质谱在纳米材料成分及粒径分析中的应用

Application of Mass Spectrometry in Component and Particle Size Analysis of Nanomaterials

粒度和化学组成是纳米材料的基本参数,其中,纳米级尺寸赋予了纳米材料不同于块体材料的特殊性能,如表面和界面效应、小尺寸效应、量子尺寸效应、宏观量子隧穿效应和介电约束效应等;化学成分和含量决定了纳米材料的化学活性、催化选择性、吸附选择性和生物亲和性等化学性质。二者在很大程度上决定了纳米材料在能源、电子、环境、传感、生物医药等领域的应用。因此,纳米材料的粒径和成分分析对其制备过程优化和应用具有重要意义。质谱几乎可以分析所有类型、所有形式的材料,具有分析精度和检测灵敏度高的特点,在纳米涂层厚度、纳米材料组成、痕量杂质和成分分布等分析中有着广泛应用。最近,质谱被用于分析纳米颗粒数量浓度、粒径和粒径分布,展现了其在大尺寸范围的悬浮液中进行粒度测量的潜力。本文综述了质谱技术在纳米材料成分及粒径分析中取得的进展,通过介绍适用于纳米材料分析的电感耦合等离子体质谱、辉光放电质谱、二次离子质谱和基质辅助激光解吸电离质谱技术的基本原理、优缺点、适用范围及应用,展示其在纳米材料表征中的潜力。同时,还总结了质谱技术在环境干扰、复杂形貌颗粒粒径表征、成分空间分辨和原位分析等方面面临的挑战,并提出通过研发针对纳米材料的专用仪器、与其他分离检测技术相结合等策略克服上述问题,力图为纳米材料质谱表征技术的发展提供参考。

Particle size and chemical composition are the basic parameters of nanomaterials.The nanoscale size endows nanomaterials with special properties different from bulk materials,such as surface and interface effect,small size effect,quantum size effect,macroscopic quantum tunneling effect and dielectric confinement effect.The type and content of chemical components determine the chemical properties of nanomaterials,such as chemical activity,catalytic selectivity,adsorption selectivity and biological affinity.To a large extent,particle size and chemical composition determine the application of nanomaterials in energy,electronics,environment,sensing,biomedicine and other fields.Therefore,the particle size and composition analysis of nanomaterials are of great significance for the optimization and application of their preparation process.Mass spectrometry is one of the main analytical techniques,which is used to detect the mass,elemental composition and chemical structure of particles or molecules,and it can analyze almost all types and forms of materials,with the characteristics of high analysis accuracy and high detection sensitivity.It has been more widely applied in nano-coating thickness analysis,nanomaterials composition analysis,trace impurity analysis and composition distribution analysis.In some recent research studies,mass spectrometry has also been used to analyze the number concentration,particle size and particle size distribution of nanoparticles,demonstrating its potential for particle size measurements in suspensions over a large size range.In this paper,the advances in studies on mass spectrometry in the analysis of the composition and particle size of nanomaterials were reviewed.The basic principles,advantages and disadvantages,range of application and application cases of inductively coupled plasma mass spectrometry,glow discharge mass spectrometry,secondary ion mass spectrometry and matrix-assisted laser desorption ionization mass spectrometry techniques applicable to the analysis of nanomaterials were introduced,demonstrating the potential of mass spectrometry in the characterization of nanomaterials.Finally,this paper summarized the challenges faced by mass spectrometry analysis technology in environmental interference,size characterization of particles with complex morphology,spatial resolution of components and in-situ analysis.The strategies to overcome the above problems by designing special instruments for characterization of nanomaterials and combining with other separation and detection techniques were proposed,trying to provide some reference for the development of mass spectrometry characterization techniques of nanomaterials.