小中大【转载】【求助】HRTEM-SAED---审稿人提出的问题
请教电镜高手2个问题
(1) “The cubic morphology of fig. A shows an evident [100] orientation parallel to the electron beam (under the assumption that we are in presence of a single-crystal-like features, as the authors wrote), while, instead, the corresponding ED pattern is related by the authors to the zone axis [111].
对此问题,我想回答如下: 从SEM和TEM上看,我们得到的是小粒子聚集而成的不规则空心结构。有些粒子明显呈近似八面体形貌。图A的形貌也可能是八面体(备注:我们文章没有提到cube形貌)的投影,所以对应的ED是沿着[111]入射方向衍射结果。
“the lattice imaging of figure clearly evidence the presence of polycrystalline features; the authors wrote that the “hollow nanocrystals are not perfect single crystals but with highly oriented, single-crystal-like features”, a significant part of the imaged area appears amorphous-like, but the quality of XRD patters evidence a scarce presence of amorphous materials and, as a consequence, this can be attributed to the presence of nanocrystallites with an orientation out of zone-axis
审稿人的意思是,“空心结构是不完美的单晶”-但在HRTEM中有很明显的amorphous,但XRD没有出现amorphous的峰,因此这是由于an orientation out of zone-axis。
审稿人说的没错,但是HR-TEM晶格条纹在orientation out of zone-axis条件下不出现,和我们提出的“空心结构是不完美的单晶”以及上面的SAED标记有和关系吗?二者矛盾吗?
(备注:图A显示,虽然明显有小粒子聚集而成,但对应的SAED (B)显示结晶有序性特别好-- single-crystal-like features)
谢谢,祝朋友圣诞快乐