Energetic and electronic properties of hydrogen passivated ZnO nanowires

We investigated the hydrogen passivation to zinc oxide (ZnO) nanowires. The relaxations of the nanowires are different. We found the zinc ions with dangling bonds are more likely to hybridize than the oxygen ions. When all of the surface oxygen atoms are passivated, the surface zinc ions relax towards the neighboring surface zinc and try to hybridize each other. This behavior introduces new bands into the gap which change the electronic properties. On the other hand, band gap is increased when hydrogen atoms passivate zinc ions. The wire with all the surface ions passivated by hydrogen is energetically the most stable one.