Subscriber access provided by NEW YORK MED COLL
Article
Gold nanooctahedra with tunable size and Microfluidic-Induced 3D assembly for Highly Uniform SERS-active Supercrystals Sergio Gómez-Graña, Cristina Fernández-López, Lakshminarayana Polavarapu, Jean Baptiste Salmon, Jacques Leng, Isabel Pastoriza-Santos, and Jorge Perez-Juste Chem. Mater., Just Accepted Manuscript • DOI: 10.1021/acs.chemmater.5b03620 • Publication Date (Web): 16 Oct 2015 Downloaded from http://pubs.acs.org on October 17, 2015
Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.
Chemistry of Materials is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.
Page 1 of 26
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Chemistry of Materials
Gold nanooctahedra with tunable size and Microfluidic-Induced 3D assembly for Highly Uniform SERS-active Supercrystals Sergio Gómez-Graña,a,† Cristina Fernández-López,b,† Lakshminarayana Polavarapu,b JeanBaptiste Salmon,a Jacques Leng,a Isabel Pastoriza-Santos,b,* Jorge Pérez-Justeb,*
a
Université Bordeaux, Laboratoire du Futur, SOLVAY, CNRS, 178 avenue Schweitzer, F-33600 Pessac, France
b
Departamento de Quıímica Física, Universidade de Vigo, 36310, Spain
Corresponding Authors
[email protected] (I. Pastoriza-Santos)
[email protected] (J. Pérez-Juste) †
These authors have contributed equally to the work
1 ACS Paragon Plus Environment
Chemistry of Materials
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Abstract Shape-controlled synthesis of uniform noble metal nanoparticles (NPs) is crucial for the development of future plasmonic devices. The use of nanocrystals with well-defined morphologies and crystallinity as seed particles is expected to provide excellent shape control and monodispersity. We report the aqueous-based seed-mediated growth of monodisperse gold octahedra with wide range of sizes (50-150 nm in side length) by reducing different amounts of HAuCl4 on preformed single crystalline gold nanorods using butenoic acid as reducing agent. Butenoic acid plays a key role as a mild reducing agent as well as favoring the thermodynamic control of the reaction. The uniformity of the as-prepared Au octahedra combined with the use of a microfluidic technique based on microevaporation will allow the self-assembly of octahedra into uniform 3D supercrystals. Additionally, these plasmonic substrates exhibit high and uniform SERS signals over extended areas with intensities increasing with the Au nanoparticle size.
2 ACS Paragon Plus Environment
Page 2 of 26
Page 3 of 26
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60
Chemistry of Materials
INTRODUCTION Over the years, colloidal plasmonic nanocrystals have emerged as important building blocks of modern nanoscience and nanotechnology to deal with a wide range of applications including electronics, energy, medicine, catalysis, biosensing, imaging and therapy.1-7 Most of these applications have been developed through the use of rich optical properties of plasmonic nanostructures that arise from the strong localized surface plasmon resonances (LSPRs).1-6,8 The LSPR is strongly dependent on the shape of nanoparticles (NPs), among other parameters. Therefore, shape-controlled synthesis of noble metal nanocrystals has attracted great attention during the last two decades.9,10 As a result numerous synthetic methods have been developed to prepare nanocrystals with different morphologies.9,11,12 Among all, the seed-mediated growth approach has emerged as a reliable and versatile method for the preparation of a wide variety of morphologies such as spheres, rods, cubes, octahedral, decahedra and triangles.9,13,14 This technique is based on the overgrowth of preformed small nanoparticles (seed) via reduction a metal salt precursor with a mild reducing agent.5,9,13 It has demonstrated that seed crystallinity is one of the main parameters determining the final NPs morphology.9 Often small particles (
