Properties Of Carbon Nanostructures Prepared By Polyaniline Carbonization

Nanometric sponge-like structures have been prepared from the carburization of polyaniline-(emeradine salt) using a rapid immersion in hot-filament system fed with carbon dioxide, ethyl alcohol and argon. Fiber-like fragments of width in the range of 20 - 40 nm have been observed by field emission scanning electron microscopy (FESEM). Raman measurements suggested that benzenoid rings and amide were present in the carburized samples. Lowest threshold achieved for field emission was 23.5 V/μm. © 2007 IOP Publishing Ltd.6117174Bonard, J.M., Kind, H., Stöckli, T., Nilsson, L.O., (2001) Sol. State Electron., 45 (6), p. 893Journet, C., Bernier, P., (1998) Appl. Phys., 67 (1), p. 1Morell, G., Gonzlez-Berríos, A., Weiner, B.R., Gupta, S., (2006) J. Mater. Sci: Mater. Electron, 17 (6), p. 443Koeck, F.A.M., Zumer, M., Nemanic, V., Nemanich, R.J., (2006) Diam. Rel. Mater., 15 (4-8), p. 880Andreatta, A., Cao, Y., Chiang, J.C., Heger, A.J., (1988) Synth. Met., 26 (4), p. 383Konyushenko, E.N., Stejskal, J., Trchov, M., Hradil, J., Kovrov, J., Prokes, J., Cieslar, M., Sapurina, I., (2006) PolymerNastase, C., Nastase, F., Vaseashta, A., Stamatin, I., (2006) Prog. Sol. Sta. Chem., 34 (2-4), p. 181Mottaghittalab, V.B., Spinks, G.M., Wallace, G.G., (2006) Synth. Met.Nickels, P., Dittimer, W.U., Beyer, S., Kottahous, J.P., Simmel, F.C., (2004) Nanotech., 15 (11), p. 1524Zhang, M.Y., Kaner, R.B., (2004) J. Am. Chem. Soc., 126 (22), p. 7097Baibarac, M., Baltog, I., Lefrand, S., Mevellec, J.Y., Chauvet, O., (2003) Chem. Mater., 15 (21), p. 4149Quillard, S., Loaurn, G., Lefrant, S., MacDiamird, A.G., (1994) Phys. Rev., 50 (17), p. 12496Mammana, V.P., Santos, T.E.A., Mammana, A., Baranauskas, V., Ceragioli, H.J., Peterlevitz, A.C., (2002) Appl. Phys. Lett., 81 (18), p. 3470Baranauskas, V., Fontana, M., Ceragioli, H.J., Peterlevitz, A.C., (2004) Nanotech., 15 (10), p. 678Kurt Bonard, R.J.M., Karimi, A., (2001) Diam.Rel. Mater., 10 (11), p. 1962Gupta Weiner, S.B.R., Morell, G., (2002) Diam. Rel. Mater., 11 (3-6), p. 799Wu, K., Wang, E.G., Cao, Z.X., Wang, Z.L., Jiang, X., (2000) J. Appl. Phys., 88 (5), p. 2967Proffitt, S.S., Probert, S.J., Whitfield, M.D., Foord, J.S., Jackman, R.B., (1999) Diam. Rel. Mater., 8 (2-5), p. 76

