• 文献标题:   Heterogeneity in the fluorescence of graphene and graphene oxide quantum dots
  • 文献类型:   Article
  • 作  者:   BRADLEY SJ, KROON R, LAUFERSKY G, RODING M, GOREHAM RV, GSCHNEIDTNER T, SCHROEDER K, MOTHPOULSEN K, ANDERSSON M, NANN T
  • 作者关键词:   graphene quantum dot, quantum yield, fluorescence lifetime, photoluminescence, characterization, tem, nmr, raman spectroscopy
  • 出版物名称:   MICROCHIMICA ACTA
  • ISSN:   0026-3672 EI 1436-5073
  • 通讯作者地址:   Victoria Univ Wellington
  • 被引频次:   17
  • DOI:   10.1007/s00604-017-2075-9
  • 出版年:   2017

▎ 摘  要

Heterogeneity is an inherent property of a wealth of real-world nanomaterials and yet rarely in the reporting of new properties is its effect sufficiently addressed. Graphene quantum dots (GQDs) - fluorescent, nanoscale fragments of graphene - are an extreme example of a heterogeneous nanomaterial. Here, top-down approaches - by far the most predominant - produce batches of particles with a distribution of sizes, shapes, extent of oxidation, chemical impurities and more. This makes characterization of these materials using bulk techniques particularly complex and comparisons of properties across different synthetic methods uninformative. In particular, it hinders the understanding of the structural origin of their fluorescence properties. We present a simple synthetic method, which produces graphene quantum dots with very low oxygen content that can be suspended in organic solvents, suggesting a very pristine material. We use this material to illustrate the limitations of interpreting complex data sets generated by heterogeneous materials and we highlight how misleading this "pristine" interpretation is by comparison with graphene oxide quantum dots synthesized using an established protocol. In addition, we report on the solvatochromic properties of these particles, discuss common characterization techniques and their limitations in attributing properties to heterogeneous materials.