A high pressure, high temperature, scanning tunneling microscope for in situ studies of catalysts

We describe the construction and operation of a novel scanning tunneling microscope, which is capable of operating throughout a wide range of pressures (atmospheric—60 bar) and temperatures (300–650 K). The instrument has cylindrical symmetry and is constructed out of materials with low thermal conductivity and low coefficients of thermal expansion that allows imaging the same area over a wide temperature range. With this microscope we present images of the oxidation of polycrystalline nickel.