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Synthesis of diamond-like phase from graphite by ultrafast laser driven dynamical compression.

ABSTRACT: Rapid variations of the environmental energy caused by ultrashort laser pulses have induced phase transitions in carbon allotropes, therefore bringing the promise of revealing new carbon phases. Here, by exposing polycrystalline graphite to 25 fs laser pulses at 4 J/cm(2) fluence under standard air atmosphere, we demonstrated the synthesis of translucent micrometer-sized structures carrying diamond-like and onion-like carbon phases. Texturized domains of the diamond phase were also identified. Concerning different synthesized carbon forms, pulse superposition and singularities of the thermodynamical process, we pinpoint the synthesis mechanism by the laser-induced subsequent products energetically evolving to attain the diamond-like phase.

SUBMITTER: Maia FC

PROVIDER: S-EPMC4493556 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Synthesis of diamond-like phase from graphite by ultrafast laser driven dynamical compression.

Maia Francisco C B FC Samad Ricardo E RE Bettini Jefferson J Freitas Raul O RO Vieira Junior Nilson D ND Souza-Neto Narcizo M NM

Scientific reports 20150707

Rapid variations of the environmental energy caused by ultrashort laser pulses have induced phase transitions in carbon allotropes, therefore bringing the promise of revealing new carbon phases. Here, by exposing polycrystalline graphite to 25 fs laser pulses at 4 J/cm(2) fluence under standard air atmosphere, we demonstrated the synthesis of translucent micrometer-sized structures carrying diamond-like and onion-like carbon phases. Texturized domains of the diamond phase were also identified. C ...[more]

PMID: 26149413

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