Mesoflowers: A new class of highly efficient surface-enhanced Raman active and infrared-absorbing materials
Mesoflowers, gold nanoparticles, seed-mediated growth, IR absorption, surface-enhanced Raman scattering (SERS)
A method for the synthesis of a new class of anisotropic mesostructured gold material, which we call “mesoflowers”, is demonstrated. The mesoflowers, unsymmetrical at the single particle level, resemble several natural objects and are made up of a large number of stems with unusual pentagonal symmetry. The mesostructured material has a high degree of structural purity with star-shaped, nano-structured stems. The mesoﬂ owers were obtained in high yield, without any contaminating structures and their size could be tuned from nano- to meso-dimensions. The dependence of various properties of the mesoﬂ owers on their conditions of formation was studied. The near-infrared infrared (NIR IR) absorption exhibited by the mesoﬂ owers has been used for the development of infrared ﬁ lters. Using a prototypical device, we demonstrated the utility of the gold mesoﬂ owers in reducing the temperature rise in an enclosure exposed to daylight in peak summer. These structures showed a high degree of surface-enhanced Raman scattering (SERS) activity compared to spherical analogues. SERS-based imaging of a single mesoﬂ ower is demonstrated. The high SERS activity and NIR IR absorption property open up a number of exciting applications in diverse areas.
Tsinghua University Press
Panikkanvalappil Ravindranathan Sajanlal,Thalappil Pradeep, Mesoflowers: A new class of highly efficient surface-enhanced Raman active and infrared-absorbing materials. NanoRes.2009, 2: 306-320