Surface functionalization on nanoparticles via atomic layer deposition

As an ultrathin film preparation method, atomic layer deposition (ALD) has recently found versatile applications in fields beyond semiconductors, such as energy, environment, catalysis and so on. The design, preparation and characterization of thin film applied in the emerging fields have attracted great interests. The development of ALD technique on particles opens up a broad horizon in the advanced nanofabrication. Pioneering applications are exploring conformal coating, porous coating and selective surface modification of nanoparticles. Conformal encapsulation of particles is a major application to protect materials with ultrathin films from being eroded by the external environment while keeping the original properties of the primary particles. Porous coating has been developed to simultaneously expose the particles' surface and provide nanopores, which is another important method that demonstrates its advantages in modification of electrode materials, catalysis and energy applications, etc. Selective ALD takes the method forward in order to precisely control the directionality of decoration sites on the particles and selectively passivate undesired facets, sites, or defects. Such methods provide practical strategies for atomic scale and precise surface functionalization on particles and greatly expand its potential applications.