Nanosheet

Source: Wikipedia, the free encyclopedia.

A nanosheet is a two-dimensional nanostructure with thickness in a scale ranging from 1 to 100 nm.[1][2][3]

A typical example of a nanosheet is graphene, the thinnest two-dimensional material (0.34 nm) in the world.[4] It consists of a single layer of carbon atoms with hexagonal lattices.

Examples and applications

As of 2017, silicon nanosheets were being used to prototype future generations of small (5 nm) transistors.[5]

Carbon nanosheets (from hemp) may be an alternative to graphene as electrodes in supercapacitors.[6]

Synthesis

3D AFM topography image of multilayered palladium nanosheet on silicon wafer.[7]

The most commonly used nanosheet synthesis methods use a bottom-up approach, e.g., pre-organization and polymerization at interfaces like

coarse-grained model with parameters from semi-empirical quantum mechanics
calculations can be used to prove the experimental process.

Ultrathin single-crystal

1,2-dichloroethane containing chlorine
were used during the formation of PbS sheets. PbS ultrathin sheets probably resulted from the oriented attachment of the PbS nanoparticles in a two-dimensional fashion. The highly reactive facets were preferentially consumed in the growth process that led to the sheet-like PbS crystal growth.

Nanosheets can also be prepared at room temperature. For instance, hexagonal

gold nanoparticles as seeds under room temperature.[3] The size of the PbO nanosheet can be tuned by gold NPs and Pb2+
 concentration in the growth solution. No organic surfactants were employed in the synthesis process. Oriented attachment, in which the sheets form by aggregation of small nanoparticles that each has a net dipole moment,[12][13] and ostwald ripening[14] are the two main reasons for the formation of the PbO nanosheets. The same process was observed for iron sulfide nanoparticles.[15]

Carbon nanosheets have been produced using industrial hemp bast fibres with a technique that involves heating the fibres at over 350F (180C) for 24 hours. The result is then subjected to intense heat causing the fibers to exfoliate into a carbon nanosheet. This has been used to create an electrode for a supercapacitor with electrochemical qualities ‘on a par with’ devices made using graphene.[6]

Metal nanosheets have also been synthesized from solution-based method by reducing metal precursors, including palladium,[16] rhodium,[17] and gold.[18]

See also

References

  1. PMID 21292974
    .
  2. PMID 21283849
    .
  3. ^
    doi:10.1016/j.matlet.2011.09.048
    .
  4. PMID 19541989
    .
  5. ^ IBM Figures Out How to Make 5nm Chips. June 2017
  6. ^ a b "Could hemp nanosheets topple graphene for making the ideal supercapacitor?". acs.org. American Chemistry Society. Retrieved 14 August 2014.
  7. PMID 25369350
    .
  8. PMID 24347495
    .
  9. PMID 23071901
    .
  10. PMID 17038616
    .
  11. PMID 20671184
    .
  12. PMID 17397231
    .
  13. PMID 17038616
    .
  14. doi:10.1021/cg901148q
    .
  15. ISSN 1932-7447
    .
  16. PMID 25369350
    .
  17. PMID 24435210
    .
  18. PMID 16852818
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Nanosheet&oldid=1284111947"