Applications of PEEM/LEEM in dynamic studies of surface physics and chemistry of two-dimensional atomic crystals

Abstract

Photoemission electron microscopy (PEEM)/low energy electron microscopy (LEEM) are surface techniques that can be used to image surface structure, electronic states, and surface chemistry. Important applications of the technique in catalysis, energy, nano science, and material sciences have been seen. In this paper, we briefly introduce the principle of PEEM/LEEM and the recent advances of the technique. Then, some applications of PEEM/LEEM in dynamic studies of surface physics and chemistry of two-dimensional (2D) atomic crystals are highlighted, which include the growth of 2D atomic crystals, the formation of 2D heterostructures, the intercalation of the 2D materials, and chemical reactions confined under the 2D materials. Using surface imaging, micro-region low energy electron diffraction (μ-LEED), and the intensity-voltage (I-V) curves, the kinetics of 2D material growth and reactions at the 2D material/solid interfaces can be deeply understood.