Hongyou Fan, University of New Mexico/Sandia National Laboratories
Mei Cai, General Motors Corporation
Yu Han, King Abdullah University of Science and Technology
Han Htoon, Los Alamos National Laboratory
Center for Integrated Nanotechnologies, Los Alamos National Laboratory
QN08.01: Nanoparticle Synthesis and Applications I
Monday AM, April 22, 2019
PCC North, 100 Level, Room 129 B
8:30 AM - *QN08.01.01
Growth and Transformation of Colloidal Nanostructures in Confined Spaces
University of California, Riverside1Show Abstract
Colloidal nanostructures have been studied quite extensively in the research area of heterogeneous catalysis long before the introduction of the concept of nanoscience and nanotechnology. The significant progress achieved in the past twenty years in chemical synthesis has enabled precise control over not only the size but also the shape of the metal nanostructures, and therefore attracted intense interest not only in catalysis but also optoelectronics due to the well-known effect of localized surface plasmon resonance. In this presentation, I will introduce our recent progress in the synthesis of colloidal metal nanostructures in confined spaces using various templating methods, their chemical transformation behavior, and further manipulation of their secondary structures. By combining the confinement of templates with the seed-mediated growth strategy, we demonstrate the significant advantages of this general method over the conventional ones in creating a large variety of nanomaterials with novel plasmonic properties.
9:00 AM - *QN08.01.02
On the Prenucleation Stage of Colloidal Semiconductor Quantum Dots
Sichuan University1Show Abstract
A worldwide interest during the past thirty years has been witnessed in the development of colloidal semiconductor nanocrystals (NCs). With significant efforts on the control of the size and size distribution, NC synthesis has been performed as an empirical art, lacking of fundamental understanding of the pre-nucleation stage also called the induction period. Colloidal semiconductor quantum dots (QDs) and magic sized clusters (MSCs) have been observed to evolve in a reaction together, sometimes. In this presentation, I will present our systematic study on their formation pathways. Based on our experimental data, we propose that there are two individual pathways in the prenucleation stage of the formation of QDs. The LaMer model of the classical nucleation theory (CNT) describes one pathway and the self-assembly of the cation and anion precursors is the other pathway which results in the formation of MSCs. We believe that our exploration of the prenucleation stage moves one step forward towards mechanism-enabled design and synthesis of NCs.
9:30 AM - *QN08.01.03
Ultrafast Photophysics Dynamics In Situ Quantum Dot Devices
Clemson University1Show Abstract
Quantum dot devices have wide applications in photovoltaics, optoelectronics, and sensors due to quantum dot unique quantum confinement effect, which can be tailed by size, shape, structure, and composition. Therefore, the ultrafast photophysics dynamics of charge carrier in situ devices (electrons, holes, or ions) including carrier transport, injection through optical or electrical, recombination, trapping, and transfer is one of the most fundamental questions.
We developed ultrafast photocurrent spectroscopy and ultrafast electroluminescence spectroscopy to address the ultrafast carrier dynamics in situ devices including solar cells, single-photon detectors, light emitting diodes, and photodetectors. In addition to that we understand ultrafast carrier transport and recombination dynamics, we discover novel photoconductivity phenomena, which cannot be addressed by other laser pump-probe spectroscopies.
10:30 AM - *QN08.01.04
Whole Cell Pathogen and Small Molecule Analytical Detection with Aptamer-Functionalized Particles
Lia Stanciu1,Susana Diaz-Amaya1,Li-Kai Lin1,Amanda Deering1
Purdue University1Show Abstract
Infectious outbreaks caused by foodborne pathogens such as E. coli O157:H7 are still occurring worldwide and cause acute illnesses and significant industrial impact. As a chemical component of organic materials, bisphenol A (BPA) is used in the food and consumer products industries. Despite its benefits, low-dose exposure to BPA adversely affects human health because it is an endocrine disrupting chemical (EDC).
We present on the feasibility of using aptameric DNA sequences, covalently conjugated to colloidal nanoparticles, for the sensitive and highly specific detection of whole cell pathogens and small molecule toxic molecules via surface enhanced Raman spectroscopy (SERS) analysis.
Low concentrations of E. coli O157:H7 were detected (~101 CFU/mL) and quantified (~102 CFU/mL) within 20 minutes in both pure culture and ground beef samples. We also report on a new range-extended bisphenol A (BPA) detection method that includes high-SERS-performance gold nanoparticles, i.e., 40 nm gold nanostars (GNSs) and 4-aminothiolphenol (4-ATP) as Raman reporters. The limit of detection for BPA was 0.073 ppb, which is 205 and 20 times more sensitive
than those of visual intensity and color intensity quantifications, respectively.
