Figure 2

(a) SEM images and the elemental distribution of AgSbTe₂ ingots quenched after melting; the region of grain boundaries was identified as Ag₂Te precipitates, (b–e) SEM images of the hot-pressed samples; the light and dark regions are Ag₂Te precipitates and AgSbTe₂ matrix, respectively; the precipitates crushed from melted ingots remained as isolated precipitates in the sintered samples, (b) AgSbTe₂, (c) x = 0.002, (d) x = 0.003, and (e) x = 0.004 samples in AgSb_1−xCe_xTe₂.