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Zinc oxide nanorods (ZnO NRs) have gained considerable research interest due to their robust energy conversion efficiency. In the present work, ZnO NRs arrays were pinpointed to probe their electromechanical response under strain conditions. ZnO seed was sputtered on different substrates by radio frequency magnetron sputtering (RF) technique at 80 W constant power and 3.49 × 10−5 mbar base pressure. The X-ray diffraction patterns exhibit hexagonal wurtzite structure with preferred c-axis crystal directions in the (002) plane. The average thickness of the seed layer for all the samples was estimated at around 214.6 nm. Surface roughness and morphologies of the nanorods have been characterized by atomic force microscopy (AFM) and field emission scanning electron microscopy (FESEM), respectively. FE-SEM images show homogeneous growth in different directions on substrates. The average diameters of ZnO NRs on silicon, glass and ITO were 51, 58 and 61 nm, respectively. The average length of all the nanorods on the substrates were measured around 1–2 μm. The local piezoresponse measurements conducted on two selected domain regions of the nanorod arrays had been characterized by piezoresponse force microscopy (PFM) to confirm the switching-piezoelectric behavior.

Indium antimonide nanowires were synthesized by electrochemical deposition using anodic aluminum oxide template in the presence of gold film as conductive layers. Field emission scanning electron microscopy and energy dispersive X-ray spectrometry measurements were carried out to investigate the effect of adhesive insulated tape covered below the conductive layer. Results showed that the anodic aluminum oxide template covered with insulating tapes had better morphology with less presence of overgrown rough film on the topside of the anodic aluminum oxide template and it exhibited a smoother nanowire sidewall as compared to the uncovered ones. Additionally, the unique properties of anodic aluminum oxide were controllable pore diameter with a narrow size distribution at some intervals. It was evident from the energy dispersive X-ray spectrum that the nanowires synthesized from the covered template condition exhibited better InSb composition and stoichiometric ratio compared to the uncovered template condition.

We report our investigation on the growth of ZnO nanostructure on a patterned interdigitated microelectrode (IDE) using chemical bath deposition (CBD). Piezoresponse force microscopic techniques were used to characterise the piezoelectric material domain of the grown ZnO nanostructures. The synthesised ZnO nanostructures exhibits a hexagonal wurtzite structure with the c-axis preferred crystal orientation in the (002) plane. The average thickness of the ZnO seed layer was 467.5 nm, whereas the diameter and length of ZnO nanostructure were measured to be 2.73 µm and 6.96 µm respectively. The combine effect of Zinc nitrate and HTMA concentration and seed layer thickness are considered as the main reason for crystal morphology evolution. The ZnO nanostructures exhibited a phase switch of the response and hysteresis in the plot of phase versus dc voltage, as evidenced by the polarization exchanging of its ferroelectric behaviour. These results provide a fundamental understanding of piezoresponse ZnO nanostructure for future energy applications.

In this paper, we have investigated stable structural, electric and magnetic properties of manganese (Mn) atom adsorption on armchair hydrogen edge-terminated boron nitride nanoribbon (A-BNNRs) using first principles method based on density-functional theory with the generalized gradient approximation. Calculation shows that Mn atom situated on the ribbons of A-BNNRs is the most stable configuration, where the bonding is more pronounced. The projected density of states (PDOS) of the favored configuration has also been computed. It has been found that the covalent bonding of boron (B), nitrogen (N) and Mn is mainly contributed by s, d like-orbitals of Mn and partially occupied by the 2p like-orbital of N. The difference in energy between the inner and the edge adsorption sites of A-BNNRs shows that Mn atoms prefer to concentrate at the edge sites. The electronic structures of the various configurations are wide, narrow-gap semiconducting and half-metallic, and the magnetic moment of Mn atoms are well preserved in all considered configurations. This has shown that the boron nitride (BN) sheet covered with Mn atoms demonstrates additional information on its usefulness in future spintronics, molecular magnet and nanoelectronics devices.

In this study, the adsorption influence of two different metals, gallium (Ga) and arsenide (As) adatoms on the stabilities and electronic structure of single graphene layer has been systematically studied using first-principles pseudopotentials calculations within the framework of density functional theory (DFT). The generalized gradient approximation used is PW91 exchange-correlation functional. The results of our calculations reveal that the adsorption of Ga atom on graphene resulted in electron transfer mainly from p-orbital of the Ga adatom to graphene and subsequently, altered the electronic state of graphene by shifting the Fermi level away from Dirac point, up to ∼1.5 eV. Meanwhile, the d-orbitals of Ga adatom have spin polarization at the Fermi level where the minority spin d-orbitals are unoccupied. The As adatom was found to have larger adsorption energy value on H, B and T sites of graphene compared to Ga adatom. Thus, we described this energy difference as a result of the bonding configurations between both Ga and As atoms with carbon in the graphene structure. While B-site favored the adsorption of arsenic adatom, we found that the most favored adsorption site for Ga adatom on graphene is above H-sites.

Stable geometries, electronic and magnetic properties of low coverage vanadium (V) atoms adsorption on graphene sheet have been investigated by first principles calculations, using generalized gradient approximation. Calculation shows that center of the ring is energetically favorable for both V adatom and perpendicular dimer after relaxation. Moreover, the proportion of orbital contribution of C-V bonding are mainly dominated by 2pz orbital of C and partially occupied by the 3d like states of V. It is also found that the low coverage V atom adsorbed graphene system is metallic and magnetic, and has demonstrated additional hint on its usefulness in magnetic devices.