微波水热法制备不同形貌的PbS纳米晶

Synthesis of PbS nanocrystals with different shapes via microwave hydrothermal method

纳米晶的形貌对其性能有很大的影响,形貌调控一直是纳米晶合成工艺中的重要环节.在文献报道中,硫化铅纳米晶(PbSNCs)的形貌调控大多依靠改变配体分子的类型或使用模板分子,制备过程较复杂,且具有随机性.实验使用β-乳球蛋白作为配体,合成了立方相的PbSNCs.通过调节β-乳球蛋白和Pb^(2+)的混合时间,干预配体与前驱体离子的螯合时间,从而进一步影响后续的晶体生长.当预混合时间为6 h时,得到纳米棒形貌;不进行预混合时,得到纳米球形貌;预混合时间为1 h时,得到纳米花形貌.建立了一种简单易行的调控纳米晶形貌的方法,并证实了蛋白大分子作为纳米晶配体的可行性及其良好的调控作用.

The morphology of the nanocrystals can greatly affect their properties.Morphology regulation has always been an important link in the synthesis of nanocrystals.In the previous reports,the morphology regulation of lead sulfide nanocrystals(PbS NCs)has been realized by changing the ligands,or using template molecules.However,the preparation process is complex and random.In this work,β-lactoglobulin was used as the ligand for synthesis of cubic PbS NCs.By adjusting the mixing time ofβ-lactoglobulin and Pb^(2+) to affect the chelation time between the ligand and precursor ions,the subsequent crystal growth was affected.PbS NCs with the morphologies of nanodots,nanoflowers,and nanorods were obtained via mixingβ-lactoglobulin with Pb^(2+) for 0 h,1 h,and 6 h,respectively.It means that a simple method to regulate the morphology of nanocrystals was established,and the feasibility and good regulation of protein macromolecules as nanocrystalline ligands were confirmed.