@article { ISI:000271238900027, title = {Field emission properties of Al-doped ZnO nanostructures}, journal = {Journal of Nano Research}, volume = {5}, year = {2009}, month = {JAN}, pages = {231-237}, publisher = {TRANS TECH PUBLICATIONS LTD}, address = {LAUBISRUTISTR 24, STAFA-ZUERICH, CH-8712, SWITZERLAND}, abstract = {

Field emission from Al-doped ZnO nanostrcutures has been investigated in planar diode configuration under ultra high vacuum conditions. The Al-doped ZnO nanostructures were synthesized by co-precipitation method with varying aluminium concentrations. The as- synthesized product was characterized by x-ray diffraction, scanning electron microscope and energy dispersive x-ray analysis. The threshold field required to draw a current density of similar to 1 mu A/cm(2) was observed to be similar to 2.0 V/mu m and similar to 2.3 V/mu m for Al-doped ZnO nanostructures synthesized with aluminium concentrations of 1\% and 3\%, respectively. The Fowler- Nordheim (F-N) plots for both the specimens exhibit non-linear behaviour, which is observed to be specimen dependent. The nonlinearity observed in the F-N plots has been interpreted on the basis of the theory of electron emission from semiconductor emitters. The field enhancement factors, estimated from the slope of the F-N plots, are found to be similar to 9.3 x 10(3) and 3.9 x 10(3) for 1\% and 3\% Al-doped ZnO emitters, respectively. The high values of the field enhancement factor Suggest that the emission is from the nanostructures. The emission current stability measured at the preset value of similar to 2 mu A over a period of more than three hours is found to be fairly stable. The results indicate use of Al-doped ZnO nanostructures as promising emitters for field emission based devices.

}, keywords = {field emission, Fowler-Nordheim plots, Nanostructures, ZnO}, issn = {1662-5250}, author = {Navale, Shalaka C. and Sheini, Farid Jamali and Patil, Sandip S. and Mulla, Imtiaz S. and Joag, Dilip S. and More, Mahendra A. and Gosavi, Suresh W.} } @article { ISI:000283453700016, title = {Fowler-nordheim plot behavior and mechanism of field electron emission from ZnO tetrapod structures }, journal = {ACS Nano}, volume = {4}, number = {10}, year = {2010}, month = {OCT}, pages = {5585-5590}, publisher = {AMER CHEMICAL SOC}, address = {1155 16TH ST, NW, WASHINGTON, DC 20036 USA}, abstract = {

Field emission measurements of current-voltage characteristics are reported for tetrapod structures of ZnO. The nonlinear Fowler-Nordheim (FN) plot is analyzed according to a model of calculation based on saturation of conduction band current and predominance of valence band current at high-field values. The simulated FN plot exhibits similar features to those observed experimentally. The model of calculation suggests that the slope variation of the FN plot, in the high-field and low-field regions, does not depend on the magnitude of saturation. Instead, it is a characteristic of the energy band structure and voltage-to-barrier-field conversion factor of the emitting material.

}, keywords = {field emission, Fowler-Nordheim plot, Nanostructures, nonlinearity, ZnO}, issn = {1936-0851}, doi = {10.1021/nn1008403}, author = {Al-Tabbakh, Ahmed A. and More, Mahendra A. and Joag, Dilip S. and Mulla, Imtiaz S. and Pillai, Vijayamohanan K.} } @article { ISI:000344791100009, title = {Metallic few-layer flowerlike VS2 nanosheets as field emitters}, journal = {European Journal of Inorganic Chemistry}, number = {31}, year = {2014}, month = {NOV}, pages = {5331-5336}, publisher = {WILEY-V C H VERLAG GMBH}, address = {BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY}, abstract = {

We report first-principles DFT calculations of the single-layer VS2 work function, the experimental synthesis of flower-like few-layer-thick VS2 nanosheets by a simple one-step hydrothermal method, and the investigation of their field emission properties. The turn-on field required to draw emission current densities of 1 and 10 mu A/cm(2) were 4 and 5.01 V/mu m, respectively. The observed turn-on field values are attributed to the high field enhancement factor (ca. 2500), which is due to presence of sharp protrusions in the VS2 nanosheets. Furthermore, the field-emission current stability of the VS2 emitter shows stable behavior over a period of 12 h. Further, DFT calculations show that the work function (f) of the single-layer VS2 emitter is 6.01 eV.

}, keywords = {Density functional calculations, field emission, Layered compounds, Nanostructures, Sulfur, Vanadium}, issn = {1434-1948}, doi = {10.1002/ejic.201402448}, author = {Rout, Chandra Sekhar and Khare, Ruchita T. and Kashid, Ranjit V. and Joag, Dilip S. and More, Mahendra A. and Lanzillo, Nicholas A. and Washington, Morris and Nayak, Saroj K. and Late, Dattatray J.} }