The electronic and ¯eld emission properties of the fullerene end-functionalized zinc oxide nanotube (ZnONT) are investigated by density functional theory (DFT) to search for novel ¯eld emitter nano material. The interaction energies of ZnONT/fullerenes complexes gradually increase, with increasing the nanotube lengths which indicate that ZnONTs with higher lengths could improve the stability of the complexes. The band gaps of connected construction of fullerene molecules with ZnONTs gradually reduced by increasing the tube length, but were not sensitive to the tubes diameter. It is found that the ionization potentials of ZnONT/fullerenes complexes mainly decrease compared to that of pristine nanotube in the presence of 0, 0.002, 0.004 a.u. electric ¯eld. The reduction of the ionization potential means the enhancement of the ¯eld emission properties of ZnONT/fullerenes complexes compared with simple ZnONT and fullerene molecules. The calculations show that the combination of ZnONT with fullerene molecules indeed improves the ¯eld emission by controlling the tube size and electric ¯eld strength.
