以SDS-PVP项链状软团簇为模板简易一锅法合成Cu2O中空亚微球

在SDS-PVP水溶液中采用N2H4•H2O还原CuSO4, 在pH (10±0.5), (40±1.0) ℃条件下反应55 min得到橙色Cu2O溶胶, 离心分离产物经XRD鉴定为Cu2O立方晶系晶体; SEM和TEM表明该法获得的晶体为形状规整、粒径分布窄的Cu2O中空亚微球, 并证实系由大量10 nm量级的原级Cu2O纳米晶粒组装而成. 根据实验事实推断, SDS-PVP项链状软团簇提供了“双重软模板”功能, 借助独特的“模板诱导两级组装”作用一锅法合成了Cu2O中空亚微球. Cu2O中空亚微球生长的可能途径为: 首先, 项链状软团簇中的SDS束缚胶束作为第一重软模板, 诱导一级组装10 nm量级的原级Cu2O纳米晶粒; 然后, 软团簇中立体桥联SDS束缚胶束的PVP链节作为第二重软模板, 诱导一定空间范围内的原级Cu2O纳米晶粒长大并进一步聚集/二级组装, 经一锅法合成得到次级Cu2O中空亚微球. 实验结果证明该一锅法温和、简便、快捷, Cu2O中空亚微球的粒径分布窄.

A Facile One-pot Synthesis of Hollow Cu2O Submicrospheres in Virtue of Template Function of the SDS-PVP Necklace-like Soft Clusters

Orange cuprous oxide (Cu2O) colloids were prepared in the process of reducing copper sulfate (CuSO4) by hydrazine hydrate in aqueous solution of sodium dodecyl sulfate (SDS)-polyvinylpyrrolidone (PVP) in the conditions of pH (10±0.5) and (40±1.0) ℃ for 55 min. XRD pattern displays that the centrifuged reduced products are pure cubic Cu2O crystals. SEM and TEM images show that the reduced products are hollow Cu2O submicrospheres with regular morphology and controlled size, and confirm that the hollow submicrospheres are composed of primary Cu2O nanocrystals with diameters of ca. 10 nm. The experiment supposed that the SDS-PVP necklace-like clusters perform a function of dual soft-template that results in a unique template-induced secondary assembly, through which one-pot synthesis of hollow Cu2O submicrospheres was completed. The possible one-pot synthesis route was thought as divided into two steps. At first, the primary Cu2O nanocrystals with average size of 10 nm are synthesized in SDS bound-micelles that are used as the primary soft-template. Then, the PVP chains play the role of the secondary soft-template which makes the primary Cu2O nanocrystals, in a certain space, aggregated and fabricated. The secondary hollow Cu2O submicrospheres are thus synthesized in one-pot in virtue of the PVP chains that will originally couple SDS bound-micelles three-dimensionally. The experiment results show that the one-pot synthesis is a gentle, facile and fast way to prepare the hollow Cu2O submicrospheres with narrow size-distribution.