10.1016/j.jallcom.2016.05.264
Multi-shelled NiO hollow spheres: Easy hydrothermal synthesis and lithium storage performances

Synthesis of multi-shelled NiO hollow spheres: In a typical experiment, 0.01 mol d-glucose and 0.02 mol Ni(NO3)2*6H2O were dissolved in 50 ml utrapure water. Then, the solution was homogenized by vigorous stirring. After stirring for 30 min, the resultant mixture was transferred to a 100 ml Teflon-lined autoclave followed by hydrothermal treatment at 180 degC for 20 h. The obtained products were washed and filtered off several times using utrapure water and ethanol successively, and finally dried in a vacuum oven at 80 degC for 12 h. After synthesis, the products were subjected to annealing at 270, 350, 430 or 550 degC for 3 h in air with a heating rate of 2 degC min-1 from room temperature to obtain multi-shelled NiO hollow spheres with a controlled number of shells (solid NiO sphere, double-, triple- and quadruple/quintuple-shelled NiO hollow sphere, respectively).
d-glucose
dissolved
0.01 mol
mol
Ni(NO3)2*6H2O
dissolved
0.02 mol
mol
utrapure water
50 ml
ml
Teflon-lined autoclave
100 ml
ml
resultant mixture
hydrothermal treatment
180 degC
degC
resultant mixture
hydrothermal treatment
20 h
h
products
dried
80 degC
degC
products
dried
12 h
h
products
annealing
270, 350, 430 or 550 degC
degC
products
heating rate
2 degC min-1
degC min-1
products
annealing
3 h
h