基于微流控芯片的ZnO纳米刷结构的可控合成方法

Controllable Synthesis Method Based on Microfluidic Chips for ZnO Nanobrush Structures

合成方法和合成环境对ZnO纳米结构的直径和形貌具有重要影响。研究了采用直接生长法和二次种子法在传统环境和微流控芯片中制备的ZnO纳米结构的直径和形貌差异。结果表明,不同的合成方法和合成环境所制备的ZnO纳米结构直径和形貌不同,二次种子法在传统环境和微流控芯片中均可实现ZnO纳米刷结构的制备。其中,二次种子法在微流控芯片中可以实现对ZnO纳米刷结构的快速制备,主干和分支的平均横向生长速率分别为457.4和304.8 nm/h。所制备的ZnO纳米刷结构分布更均匀、取向性好,且纳米分支在主干侧面均匀密集分布,具有良好的取向性。此外,研究了不同浓度的一次种子溶液对ZnO纳米结构的直径和形貌的影响。结果表明,浓度为1 mmol/L的一次种子溶液可以有效促进二次生长过程中分支成核和分支生长。实验结果证明,在微流控芯片中可以构建连续流反应器,通过对合成参数和流体运动的精准调控,可实现对ZnO纳米刷结构的低成本、快速、可控合成。

The synthesis method and environment greatly affect the diameter and morphology of ZnO nanostructures.The differences in diameter and morphology of ZnO nanostructures prepared by direct growth method and secondary seed method in conventional environment and microfluidic chips were studied.The results show that the diameters and morphologies of the ZnO nanostructures prepared by different synthesis methods and environments are different,and the ZnO nanobrush structures can be obtained via the secondary seed method in both conventional environment and microfluidic chips.Among them,the secondary seed method can achieve rapid preparation of the ZnO nanobrush structures in microfluidic chips,the average lateral growth rates of the trunk and branches are 457.4 and 304.8 nm/h,respectively.The prepared ZnO nanobrush structures have more uniform distribution and good orientation,and the nanobranches are evenly and densely distributed on the side of the trunk,showing good orientation.In addition,the effects of different concentrations of primary seed solution on the diameter and morphology of the ZnO nanostructures were studied.The results show that the primary seed solution with a concentration of 1 mmol/L can effectively promote branching nucleation and growth during the secondary growth process.The experimental results show that the continuous flow reactor can be constructed in microfluidic chips to achieve low-cost,rapid and controllable synthesis of ZnO nanobrush structures through precise control of synthesis parameters and fluid motion.