Surfactant-Coated Nanoparticle on a Stepped Surface

Metal and semiconductor particles of nanometer (nm) size feature a large surface-tovolume ratio and quantum-scale dimensions. Due to the distinct energetics of surfaces atoms and the unique energy-level structures, these nanoparticles possess extraordinary thermodynamic, chemical, electric, optical, and magnetic properties unlike those of isolated atoms and bulk systems. Equally importantly, they can be utilized as building blocks, artificial analogs of atoms in a natural crystal, to manufacture an entirely new class of materials and devices with properties unparalleled by conventional approaches and tunable by particle size. They have thus been recognized as ideal foundations of next-generation technologies in a wide range of areas. Although the bottom-up approach with nanoparticles as building blocks was conceptualized decades ago, its realization had to wait until key developments were made recently in synthesizing nanoparticles that permit controllable fabrication.