11:00 AM - QN08.01.05
Stoichiometric Preparations of Iron Oleate to Improve the Reproducibility of Iron Oxide Nanoparticle Syntheses
Dale Huber1,Sergei Ivanov2,Erika Vreeland3,John Watt1
Sandia National Laboratories1,Los Alamos National Laboratory2,IR Dynamics3Show Abstract
Iron Oleate has long been one of the most popular precursors for the synthesis of high-quality iron oxide nanoparticles. This is true despite the fact that it is not commercially available and must be custom synthesized. There are a handful of related syntheses that are in common use, but reproducibility of the synthesis is a significant concern. Iron oleate does not readily form a simple complex with one iron atom bonded to three oleate ligands as one might imagine. Instead, iron oleate often exists as a complex mixture of species that includes a series of oligomeric species with iron atoms bonded to each other through oxo bridges as well as other structure. This non-stoichiometric mixture is not easily purified as iron oleate resists the most common purification approaches. Iron oleate can not be recrystallized, as it does not crystallize and instead forms an oil or glass depending upon its temperature. Washing approaches are difficult to reproduce as the oleate ligands can be very labile, and repeated washes will continue to remove oleate ligands until it finally forms an insoluble solid. This lability of the oleates also make it difficult to purify the compound through chromatography as the compound can decompose on the column. Unfortunately, differences in the precursor synthesis can lead to difficulty in reproducing nanoparticles syntheses. We will discuss two approaches that have been demonstrated to yield highly reproducible iron oleate precursors. In the first approach, we produce iron oleate through the decomposition of another organometallic species in an excess of oleic acid yielding a solution of known stoichiometry that can be used without purification. In the second approach, judicious selection of reagents, solvents, and reaction conditions can yield an isolated compound of pure iron oleate with an iron:oleate ratio of exactly 1:3. These compounds can then be used to enhance the reproducibility of iron oxide nanoparticle syntheses. Sandia National Laboratories is a multimission laboratory managed and operated by National Technology and Engineering Solutions of Sandia LLC, a wholly owned subsidiary of Honeywell International Inc. for the DOE’s National Nuclear Security Administration under contract DE-NA0003525. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in the paper do not necessarily represent the views of the U.S. Department of Energy or the United States government.
11:15 AM - QN08.01.06
High ON-Current Vertical Field-Effect Transistors Based on Environmentally-Benign Quantum Dots
Jeongkyun Roh1,Hyeong Jin Yun1,Victor Klimov1
Los Alamos National Laboratory1Show Abstract
Colloidal quantum dots (QDs) have gained considerable attention as a new class of nanomaterials that can potentially enable the next-generation solution-processible electronic and optoelectronic devices (Science 353, aac5523, 2016). Owing to their superior optical properties, intense studies on QD-based color converters, light-emitting diodes (Nature 515, 96, 2014, Nat. Photon. 12, 159, 2018) and solar cells (Nat. Nanotechnol. 13, 456, 2018) have been underway leading to successful commercialization of the QD-display technology. The next frontier is exploration of electronically coupled QD solids in the context of prospective applications in solution-processible flexible electronics toward wearable electronic and sensing systems. One existing challenge in this area is low mobility of non-toxic QDs, which limits performance characteristics of non-toxic QD-based field-effect transistors (FETs) that represent basic building blocks of electronic circuits. Low mobilities lead to low ON-currents of typical QD-FETs. Increase in the current is possible by reducing the FET channel length, however, this would require the use of expensive and nonscalable patterning methods such as e-beam lithography.
Here, we demonstrate high ON-current QD FETs based on environmentally-benign QDs by employing a vertical architecture, which is a vertical stack of a gate electrode, a gate insulator, a source electrode, semiconducting transport layer, and a drain electrode. Using this approach, we reduce a channel length down to sub-micrometer scale, and as a result, achieve an unprecedented ON-current of ~0.1 A/cm2 in p-type QD FETs, which is three orders of magnitude higher than in standard lateral FETs. This notably high ON-current of vertical QD FETs is demonstrated using non-toxic Zn-doped CuInSe2 QDs (J. Am. Chem. Soc. 138, 4201, 2016) and achieved despite their low hole mobility of ~0.001 cm2/Vs. A switchable behavior of a vertical FET is enabled by the porous structure of a source electrode, which allows for the gate-controlled electric field to penetrate into a vertical channel and modulate a charge carrier density. The pattern of the source electrode is defined by optical interferometric lithography, which is a simple, fast, scalable and mask-less patterning method. To improve switching properties of the FET, a charge-blocking layer was applied to the top surface of the patterned source electrodes. This allows us to steer the charge flow in a lateral direction along the gate oxide interface, which is the channel region well-modulated by gate bias. Furthermore, we demonstrate polarity control of QD vertical FETs by employing indium diffusion to enable electron transport. The fabricated n-type vertical FETs exhibit even higher ON-currents approaching 1 A/cm2. Owing to high current density with a switchable behavior of the developed vertical QD-FETs, these devices can be used as a new platform to enable a variety of QD-based sensing, electronic and optoelectronic applications such as photodetector, light-emitting transistor, and infrared-to-visible up-converters.
