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The field-emission characteristics of zirconium carbide (ZrC) nanowire with an oxidized surface are studied. When the ZrC nanowire is processed to introduce an oxidized surface, its field-emission performance is improved significantly, exhibiting a high field-emission current and enhanced emission current stability with a fluctuation of 1.7% in a vacuum of 6 × 10−8 Pa. Furthermore, a reduced turn-on voltage of the ZrC nanowire after oxidation was observed in the field-emission measurement, which is attributed to a reduction of the work function of the ZrC nanowire after oxidation treatment. Density functional theory calculations have also been performed to validate the mechanisms responsible for the improvement of field-emission stability and reduction in the work function of the ZrC nanowire.

Adsorption of H2, 2H2, O2, and CO on ZrB2(0001) was investigated by using high-resolution electron energy loss spectroscopy. In hydrogen and oxygen adsorption, a strong loss peak appears in the specular spectra, showing the dissociative adsorption on the threefold hollow site. The vibrational frequency shifts toward higher energy with increase in oxygen coverage, while little changes in vibrational frequencies were observed in the hydrogen or deuterium adsorption. This means that the interaction between the adsorbates is stronger in oxygen adsorption than in hydrogen adsorption. The initial stage of CO adsorption shows two vibrational peaks, one of which corresponds to the atomic oxygen described above, the other is therefore the atomic carbon, showing dissociative adsorption.