1
|
Sánchez-Iglesias A, Grzelczak M. Expanding Chemical Space in the Synthesis of Gold Bipyramids. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2407735. [PMID: 39520337 DOI: 10.1002/smll.202407735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2024] [Revised: 10/24/2024] [Indexed: 11/16/2024]
Abstract
Gold bipyramids (AuBPs), despite having superior properties compared to their spectroscopically similar counterparts, gold nanorods, have found comparatively limited applications. This discrepancy is primarily due to the lack of protocols to tailor their dimensions. Typically, the concentration of Au seeds is virtually the sole factor that determines the aspect ratio and thus, the optical properties of AuBPs. As a result, varying the volumes of AuBPs while incurring minimal changes to their optical spectra remains a synthetically non-trivial task. Here, the chemical space in the seeded growth of AuBPs, is expanded by exploiting the interplay between bromide, silver ions, and seed concentration for tuning the final dimensions and optical properties of AuBPs. Specifically, a 6 fold change in volumes of AuBPs is achieved while maintaining the fixed plasmon band position. Further overgrowth of as-prepared bipyramids broadens the realizable dimensions without compromising quality and initial morphology. Overall, the results expand the chemical toolbox in the wet-chemistry synthesis of anisotropic gold nanoparticles, which is relevant for health, colorimetric sensors, and energy applications.
Collapse
|
2
|
Kemper U, Weizenmann N, Kielar C, Erbe A, Seidel R. Heavy Metal Stabilization of DNA Origami Nanostructures. NANO LETTERS 2024; 24:2429-2436. [PMID: 38363878 PMCID: PMC10905993 DOI: 10.1021/acs.nanolett.3c03751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 02/09/2024] [Accepted: 02/12/2024] [Indexed: 02/18/2024]
Abstract
DNA origami is a powerful tool to fold 3-dimensional DNA structures with nanometer precision. Its usage, however, is limited as high ionic strength, temperatures below ∼60 °C, and pH values between 5 and 10 are required to ensure the structural integrity of DNA origami nanostructures. Here, we demonstrate a simple and effective method to stabilize DNA origami nanostructures against harsh buffer conditions using [PdCl4]2-. It provided the stabilization of different DNA origami nanostructures against mechanical compression, temperatures up to 100 °C, double-distilled water, and pH values between 4 and 12. Additionally, DNA origami superstructures and bound cargos are stabilized with yields of up to 98%. To demonstrate the general applicability of our approach, we employed our protocol with a Pd metallization procedure at elevated temperatures. In the future, we think that our method opens up new possibilities for applications of DNA origami nanostructures beyond their usual reaction conditions.
Collapse
|
3
|
Yang Y, Lu X, Zhang H, Yu X, Zheng Q, Wang Z. Fabrication of b-oriented MFI zeolite membranes by a novel printing-transfer seed layer procedure. Chem Asian J 2023:e202300218. [PMID: 37062962 DOI: 10.1002/asia.202300218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 04/18/2023]
Abstract
Highly b-oriented MFI zeolite (abbreviated as BOMZ) membranes are attractive due to less grain boundary defects and straight channels normal to the substrate, enhancing selectivity and flux in membrane separation. Herein, we demonstrate a novel, effective and easily-amplified printing-transfer oriented-seed-layer technique to manufacture uniform BOMZ seed monolayer on porous supports. Furthermore, a facile and effective approach for the synthesis of highly BOMZ membranes by introducing poly(hexamethylene biguanide) hydrochloride as a twin crystal inhibitor during seeded growth is demonstrated. Well-intergrown BOMZ membranes (~650 nm thick) obtained on porous Al2O3 supports show a flux of 2.8 kg m-2 h-1 with a separation factor as high as 71 for pervaporation in the 60 oC feed of EtOH/H2O (5 wt%), which is much higher than those of random membranes. The developed seed assembly technique on porous supports underlines great potential for facile preparation of oriented seed layers on porous supports.