11:30 AM - QN08.01.07
The Importance of ‘Beneficial Impurities’ in Surfactant Assisted Synthesis of Colloidal Nanoparticles
Ben Gurion University of the Negev1Show Abstract
While surfactant assisted synthesis is probably the most common technique for the preparation of colloidal nanoparticles, workers in the field often encounter severe irreproducibility issues. In this talk, we will present several examples, from our work [1,2], as well as by others [3-5], for the role of ‘beneficial impurities’ in nanoparticle synthesis. Furthermore, a new binary phase of cubic nanocrystalline semiconductors has been discovered in recent years in the form of colloidal nanoparticles. The first materials to be discovered were π tin mono-sulfide [6,7] and π tin mono-selenide , yet density functional theory calculations predict the existence of additional potentially useful compound semiconductors in the π structure. There is growing experimental evidence that phase control in the tin mono-chalcogenide system is likely to be governed by ‘beneficial impurities’ as well.
1. N. Belman, J.N. Israelachvili, Y. Li, C.R. Safinya, J. Bernstein and Y. Golan, Nano Lett. 9 (2009) 2088.
2. N. Belman, J.N. Israelachvili, Y. Li, C.R. Safinya, J. Bernstein and Y. Golan, J. Am. Chem. Soc. 131 (2009) 9107.
3. F. Wang, R. Tang, W.E. Buhro, Nano Lett. 8 (2008) 3521.
4. J.E. Millstone, W. Wei, M.R. Jones, H. Yoo, C.A. Mirkin, Nano Lett. 8 (2008) 2526.
5. D.K. Smith, N.R. Miller, B.A. Korgel, Langmuir 25 (2009) 9518.
6. A. Rabkin, S. Samuha, R.E. Abutbul, V. Ezersky, L. Meshi, Y. Golan, Nano Lett. 15 (2015) 2174-2179.
7. R.E. Abutbul, E. Segev, L. Zeiri, V. Ezersky, G. Makov, Y. Golan, RSC Adv. 6 (2016) 5848-5855.
8. R.E. Abutbul, E. Segev, S. Samucha, L. Zeiri, V. Ezersky, G. Makov, Y. Golan, CrystEngComm 18 (2016) 1918-1923.
9. R. E. Abutbul, E. Segev, U. Argaman, G. Makov, and Y. Golan, Adv. Mater. 30 (2018) 1706285.
QN08.02: Nanoparticle, Synthesis, Assembly and Applications I
Monday PM, April 22, 2019
PCC North, 100 Level, Room 129 B
1:30 PM - *QN08.02.01
Fabrication of Arrays of Highly Complex Noble Metal Nanostructures Using Nanoimprint Lithography in Combination with Liquid-Phase Epitaxy
Svetlana Neretina1,Robert Hughes1,Spencer Golze1,Arin Preston1,Trevor Demille1
University of Notre Dame1Show Abstract
Current best-practice lithographic techniques are unable to meet the functional requirements needed to enable on-chip plasmonic devices capable of fully exploiting nanostructure properties reliant on a tailored nanostructure size, composition, architecture, crystallinity, and placement. As a consequence, numerous nanofabrication methods have emerged that address various weaknesses, but none have, as of yet, demonstrated a large-area processing route capable of defining organized surfaces of nanostructures with the architectural diversity and complexity that is routinely displayed in colloidal syntheses. Here, a hybrid fabrication strategy is demonstrated in which nanoimprint lithography is combined with templated dewetting and liquid-phase syntheses that is able to realize periodic arrays of complex noble metal nanostructures over square centimeter areas. The process is inexpensive, can be carried out on a benchtop, and requires modest levels of instrumentation. Demonstrated are three fabrication schemes yielding arrays of core–shell, core–void–shell, and core–void–nanoframe structures using liquid-phase syntheses involving heteroepitaxial deposition, galvanic replacement, and dealloying. With the field of nanotechnology being increasingly reliant on the engineering of desirable physicochemical responses through architectural control, the fabrication strategy provides a platform for advancing devices reliant on addressable arrays or the collective response from an ensemble of identical nanostructures.
