Maia Francisco C B, Samad Ricardo E, Bettini Jefferson, Freitas Raul O, Vieira Junior Nilson D, Souza-Neto Narcizo M
Laboratório Nacional de Luz Síncrotron (LNLS), Campinas, São Paulo 13083-970, Brazil.
Instituto de Pesquisas Energéticas e Nucleares (IPEN-CNEN/SP), São Paulo 05508-000, Brazil.
Sci Rep. 2015 Jul 7;5:11812. doi: 10.1038/srep11812.
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.
超短激光脉冲引起的环境能量快速变化已在碳同素异形体中诱导了相变,因此有望揭示新的碳相。在此,通过在标准大气环境下将多晶石墨暴露于能量密度为4 J/cm²的25飞秒激光脉冲下,我们展示了携带类金刚石相和洋葱状碳相的半透明微米级结构的合成。还识别出了金刚石相的纹理化区域。关于不同合成碳形式、脉冲叠加以及热力学过程的奇点,我们确定了合成机制,即激光诱导的后续产物通过能量演化达到类金刚石相。