24小时热门版块排行榜

返回列表

当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

tl-tomorrow

金虫 (小有名气)

应助: 0 (幼儿园)
金币: 697
帖子: 51
在线: 105.1小时
虫号: 3505257

[交流] 纳米材料三角形片状的生成机理

有人了解为什么片状纳米材料长成正三角形的机理吗？我看到很多化学气相沉积得到的是三角形的片。我自己做的一些团簇也有组装成三角形的片，也有成矩形的片。

回复此楼

» 猜你喜欢

什么脱膜剂可以完全清洗干净啊？已经有2人回复
暨南大学化学与材料学院赵宇亮院士正在招博士和博后，方向为生物材料和纳米医学已经有1人回复
有机高分子材料论文润色/翻译怎么收费? 已经有220人回复
可生物降解聚酯正在重塑现代医疗器械已经有0人回复
26届博士申请已经有2人回复
PLLA 微球在生物医学领域的研究与应用已经有1人回复
PLLA 微球的材料特性与制备工艺解析已经有0人回复
医用聚己内酯（PCL）全解析：从两段式降解到组织工程应用已经有0人回复
反相硅胶如何再生？已经有1人回复

» 本主题相关商家推荐: (我也要在这里推广)

» 抢金币啦！回帖就可以得到:

查看全部散金贴

1楼 2020-07-16 01:02:45

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

tantaixing

金虫 (正式写手)

应助: 6 (幼儿园)
金币: 1553.6
帖子: 484
在线: 383.5小时
虫号: 965643

★
tl-tomorrow(金币+2): 谢谢参与

这个也材料晶面原子排列方式有关。你所举例子是fcc结构的贵金属，很容易形成三角片，六角片的形貌。所暴露的（111）晶面方向，是六方点阵。可以是三角形也可以是六边形。

赞一下

回复此楼

9楼2020-07-17 09:10:48

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

查看全部 13 个回答

tl-tomorrow

金虫 (小有名气)

应助: 0 (幼儿园)
金币: 697
帖子: 51
在线: 105.1小时
虫号: 3505257

When a single twin plane is formed, the resulting nucleus, at the early stage of growth, is a hexagonal plate due to the 6-fold symmetry of fcc structures (Figure 13). Each side of the hexagon is either a concave side or a convex side because of the presence of a twin plane. When atoms diffuse toward the nucleus and adsorb to grow the NC, they can adsorb either on a concave or on a convex face. On the convex side, each atomic site has only three closest neighbors, and the stabilization energy is therefore quite low. On the other hand, on the concave side, newly adsorbed atoms are stabilized by four neighbors from several facets, increasing the stabilization energy. Atoms will then preferentially adsorb on the concave sides, favoring the growth of the NC along these sides rather than the convex sides. The growth will be favored on the facets that present a concave-type surface, while the convex-type surface does not favor adsorption of new atoms and will remain unchanged. This can also be explained by the Gibbs−Thomson formula which states that the chemical potential is inversely proportional to the curvature. Δμ γ = Ω + (1/ R1+1/ R2)
where Δμ is the change in the chemical potential, γ the interfacial free energy, Ω the atomic volume, and R1 and R2 are the radii curvature.2 For a convex surface where the curvature is positive, the chemical potential change is positive and the adsorption of atoms is favored on a flat surface rather that a convex surface. On the other hand, for a concave surface where the curvature is negative, the change in the chemical is negative and the adsorption of atoms on the concave side is favored.