Near Field Guided Chemical Nanopatterning

Abstract

This article demonstrates the possibility of creating well-defined and functional surface chemical nanopatterns using the optical near field of metal nanostructures and a photosensitive organic layer. The intensity distribution of the near field controlled the site and the extent of the photochemical reaction at the surface. The resulting pattern was used to guide the controlled assembly of colloids with a complementary surface functionality onto the substrate. Gold colloids of 20 nm diameter were covalently bound to the activated nanosites and proved the functionality of the suboptical wavelength structures and enabled direct visualization by means of electron microscopy. Our results prove, for the first time, the possibility of using optical near field to perform chemical reactions and assembly at the nanoscale.

Light‐Triggered Multifunctionality at Surfaces Mediated by Photolabile Protecting Groups

“…Strategy for near fi eld guided chemical nanopatterning followed by nanoparticle assembly (A). [ 72 ] The intensity distribution of the near fi eld controls the site and the extent of the two-photon cleavage of the nitroveratryl group at the surface. Upon cleavage, an amine functional group was released, which was used to site-selectively bind species with complementary chemical functionality on the surface.…”

“…Reproduced with permission. [ 72 ] and used in a similar manner for assembling target proteins (Figure 7 ). [ 83 ] It is important to note that proteins can interact with surfaces via multiple different interactions due to their complex structure.…”

Chirality and Chiroptical Effects in Plasmonic Nanostructures: Fundamentals, Recent Progress, and Outlook

“…These LSP can concentrate the electric field at the surface of nanostructures to very small spots ‐ the hotspots ‐ which can then serve as miniature molecular reactors. Within such hotspots, photochemical reactions,3 chemical transformations,4 and catalytic reactions can take place 5, 6. These processes are facilitated by the large amplitude of the local electric fields that can give rise to impressive signal enhancements, as in the case of Raman scattering,7 which can be increased up to fourteen orders of magnitude 8, 9.…”

Active molecular plasmonics: tuning surface plasmon resonances by exploiting molecular dimensions

“…Basically, active molecules should be confined within the plasmonic hot spots to maximize the plasmon-molecule coupling. It has been shown that selective functionalization with plasmon-activated photochemistry can be employed to achieve the site-selective control of molecules [123].…”