Collapse
|
4
|
Kemper U, Ye J, Poppitz D, Gläser R, Seidel R. DNA Mold-Based Fabrication of Palladium Nanostructures. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023:e2206438. [PMID: 36960479 DOI: 10.1002/smll.202206438] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Revised: 02/03/2023] [Indexed: 06/18/2023]
Abstract
DNA origami molds allow a shape-controlled growth of metallic nanoparticles. So far, this approach is limited to gold and silver. Here, the fabrication of linear palladium nanostructures with controlled lengths and patterns is demonstrated. To obtain nucleation centers for a seeded growth, a synthesis procedure of palladium nanoparticles (PdNPs) using Bis(p-sulfonatophenyl)phenylphosphine (BSPP) both as reductant and stabilizer is developed to establish an efficient functionalization protocol of the particles with single-stranded DNA. Attaching the functionalized particles to complementary DNA strands inside DNA mold cavities supports subsequently a highly specific seeded palladium deposition. This provides rod-like PdNPs with diameters of 20-35 nm of grainy morphology. Using an annealing procedure and a post-reduction step with hydrogen, homogeneous palladium nanostructures can be obtained. With the adaptation of the procedure to palladium the capabilities of the mold-based tool-box are expanded. In the future, this may allow a facile adaptation of the mold approach to less noble metals including magnetic materials such as Ni and Co.
Collapse
|
5
|
Zhuo X, Mychinko M, Heyvaert W, Larios D, Obelleiro-Liz M, Taboada JM, Bals S, Liz-Marzán LM. Morphological and Optical Transitions during Micelle-Seeded Chiral Growth on Gold Nanorods. ACS NANO 2022; 16:19281-19292. [PMID: 36288463 DOI: 10.1021/acsnano.2c08668] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Chiral plasmonics is a rapidly developing field where breakthroughs and unsolved problems coexist. We have recently reported binary surfactant-assisted seeded growth of chiral gold nanorods (Au NRs) with high chiroptical activity. Such a seeded-growth process involves the use of a chiral cosurfactant that induces micellar helicity, in turn driving the transition from achiral to chiral Au NRs, from both the morphological and the optical points of view. We report herein a detailed study on both transitions, which reveals intermediate states that were hidden so far. The correlation between structure and optical response is carefully analyzed, including the (linear and CD) spectral evolution over time, electron tomography, the impact of NR dimensions on their optical response, the variation of the absorption-to-scattering ratio during the evolution from achiral to chiral Au NRs, and the near-field enhancement related to chiral plasmon modes. Our findings provide further understanding of the growth process of chiral Au NRs and the associated optical changes, which will facilitate further study and applications of chiral nanomaterials.
Collapse
|
6
|
Nobile C, Cozzoli PD. Synthetic Approaches to Colloidal Nanocrystal Heterostructures Based on Metal and Metal-Oxide Materials. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:1729. [PMID: 35630951 PMCID: PMC9147683 DOI: 10.3390/nano12101729] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Revised: 04/30/2022] [Accepted: 05/09/2022] [Indexed: 12/04/2022]
Abstract
Composite inorganic nanoarchitectures, based on combinations of distinct materials, represent advanced solid-state constructs, where coexistence and synergistic interactions among nonhomologous optical, magnetic, chemical, and catalytic properties lay a basis for the engineering of enhanced or even unconventional functionalities. Such systems thus hold relevance for both theoretical and applied nanotechnology-based research in diverse areas, spanning optics, electronics, energy management, (photo)catalysis, biomedicine, and environmental remediation. Wet-chemical colloidal synthetic techniques have now been refined to the point of allowing the fabrication of solution free-standing and easily processable multicomponent nanocrystals with sophisticated modular heterostructure, built upon a programmed spatial distribution of the crystal phase, composition, and anchored surface moieties. Such last-generation breeds of nanocrystals are thus composed of nanoscale domains of different materials, assembled controllably into core/shell or heteromer-type configurations through bonding epitaxial heterojunctions. This review offers a critical overview of achievements made in the design and synthetic elaboration of colloidal nanocrystal heterostructures based on diverse associations of transition metals (with emphasis on plasmonic metals) and transition-metal oxides. Synthetic strategies, all leveraging on the basic seed-mediated approach, are described and discussed with reference to the most credited mechanisms underpinning regioselective heteroepitaxial deposition. The unique properties and advanced applications allowed by such brand-new nanomaterials are also mentioned.
