Janus纳米材料的制备及结构调控

用3-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPS)、 氨丙基三乙氧硅烷(APTES)和正硅酸乙酯(TEOS)溶胀聚苯乙烯中空微球的壳层, 在壳层表面通过溶胶-凝胶过程, 使亲油和亲水基团通过自组装作用分别朝向聚苯乙烯基体和水相, 形成Janus结构. 用良溶剂N,N-二甲基甲酰胺(DMF)溶解除去聚苯乙烯, 得到二氧化硅基复合Janus纳米材料. 改变反应体系pH值和单体用量等可以调控Janus纳米材料微结构, 得到Janus中空球和纳米片.

Synthesis and Morphology Control of Janus Nanomaterials†

We propose a facile method to synthesize Janus nanomaterials by seed interfacial sol-gel process against a polystyrene(PS) hollow sphere using three precursor silanes, (3-aminopropyl) triethoxysilane(APTES), methacryloxy propyl trimethoxyl silane(MPS) and tetraethyl orthosilicate(TEOS). The sol-gel process starts from the exterior surface of the seed sphere. Janus nanomaterials were formed in situ onto the seed sphere surface after a self-organized sol-gel process, which possess 3-methacryloxypropyl- and amine- groups terminated at both sides of the shell. Morphology of the Janus nanomaterials could be tunable from intact shell, nanosheet, porous nanosheet and individual nanoparticles by controlling pH, precursor amount and the fraction of binary emulsifier system. After the removal of PS by dissolution under ultrasonication, Janus nanoparticles were eventually achieved. This method is attractive owing to the easiness to continuously adjust morphology of the Janus nanomaterials. On the other hand, composition of the nanomaterials is also flexibly tunable by using different precursors. What’s more, the Janus nanomaterials can derive other Janus ones after selective modification and favorable growth of desired materials onto the corresponding side.