Metal nanoparticle dispersion refers to the dispersion of one or more metal nanoparticles in another liquid medium. Monodisperse nanoparticle materials are a new generation of nanomaterials developed in the research process of nanomaterials. Their particles are small and uniform, without agglomeration, and can be dispersed in solvents to form nano-dispersions with good transparency or obvious Tyndall effect. Compared with traditional nano-powder materials, nano-powder materials are easier to disperse and apply, thus showing better optical, electrical, magnetic, mechanical, acoustic and catalytic properties, so the research on their preparation and application properties has always been an international cutting-edge research field.
Figure 1. Proposed reaction pathway for coupling of nitroaromatic compounds.
Figure 2. Schematic diagram of the synthesis of a tungsten bronze nanoparticle.
In addition, metal nanodispersions are expected to play a more important role in petrochemical, fine chemical, aerospace, energy environment, flexible wearable devices and other application fields.
The preparation of metal nanodispersion can be divided into physical dispersion method (such as emulsification-solvent volatilization method, etc.) and chemical reaction method (such as polymerization method). The dispersion principle is mainly divided into the following categories: (1) Enhance the repulsive energy between metal nanoparticles. (2) Strengthen the wettability of the nanoparticle surface to the dispersion medium and change its interface structure. (3) Improve the strength and thickness of the solvated film and enhance the solvent repelling effect. (4) Increase the absolute value of the potential of the electric double layer on the surface of the nanoparticles, and enhance the electrostatic repulsion between the nanoparticles. (5) Adsorbed on the surface of nanoparticles by polymer dispersant to produce and strengthen the three-dimensional protection.
References