Field-emission Properties Of Sulphur Doped Nanocrystalline Diamonds

Nanostructured diamond doped with sulphur has been prepared using a hot-filament assisted chemical vapour deposition system fed with an ethyl alcohol, carbon disulfide, hydrogen, and argon mixture. The reduction of diamond grains to the nanoscale is relevant to create a network of defective grain boundaries which may be n-type doped to facilitate the transport and injection of electrons to the diamond grains located at the vacuum interface, enhancing the electron field-emission properties of the samples. The downsizing was produced by secondary nucleation and defects induced by sulphur and argon atoms in the chemical vapour deposition surface reactions. Sulphur also acts as an n-type dopant of diamond. Raman measurements show that the samples are nanodiamonds embedded in a matrix of graphite and disordered carbon grains and the morphology, revealed by field electron scanning microscopy, shows that the grains are in the range of 10 to 30 nm. The lowest threshold achieved for field emission was 13.20 V/μm. © 2007 IOP Publishing Ltd.6116670Yang, A.T.S., Lay, J.Y., Wong, M.S., Cheng, C.L., (2002) J. Appl. Phys., 92 (4), p. 2133Mammana, V.P., Tea, S., Mammana, A., Baranauskas, V., Ceragioli, H.J., Peterlevitz, A.C., (2002) Appl. Phys. Lett., 81 (18), p. 3470Baranauskas, V., Fontana, M., Ceragioli, H.J., Peterlevitz, A.C., (2004) Nanotech., 15 (10), p. 678Gruen, D.M., (1998) MRS Bull., 9, p. 32Jin, B.M., Kim, C.C., (1997) Appl. Phys. A: Solid Surf., 65 (1), p. 53Himpsel, F.J., Knapp, J.A., Vanvechten, J.A., Eastman, P.E., (1979) Phys. Rev., 20 (2), p. 624Bandis, B., Pate, B.B., (1996) Appl. Phys Lett., 69 (3), p. 366Okano, K., Yamada, T., Suave, A., Koizumi, S., Pate, B.B., (1999) Appl. Surf. Sci., 146 (1-4), p. 274Kurt Bonard, R.J.M., Karimi, A., (2001) Diam. Rel. Mater., 10 (11), p. 1962Bonnot, A.M., Deldem, M., Beaugnon, M., Fournier T.schouler, M.C., Mermoux, M., (1999) Diam. Rel. Mater., 8 (2-5), p. 631Gruen, D.M., Liu, S., Krauss, A.R., Liuy, A., Luo, J., Foster, C.M., (1994) J. Vac. Sci. Technol., 12 (4), p. 1491Gupta Weiner, S.B.R., Morell, G., (2002) Diam. Rel. Mater., 11 (3-6), p. 799Gupta Weiner, S.B.R., Morell, G., (2005) J. Appl. Phys., 97, p. 094307Morell, G., Gonzlez-Berríos, A., Weiner, B.R., Gupta, S., (2006) J. Mater. Sci: Mater. Electron, 17 (6), p. 443Koeck, F.A.M., Zumer, M., Nemanic, V., Nemanich, R.J., (2006) Diam. Rel. Mater., 15 (4-8), p. 880Shroder Nemanich, R.E.R.J., Glass, J.T., (1990) Phys. Rev., 41 (6), p. 3738Birrell, J., Gerbi, J.E., Auciello, O., Gibson, J.M., Johnson, J., Carlisle, J.A., (2005) Diam. Rel. Mater., 14 (1), p. 86Ferrari, A.C., Robertson, J., (2001) Phys. Rev., 63, pp. 121405RWu, K., Wang, E.G., Cao, Z.X., Wang, Z.L., Jiang, X., (2000) J. Appl. Phys., 88 (5), p. 2967Proffitt, S.S., Probert, S.J., Whitfield, M.D., Foord, J.S., Jackman, R.B., (1999) Diam. Rel. Mater., 8 (2-5), p. 76

Synthesis And Characterization Of Boron-doped Carbon Nanotubes

Boron-doped carbon nanotubes have been prepared by chemical vapour deposition of ethyl alcohol doped with B2O3 using a hot-filament system. Multi-wall carbon nanotubes of diameters in the range of 30 - 100 nm have been observed by field emission scanning electron microscopy (FESEM). Raman measurements indicated that the degree of C-C sp2 order decreased with boron doping. Lowest threshold fields achieved were 1.0 V/μm and 2.1 V/μm for undoped and boron-doped samples, respectively. © 2008 IOP Publishing Ltd.100PART 5Bonard, J.M., Kind, H., Stöckli, T., Nilsson, L.O., (2001) Sol. State Electron., 45, p. 893Maultzsch, J., Reich, S., Thomsen, C., Webster, S., Czerw, R., Carroll, D.L., Vieira, S.M.C., Rego, C.A., (2002) Appl.Phys.Lett., 81, p. 2647Mondal, K.C., Coville, N.J., Witcomb, M.J., Tejral, G., Havel, J., (2007) Chem. Phys. Lett., , in pressChen, C.F.C., Tsai, C.L., Lin, C.L., (2003) Diam. Rel. Mater., 12, p. 1500Sharma, R.B., Late Joag, D.S., Govindaraj Rao, C.N.R., (2006) Chem.Phys.Lett, 428, p. 102Mennella, V., Monaco, G., Colanoeli, L., Bussoletti, E., (1995) Carbon, 33 (2), p. 11

Fabrication Of Tubes Of Diamond With Micrometric Diameters And Their Characterization

