TY - JOUR

T1 - Macroscopic Aerogels with Retained Nanoscopic Plasmonic Properties

AU - Kodanek, Torben

AU - Freytag, Axel

AU - Schlosser, Anja

AU - Naskar, Suraj

AU - Härtling, Thomas

AU - Dorfs, Dirk

AU - Bigall, Nadja Carola

N1 - Funding information:: T. K. and D. D. want to thank the German research foundation (DFG, research grants DO1580/2-1 and DO1580/3-1) for funding. A. F., S. N. and N. C. B. are thankful for the financial support to German Ministry of Education and research (BMBF, NanoMatFutur, support code 03X5525). For the funding from the European Research Council (Horizon 2020, grant agreement No 714429/ERC Starting Grant MAEROSTRUC) the N. C. B. is also grateful. Moreover, T. K. and A. S. are grateful to the Hannover School for Nanotechnology (hsn) for the financial support.

PY - 2018/8/28

Y1 - 2018/8/28

N2 - Aerogels can bridge the nanoscopic to the macroscopic world. One physical phenomenon typically limited to the nanoscopic world is the occurrence of localized surface plasmon resonances (LSPRs), which are observed in conductive nanoparticles. Once brought into close contact, assemblies or superstructures of these nanoparticles often lose their plasmonic properties in the transition stage towards the bulk material. Therefore, LSPRs are typically not observed in macroscopic objects. The present work aims at voluminous nanoparticle-based aerogels with optical properties close to that of the initial colloidal solution and the possibility to manipulate the final plasmonic properties by bringing the particles into defined distances. In detail, Ag nanocrystals with silica shells ranging from 0 to 12 nm are employed as building blocks, which are assembled from their solution into macroscopic three-dimensional superstructures by freezing and subsequent lyophilization. These cryogelated aerogels are synthesized as monoliths and thin films in which the Ag nanocrystals are arranged in defined distances according to their silica shell. The resulting aerogels exhibit plasmonic properties ranging from a behavior similar to that of the building blocks for the thickest shell to a heavily distorted behavior for bare Ag nanocrystals.

AB - Aerogels can bridge the nanoscopic to the macroscopic world. One physical phenomenon typically limited to the nanoscopic world is the occurrence of localized surface plasmon resonances (LSPRs), which are observed in conductive nanoparticles. Once brought into close contact, assemblies or superstructures of these nanoparticles often lose their plasmonic properties in the transition stage towards the bulk material. Therefore, LSPRs are typically not observed in macroscopic objects. The present work aims at voluminous nanoparticle-based aerogels with optical properties close to that of the initial colloidal solution and the possibility to manipulate the final plasmonic properties by bringing the particles into defined distances. In detail, Ag nanocrystals with silica shells ranging from 0 to 12 nm are employed as building blocks, which are assembled from their solution into macroscopic three-dimensional superstructures by freezing and subsequent lyophilization. These cryogelated aerogels are synthesized as monoliths and thin films in which the Ag nanocrystals are arranged in defined distances according to their silica shell. The resulting aerogels exhibit plasmonic properties ranging from a behavior similar to that of the building blocks for the thickest shell to a heavily distorted behavior for bare Ag nanocrystals.

KW - aerogels

KW - core-shell heterostructures

KW - plasmon coupling

KW - silver nanoparticles

UR - http://www.scopus.com/inward/record.url?scp=85042157016&partnerID=8YFLogxK

U2 - 10.1515/zpch-2017-1045

DO - 10.1515/zpch-2017-1045

M3 - Article

AN - SCOPUS:85042157016

VL - 232

SP - 1675

EP - 1689

JO - Zeitschrift fur Physikalische Chemie

JF - Zeitschrift fur Physikalische Chemie

SN - 0942-9352

IS - 9-11

ER -