2:00 PM - *QN08.02.02
Si Microparticle Based Electrode for Effective Stress Relaxation and Stable Electrochemical Cycling
Seung Min Han1,Donghyuk Kim1,Minkyu Park1,Hyungcheoul Shim2,Seungmin Hyun2
Korea Advanced Institute of Science and Technology1,Korea Institute of Machinary and Materials2Show Abstract
Si anode of a lithium ion battery undergoes extreme volume expansions during lithiation and delithiation cycles. Finite element analysis indicates that significant build-up of lithiation-induced stresses can develop that results in fracture of the Si anode material. In this study, we report two different designs for Si microparticle based composite anode that allows for relaxation of the diffusion induced stresses in the Si microparticles. Self-healing polymer and Si microparticle freestanding composite was proposed and analyzed for its cyclic stability that confirmed enhanced retention, with the freestanding composite demonstrating 91.8% capacity retention after 100 cycles at C/10 rate. Second design for the composite anode uses Si microparticles that are embedded in combustion reacted, nanoporous ZnO. The nanoporous ZnO was shown to in itself undergo conversion reaction that hence increased the capacity and also was shown to help in maintaining the coalescence of SiMPs for enhanced electrochemical cycling, which yielded a binder-less design with an initial capacity of ~3,900 mAh/g at C/20 rate and a reversible capacity of ~1,500 mAh/g beyond 200 cycles at C/5 rate. In addition, the Li2O/Zn matrix derived from conversion-reacted nanoporous ZnO acted as an effective buffer to lithiation-induced stresses from volume expansion and served as a binder-like matrix that contributed to the overall electrode capacity and stability.
2:30 PM - *QN08.02.03
Hybrid Metal- Inorganic Nanoparticle—Core-Shell Dendrimers and Star Copolymers
Case Western Reserve University1Show Abstract
The preparation of new nanomaterials requires hierarchical levels of ordering and structuring: from molecular to macroscopic. Much has been demonstrated in metal, metal oxide, inorganic nanoparticles by way of size, shape, and polydispersity control. The Plasmonic and emissive properties dependent on size, shape, and hot spots are well known. Dendrimers and other hyperbranched polymer systems are of interest for their functionality in catalysis, drug delivery, reactivity, etc. Of high interest are dendrimer functionality in electro-optical applications and nanopatterning. This includes dendrimers capable of hierarchical ordering and self-assembly. We highlight the convergent synthesis of a variety of hybrid nanoparticle dendrimers and their electropolymerizability. The synthesis of precise dendrons as modular building blocks for functional dendrimers and the use of star copolymers for various core-shell architectures are demonstrated. Our group has reported a number of these hybrid systems and have reported the step-by-step routes towards structure-property relationships. These has resulted in controlled charge -transfer and energy transfer properties not to mention the ability to provide greater stability for these nanoparticles. What is also important is the use of surface sensitive spectroscopic and microscopic analytical tools applied rationally to highlight evidence of order and function.
3:30 PM - *QN08.02.04
Design Nanostructured Si materials for Practical Anodes of Next Generation Li-Ion Batteries
Xiaolin Li1,Haiping Jia1,Ji-Guang Zhang1
Pacific Northwest National Laboratory1Show Abstract
Nanostructured materials have been found to be critical in promoting the performance of energy storage and conversion devices, such as batteries. Here, several nanostructured Si materials have been designed for practical anodes of high energy Li-ion batteries (LIBs). In one effort, the large (>20 μm) mesoporous Si sponge prepared have controlled porosity and pore size, which can limit the particle volume expansion at full lithiation to ~30% and prevent pulverization of bulk particles. The porous Si anodes deliver a specific capacity of up to ~750 mAh/g based on the total electrode weight and >80% capacity retention over 1,000 cycles. The electrodes with the loading of ~1.5 mAh/cm2 demonstrated ~92% capacity retention over 300 cycles. The composite electrodes of porous Si and graphite (~3 mAh/cm2 loading) with a specific capacity of ~650 mAh/g demonstrate ~82% capacity retention over 450 cycles. In another effort, hierarchical structured Si/CNT microspheres developed not only have good porous structure to accommodate the volume expansion and achieve ~30% apparent particle swell at full lithiation, but also demonstrate good mechanical integrity with the structure sustained up to ~200 MPa pressure. The anodes deliver a high specific capacity of ~1500 mAh/g and 85% capacity retention over 200 cycles at the areal loading of ~3 mAh/cm2.
4:00 PM - QN08.02.05
Light Activated Synthesis of Periodic Arrays of Metallic Nanoplates
Robert Hughes1,Svetlana Neretina1,Spencer Golze1,Sergei Rouvimov1
University of Notre Dame1Show Abstract
Our laboratory has developed a new synthetic procedure for generating periodic arrays of metallic nanostructures shaped as hexagonal or triangular nanoplates using a room temperature light-activated growth mode. Such structures have the potential to act as the active components for the detection of biological and chemical analytes using various sensing modalities (e.