The fabrication and characterization of 'self-supporting' diamond tubes grown by chemical vapor deposition (CVD) are reported. Diamond layers were deposited onto tungsten wires with diameters of 238 μm; the tungsten cores were subsequently completely removed by etching to leave 'self-supporting' diamond tubes with a diameter of approximately 400 μm and length of 20 mm. A hot-filament CVD system fed with ethanol highly diluted in hydrogen was employed. Growth rates of 7.8 μm h-1 have been measured and incubation times >3 h have been estimated. Scanning electron microscopy of cross-sections revealed columnar structures, which terminate on sharp (111) facets on the tube's external surface. Raman spectroscopy showed that the tube structure is predominantly composed of C-C sp3 bonds, with intrinsic tensile stresses. © 2002 Elsevier Science B.V. All rights reserved.420-421151154Angus, J.C., Hayman, C.C., (1988) Science, 241, p. 913Yarborough, W.A., Messier, R., (1990) Science, 241, p. 688Corat, E.J., Trava-Airoldi, V.J., Baranauskas, V., (1998) Key Eng. Mater., 138 (1), p. 195Morrish, A.A., Glesener, J.W., Fehrenbacher, M., Person, P.E., Maruyama, B., Natishan, P.M., (1994) Diamond Relat. Mater., 3, p. 173May, P.W., Rego, C.A., Thomas, R.M., Ashfold, M.N.R., Rosser, K.N., Everitt, N.M., (1994) Diamond Relat. Mater., 3, p. 810Baranauskas, V., Ceragioli, H.J., Peterlevitz, A.C., Durrant, S.F., (2001) Thin Solid Films, 398, p. 250Baranauskas, V., Peled, A., Trava-Airoldi, V.J., Lima, C.A.S., Doi, I., Corat, E.J., (1994) Appl. Surf. Sci., 79-80, p. 129Barros, R.C.M., Corat, E.J., Ferreira, N.G., Souza, T.M., Trava-Airoldi, V.J., Leite, N.F., Iha, K., (1996) Diamond Relat. Mater., 5, p. 1323Whitfield, M.D., Savage, J.A., Jackman, R.B., (2000) Diamond Relat. Mater., 9, p. 262Zhu, W., McCune, R.R., DeVries, J.E., Tamor, M.A., Simon Ng, K.Y., (1995) Diamond Relat. Mater., 4, p. 220Shi, C.R., Avyigal, Y., Dirnfeld, S., Hoffman, A., Fayer, A., Kalish, R., (1995) Diamond Relat. Mater., 4, p. 1079Stoner, B.R., Ma, G.H.M., Wolter, S.D., Glass, J.T., (1992) Phys. Rev. B, 45, p. 11067Trava-Airoldi, V.J., Corat, E.J., Pena, A.F., Leite, N.F., Valera, M.C., Freitas, J.R., Baranauskas, V., (1996) Rev. Sci. Instrum., 67 (5), p. 1993Trava-Airoldi, V.J., Corat, E.J., Penã, A.F.V., Leite, N.F., Baranauskas, V., (1995) Diamond Relat. Mater., 4 (11), p. 125

A Study Of Thin Al Films On Sn

Thin films of Al thermally deposited on an Sn substrate were studied by means of Auger spectroscopy. The observation of the 66 and 1389 eV Al Auger electrons whose surface sensitivities are quite different gave insight into the morphology of the Al films. All intensities were normalized to their corresponding bulk yields from Al and Sn. The ratio of Al 66 to Al 1389 normalized intensities was found to be constant at 0.43 ± 0.04 even though the normalized Al 1389 intensity varied from 0.05 to 0.95. These results are consistent with the growth of a film composed of islands of Al whose exposed surface is enriched in Sn through a diffusion process. Independent determinations of the rate of adsorption of O2 by these films are consistent with this model. © 1993.22801/02/15162164Chadwick, Christie, Karolewski, (1981) Vacuum, 31, p. 705Roberts, Dobson, (1986) Thin Solid Films, 135, p. 137Peeters, Slavin, (1989) Surf. Sci., 214, p. 85Stucki, Erbudak, Kostorz, (1987) Appl. Surf. Sci., 27, pp. 393-40

