. Given that many agglomerations were formed
during the high temperature combustion synthesis, the particle
size distribution showed two obvious peaks with a median
diameter D50 of 41.75 μm before the ball milling. After 0.5 h
ball milling, the particle size moved to the left and the D50
decreased to 1.25 μm. BET surface area increased from 3.0 m2
/
g to 6.26 m2
/g with the increasing of ball milling time to 20 h.
However, the range of the particle distribution increased along