Surface and Volume Photoemission through Low-Barrier and Ohmic Interfaces in Metal Nanoparticles

We investigate the surface photoemission (SPE) and the volume (VPE) photoemission from metal nanoparticles into semiconductor environments with a varied height of the potential barrier at the metal-semiconductor interface. We show that the internal quantum efficiency of the SPE becomes several times larger than the one of the VPE, when the barrier height decreases and the contact on the interface approaches to the ohmic one. Discontinuities in the electron effective mass and in dielectric functions at the interface are taken into account in the calculations. Results are important for efficient generation of hot electrons from metal nanostructures for such applications as photocatalysis and water splitting.