Growth Of Glassy Carbon On Natural Fibers

Diamond-like carbon films were grown on pyrolised bamboo substrates by hot filament-chemical vapor deposition from ethanol/hydrogen mixtures. Different stages of deposition of films grown on untreated substrates and substrates seeded with diamond dust were compared. Changes in film morphology and structure under changes in these parameters were investigated using scanning electron microscopy and Raman spectroscopy. Diamond-like carbon (DLC) with ball-like morphology on the micrometer scale and glassy DLC with a stacked planar structure were observed for depositions of > 2 h on unseeded and seeded substrates, respectively. Gasification of the fibers by hydrogen in the early stages of growth may play a role in film growth, but this requires further study. Nevertheless, DLC films can be grown on pyrolised bamboo substrates, which suggests that other carbonaceous substrates for film fabrication by hot-filament chemical vapor deposition also merit systematic investigation. © 2002 Elsevier Science B.V. All rights reserved.3041-3271277Kojima, A., Matsumoto, H., Kamiishi, Y., Sato, M., Otani, S., (2000) Sen-I Gakkaishi, 56 (2), p. 574Bessette, R.R., Medeiros, M.G., Patrissi, C.J., Deschenes, C.M., LaFrata, C.N., (2001) J. Power Sources, 96 (1), p. 240Sea, B.K., Choo, S.Y., Lee, T.J., Morooka, S., Song, S.K., (1995) Kor. J. Chem. Eng., 12 (4), p. 416Edie, D.D., (1998) Carbon, 36 (4), p. 345Takida, T., Inoue, K., Kimura, H., Kiyota, H., Saito, I., Kurusu, T., Iida, M., (2000) New Diamond Frontier Carbon Res., 10 (1), p. 50Wang, Y.Q., Zhou, B.L., Wang, Z.M., (1995) Carbon, 33 (4), p. 427Peherson, P.E., Glesener, J., Morrish, A., (1992) Thin Solid Films, 212 (1-2), p. 81Nakamura, Y., Tamaki, K., Watanabe, Y., Hirayama, S., (1994) J. Mater. Res., 9 (7), p. 1619Gruen, D.M., (1999) Annu. Rev. Mater. Sci., 29, p. 211Corat, E.J., Trava-Airoldi, V.J., Baranauskas, V., (1998) Key Eng. Mat., 138 (1), p. 195Baranauskas, V., Tosin, M.C., Peterlevitz, A.C., Ceragioli, H.J., Durrant, S.F., (2000) J. Appl. Phys., 88 (3), p. 1650Barros, R.C.M., Corat, E.J., Ferreira, N.G., Souza, T.M., Trava-Airoldi, V.J., Leite, N.F., Iha, K., (1996) Diam. Rel. Mater., 5, p. 1323Baranauskas, V., Peterlevitz, A.C., Ceragioli, H.J., Durrant, S.F., (2001) J. Vac. Sci. Tech. A, 19 (4), p. 1057Thareja, R.K., Dwivedi, R.K., Abhilasha, (1997) Phys. Rev. B, 55 (4), p. 2600Nemanich, R.J., Solin, S.A., (1979) Phys. Rev. B, 20, p. 392Yoshikawa, M., Katagiri, G., Ishida, H., Ishitani, A., Ono, M., Matsumura, K., (1989) Appl. Phys. Lett., 55, p. 2608Ferrari, A.C., Robertson, J., (2001) Phys. Rev. B, 63, p. 63Shroder, R.E., Nemanich, R.J., Glass, J.T., (1990) Phys. Rev. B, 41, p. 3738Okada, K., Kanda, H., Komatsu, S., Matsumoto, S., (2000) J. Appl. Phys, 88, p. 1674Suzuki, T., Yagi, M., Shibuki, K., Hasemi, M., (1994) Appl. Phys. Lett., 65 (5), p. 540Li, Z.D., Wang, L., Suzuki, T., Argoitia, A., Pirouz, P., Angus, J.C., (1993) J. Appl. Phys., 73 (2), p. 715Lambrecht, W.R.L., Lee, C.H., Segall, B., Angus, J.C., Li, Z.D., Sunkara, M., (1993) Nature, 364 (6438), p. 60

Deposition Of Diamond And Diamond-like Carbon Nuclei By Electrolysis Of Alcohol Solutions

We show that nuclei and aggregates of diamond, diamond-like carbon (DLC) and crystalline graphite may be deposited by the electrolysis of heated methanol. The structures were characterized by micro-Raman spectroscopy, optical microscopy and scanning electron microscopy (SEM). It is observed that bubble formation inhibits the film deposition in DLC form on the immersed substrate but enhances the formation of carbon nuclei on the wetted capillary area of the substrate. We observed experimentally an inhomogeneity in the film thickness in the vertical direction and explain this effect by relating it to an inhomogeneous turbulent 'boiling layer' present near the cathode. In addition, we observed that the film growth rate on the wetted capillary area is much higher than the average growth rate on the immersed cathode. © 1999 Elsevier Science B.V. All rights reserved.144-1450260264Trava-Airoldi, V.J., Corat, E.J., Baranauskas, V., (1997) Advanced Ceramic Tools for Machining Applications - III, 138-140, p. 195. , I.M. Low (Ed.), Trans-Tech, SwitzerlandNamba, Y., (1992) J. Vac. Sci. Technol. A, 10 (5), p. 3368Wang, H., Shen, M., Ning, Z., Ye, C., Cao, C., Dang, H., Zhu, H., (1996) Appl. Phys. Lett., 69 (8), p. 1074Novikov, V.P., Dymont, V.P., (1997) Appl. Phys. Lett., 70 (2), p. 200Nemanich, R.J., Solin, S.A., (1979) Phys. Rev. B, 20, p. 392Yoshikawa, M., Katagiri, G., Ishida, H., Ishitani, A., Ono, M., Matsumura, K., (1989) Appl. Phys. Lett., 55, p. 2608Knight, D.S., White, W.B., (1989) J. Mater. Res., 4 (2), p. 385Tuinstra, F., Koenig, J.L., (1970) J. Chem. Phys., 53, p. 1126Landau, L.D., Lifshitz, E.M., (1980) Statistical Physics, 5 (PART 1), p. 535. , Pergamon, Oxfor