O2 dissociation on the side wall of aluminum nitride nanotube: a DFT investigation

Abstract

The probabilities of the singlet and triplet O2 dissociation on single-walled aluminum nitride nanotube (AlNNT) were explored here. The results suggest that the dissociation of singlet and triplet O2 on AlNNT go through intermediates on their pathways. Triplet O2 was found to be difficult to dissociate on (8, 0) AlNNT following the triplet dissociation pathways due to the high overall dissociation barriers that are greater than 1.48eV. The singlet O2 can dissociate on the nanotube following the singlet dissociation pathways with a lower dissociation barrier of 0.74eV. The effect of temperature was also considered and the results at room temperature indicated the unfavorable triplet dissociation barriers remained higher than 1.35eV. In contrast, a higher temperature helps facilitate the singlet pathway dissociation barrier to be decreased to 0.65eV at 298.15K. However, the overall dissociation of the triplet O2 on (8, 0) AlNNT decreases to 0.95eV at 0K and 0.86eV at 298.15K due to the spin–orbital coupling. With the decreasing of the overall dissociation barriers with increasing diameter of the nanotube, it can be further addressed that both singlet and triplet O2 can dissociate on AlNNT but more strict condition is needed for triplet O2 dissociation such as AlNNT with large diameter or high temperature. Moreover, the electronic structure of AlNNT would be modified and its conductivity increases when interacting with O2. The results presented here will be a guide for application of AlNNT in nanodevices such as detecting O2 and spintronics applications.