613090.fig.004a
(a)
613090.fig.004b
(b)
613090.fig.004c
(c)
613090.fig.004d
(d)
Figure 4: SEM microstructures of the Sr4Al14O25:Eu2+,Dy3+ phosphors prepared by adding different H3BO3 contents: (a) 0 mol%, (b) 20 mol%, (c) 40 mol%, and (d) 100 mol%.