Quality manufacture beats quality control
For semiconductor nanocrystals, tight control over particle size is needed to obtain particles with uniform properties. However, post-synthesis purification methods can be difficult and costly. Hendricks
et al.
present a family of substituted thioureas as a class of chalcogen precursors (see the Perspective by Hens). The rate of reactivity is connected to the specific chemistry of the precursor, making it possible to synthesize metal chalcogenide nanocrystals, such as PbS, with a specific size, narrow size distribution, and full conversion of the reactants.
Science
, this issue p.
1226
; see also p.
1211
制造质量胜过质量控制
对于半导体纳米晶体,需要对粒子尺寸进行严格控制,以获得具有均匀性能的粒子。然而,后合成纯化方法可能会很困难且昂贵。Hendricks等人提出了一类硫脲替代物作为硒烯前体的家族(见Hens的观点)。反应速率与前体的特定化学性质相关,这使得可以合成金属硒化物纳米晶体,例如PbS,具有特定尺寸、窄尺寸分布和反应物的完全转化。
《科学》本期p. 1226;另见p. 1211