pH值调节方式对LAB辅助合成纳米Cu2O微球的影响与组装机理

以Cu(Ac)₂为原料,两性表面活性剂月桂酰胺丙基甜菜碱(LAB)为模板,采用两种不同的调节pH值方式制备了Cu₂O纳米材料.表征结果表明两种调节pH值方式均可获得Cu₂O纳米微球,并都呈立方晶相,而且样品的红外吸收峰、固体紫外吸收峰都不同程度的发生了蓝移;第一种Cu₂O纳米微球由针状纳米粒子积聚而成,针状纳米粒子间空隙孔径主要分布在25~50 nm之间,比表面积为22 m²·g^-1,禁带宽度为2.15 eV;第二种Cu₂O纳米微球由小的纳米球状体堆积而成,球状体间孔道直径集中在25~50 nm和50~125 nm两个区域,比表面积为9 m²·g^-1,禁带宽度为2.46 eV.两种不同的调节pH值方式获得的Cu₂O纳米微球,其反应历程和自组装机理存在不同.

Influence of pH Adjustment Modes on LAB Assisted-Synthesis of Cu2O Nanospheres and Self-assembly Mechanism

By two different ways of adjusting the pH value, Cu₂O nanomaterials was prepared with Cu(Ac)₂ as raw material and the ampholytic surfactant N-(3-Cocoamidopropyl)-N,N-dimethyl-N-carboxymethyl ammonium betaine (LAB) as the template. The characterization results show that Cu₂O nanometer materials obtained by two kinds of adjusting pH value belong to cubic phase, and morphology is nanospheres. In the IR and UV-Vis DRS spectra, there are different degree of blue shift of the infrared and ultraviolet absorption peak of Cu₂O nanosphere separately. The first kind of Cu₂O nanosphere is composed of acicular nanoparticles, and the size of Nanometer pore between nanoparticles is mainly distributed in 25~50 nm; the specific surface area is 22 m²·g^-1; the band gap is 2.15 eV. The second kind of Cu₂O nanospheres assembles from smaller nano-structrue globules; the size of nanometer channel among smaller nano-structrue globules are 25~50 nm and 50~125 nm; specific surface area is 9 m²·g^-1; the band gap is 2.46 eV. There are different reaction mechanism and the self-assembly mechanism of Cu₂O nanospheres obtained by two different ways of adjusting pH value.