A thermoelectric power generation device using molybdenum metallization to a Zintl thermoelectric material in a thermoelectric power generation device operating at high temperature, e.g. at or above 1000° C., is disclosed. The Zintl thermoelectric material may comprise Yb14MnSb11. A thin molybdenum metallization layer of approximately 5 microns or less may be employed. The thin molybdenum layer may be applied in a foil under high pressure, e.g. 1800 psi, at high temperature, e.g. 1000° C. The metallization layer may then be bonded or brazed to other components, such as heat collectors or current carrying electrodes, of the thermoelectric power generation device.