Review paper: Semiconductor nanoparticles with surface passivation and surface plasmon

Semiconductor nanoparticles have recently attracted a significant amount of attention from the materials science community. Nanoparticles with diameters in the range of 1 nm to 20 nm exhibit unique physical properties that give rise to many potential applications. Two fundamental factors are crucial as regards the novel properties of semiconductor nanoparticles. The first is the large surface-to-volume ratio. In this regard, the surface states are likely to trap electrons and/or holes, and induce a nonradiative recombination of these charge carriers, leading to a reduction in the luminescent and photovoltaic efficiency. The second approach takes advantage of the surface-plasmon resonance from metal nanostructures to semiconductors. The interactions between the semiconductor nanoparticles and the surface plasmons generate enhanced emission by electromagnetic-field amplification, and also causes the suppression of the emission by the energy transfer between the semiconductor and the metal nanoparticles. Therefore, surface passivation and surface plasmon in semiconductor nanoparticles with controlled nanostructures are important when attempting to improve both the luminescent and photovoltaic efficiency.