The role of fluid-wall interactions on confined liquid diffusion using Mori theory

Analysis on the energetics, magnetism and electronic properties in a 45° ZnO grain boundary doped with Gd

The structural stability and magnetic properties of a grain boundary (GB) formed by aligning two ZnO single crystals oriented at an angle of 45° is investigated by density functional theory, using generalized gradient approximation (GGA) and taking the U parameter into consideration for the 4f impurity states. We found that the GB is stable with no dangling bonds and inter-granular structures. The stability of defects such as Gd substituted to the Zn site (Gd_Zn), Zn vacancy (V_Zn) and O vacancy (V_O) as well as defect complexes Gd_Zn–Gd_Zn, Gd_Zn–V_Zn, and Gd_Zn–V_O are analyzed using formation energy calculations. It is found that Gd_Zn–Gd_Zn clusters prefers to form at the GB. The spin polarization at the Gd_Zn sites is too localized and the exchange coupling energy is insufficient to overcome the thermal fluctuations. However, we show that the presence of V_Zn increases the hybridization between p orbitals of O as well as d orbitals of Zn, which can assist in increasing the magnetic polarization of the system. This work advances the understanding of the ferromagnetism in Gd-doped ZnO, indicating that Gd clustering at the GB is not likely to contribute to the ferromagnetism.

The structural stability and magnetic properties of a grain boundary (GB) formed by two ZnO single crystals oriented at 45° is investigated by density functional theory, using generalized gradient approximation (GGA) with Hubbard parameter (U).

Carbon nanotubes: a novel material for multifaceted applications in human healthcare

Remarkable advances achieved in modern material technology, especially in device fabrication, have facilitated diverse materials to expand the list of their application fields.