• 文献标题:   Synthesis of bilayer graphene nanosheets by pulsed laser ablation in liquid and observation of its tunable nonlinearity
  • 文献类型:   Article
  • 作  者:   PRAMANIK A, KARMAKAR S, KUMBHAKAR P, BISWAS S, SARKAR R, KUMBHAKAR P
  • 作者关键词:   laser ablation, waste material, graphene nanosheet, optical propertie, spatial selfphase modulation, nonlinear optical propertie
  • 出版物名称:   APPLIED SURFACE SCIENCE
  • ISSN:   0169-4332 EI 1873-5584
  • 通讯作者地址:   Natl Inst Technol
  • 被引频次:   1
  • DOI:   10.1016/j.apsusc.2019.143902
  • 出版年:   2020

▎ 摘  要

Bilayer graphene nanosheets (B-GNSs) have been synthesized from dry-cell graphite electrode by using facile laser ablation in liquid technique in ambient condition. The plasma plume generated on incidence of ns pulsed Nd: YAG laser fundamental radiation of 1064 nm has facilitated the transformation of bulk graphite (BG) into B-GNSs via liquid carbon phase within 30 min of laser irradiation, and the layer number is are found to be increased with further increase in laser ablation time. The thickness dependent coherent nonlinear optical (NLO) response of the synthesized materials in aqueous dispersion has been determined by spatial self-phase modulation technique. The oxygen-containing surface defects in multilayer GNSs (M-GNSs) have led to scarcity in amount of e-h pairs in compared to that in B-GNSs. Therefore, a better NLO polarization has been observed in BGNSs in compared to that of M-GNSs. Moreover, the thickness dependent thermal conductivity and hydrodynamic performance of GNSs-water dispersion has led to the observation of tunable NLO response with change in temperature as well as with the intensity of pump laser. The experimental findings obtained in this work may be considered as a key step towards fabrication of graphene from graphitic waste materials for development of future nonlinear photonics devices.