
The remained solid was ground manually for 10 minutes and the calcined at 700 oC
for 6 hours in air.
The bulk LNMO was prepared by a simple coprecipitation method. In a typical
synthesis route, LiCH3COO•2H2O, Ni(CH3COO)2•4H2O, and Mn(CH3COO)2•4H2O
in molar ratio of 1.03:0.5:1.5 and in quantities corresponding to 0.9 g LNMO were
dissolved in 20 mL of water. The solution was heated to 50 oC and then 3 mL of
PEG400 was added. Under constant stirring, 2.0 g H2C2O4•2H2O was added to the
solution, and then heated to 90 oC to evaporate water. The obtained solid was calcined
at 900 oC under air atmosphere for 10 h, follow by reannealing at 700 oC for 20 h in
4
air to obtain the ordered bulk LNMO.
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