Surface functionalized nanoparticles refer to the treatment, modification and processing of the surface of nanoparticles by physical, chemical and other deep processing methods to control their internal stress, increase the repulsion of nanoparticles, reduce the attraction between particles, and purposely change the surface physical and chemical properties of the nanoparticles to give the nanoparticles new functions to meet their processing and application needs.
The unmodified nanoparticles have fine particle size, large specific surface area, high surface energy, increased surface atom number, insufficient atomic coordination and high surface energy, making these surface atoms highly active and extremely unstable. During the preparation and use of nanoparticles, they are easy to agglomerate or adsorb with other substances. Surface functionalized nanoparticles can improve or enhance the compatibility between inorganic nanoparticles and the substrate or other substances in the composite materials. The applications in the fields of catalysis, environmental protection, microelectronics, biomedicine and chemical industry requires nanoparticles with specific surface physicochemical properties and functions.
Figure 1. Examples of nanomaterials and their functional groups for biological applications.