Programas de Investigación

URI permanente para esta comunidadhttps://repositorioinvestigare.pucmm.edu.do/handle/20.500.12060/2096

La PUCMM cuenta con seis (6) programas de investigación e innovación que responden a su misión de buscar soluciones científicas a los desafíos que enfrenta el pueblo dominicano y su e​ntorno global.

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Examinando Programas de Investigación por Materia "Nanocristal"

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  • Miniatura
    Ítem
    Low temperature, pressureless sp2 to sp3 transformation of ultrathin, crystalline carbon films
    (ELSEVIER) Piazza, Fabrice; Gough, Kathleen; Monthioux, Marc; Puech, Pascal; Gerber, Iann; Wiens, Richard; Paredes, Germercy; Ozoria, Cristhofer
    Nanosized and crystalline sp3-bonded carbon materials were prepared over large surface areas up to ~33x51 m2 from the exposure of few-layer graphene (FLG) to H radicals produced by the hot-filament process at low temperature (below 325 C) and pressure (50 Torr). Hybrid materials were also obtained from the partial conversion of FLG. sp3-C related peaks from diamond and/or lonsdaleite and/or hybrids of both were detected in UV and visible Raman spectra. C-H bonding was directly detected by Fourier Transform Infrared (FTIR) microscopy over an area of ~150 m2 and one single component attributed to sp3-C-H mode was detected in the C-H stretching band showing that carbon is bonded to one single hydrogen and strongly suggesting that the sp3-C materials obtained are ultrathin films with basal planes hydrogenated. The experimental results are compared to computational predictions and comprehensively discussed. Those materials constitute new synthetic carbon nanoforms after fullerenes, nanodiamonds, carbon nanotubes and graphene. This opens the door to new research in multiple areas for the development of new potential applications and may have wide scientific impact, including for the understanding of extraterrestrial diamond-related structures and polytype formation mechanism(s).
  • Miniatura
    Ítem
    Synthesis of diamond nanocrystals on polyimide film
    (ELSEVIER) Piazza, Fabrice; Solá, Francisco; Resto, Oscar; Fonseca, Luis F.; Morell, Gerardo
    Sulfur-assisted hot-filament chemical vapor deposition (HFCVD) was recently employed to grow diamond nano-crystals on polyimide film [F. Piazza, G. Morell, Diamond and Related Materials, 16 (2007) 1950], unambiguously showing that the substrate temperature was below 360 °C, the polyimide glass transition temperature. This accomplishment has opened the door to employ diamond in a wide range of applications where it needs to be integrated with temperature sensitive materials. The result reported earlier relies on visible Raman spectroscopy analysis. We hereby report new additional evidences confirming the result from transmission electron microscopy (TEM), high-resolution TEM, energy dispersive X-ray analysis, electron energy loss spectroscopy and selected area electron diffraction.