Collapse
|
7
|
Storozhuk L, Besenhard MO, Mourdikoudis S, LaGrow AP, Lees MR, Tung LD, Gavriilidis A, Thanh NTK. Stable Iron Oxide Nanoflowers with Exceptional Magnetic Heating Efficiency: Simple and Fast Polyol Synthesis. ACS APPLIED MATERIALS & INTERFACES 2021; 13:45870-45880. [PMID: 34541850 DOI: 10.1021/acsami.1c12323] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Magnetically induced hyperthermia has reached a milestone in medical nanoscience and in phase III clinical trials for cancer treatment. As it relies on the heat generated by magnetic nanoparticles (NPs) when exposed to an external alternating magnetic field, the heating ability of these NPs is of paramount importance, so is their synthesis. We present a simple and fast method to produce iron oxide nanostructures with excellent heating ability that are colloidally stable in water. A polyol process yielded biocompatible single core nanoparticles and nanoflowers. The effect of parameters such as the precursor concentration, polyol molecular weight as well as reaction time was studied, aiming to produce NPs with the highest possible heating rates. Polyacrylic acid facilitated the formation of excellent nanoheating agents iron oxide nanoflowers (IONFs) within 30 min. The progressive increase of the size of the NFs through applying a seeded growth approach resulted in outstanding enhancement of their heating efficiency with intrinsic loss parameter up to 8.49 nH m2 kgFe-1. The colloidal stability of the NFs was maintained when transferring to an aqueous solution via a simple ligand exchange protocol, replacing polyol ligands with biocompatible sodium tripolyphosphate to secure the IONPs long-term colloidal stabilization.
Collapse
|
8
|
Sarkar A, Sasmal R, Das A, Venugopal A, Agasti SS, George SJ. Tricomponent Supramolecular Multiblock Copolymers with Tunable Composition via Sequential Seeded Growth. Angew Chem Int Ed Engl 2021; 60:18209-18216. [PMID: 34111324 DOI: 10.1002/anie.202105342] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/25/2021] [Indexed: 01/28/2023]
Abstract
Synthesis of supramolecular block co-polymers (BCP) with small monomers and predictive sequence requires elegant molecular design and synthetic strategies. Herein we report the unparalleled synthesis of tri-component supramolecular BCPs with tunable microstructure by a kinetically controlled sequential seeded supramolecular polymerization of fluorescent π-conjugated monomers. Core-substituted naphthalene diimide (cNDI) derivatives with different core substitutions and appended with β-sheet forming peptide side chains provide perfect monomer design with spectral complementarity, pathway complexity and minimal structural mismatch to synthesize and characterize the multi-component BCPs. The distinct fluorescent nature of various cNDI monomers aids the spectroscopic probing of the seeded growth process and the microscopic visualization of resultant supramolecular BCPs using Structured Illumination Microscopy (SIM). Kinetically controlled sequential seeded supramolecular polymerization presented here is reminiscent of the multi-step synthesis of covalent BCPs via living chain polymerization. These findings provide a promising platform for constructing unique functional organic heterostructures for various optoelectronic and catalytic applications.
Collapse
|
9
|
Ye J, Aftenieva O, Bayrak T, Jain A, König TAF, Erbe A, Seidel R. Complex Metal Nanostructures with Programmable Shapes from Simple DNA Building Blocks. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2021; 33:e2100381. [PMID: 34085729 PMCID: PMC11469289 DOI: 10.1002/adma.202100381] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 03/01/2021] [Indexed: 06/12/2023]
Abstract
Advances in DNA nanotechnology allow the design and fabrication of highly complex DNA structures, uisng specific programmable interactions between smaller nucleic acid building blocks. To convey this concept to the fabrication of metallic nanoparticles, an assembly platform is developed based on a few basic DNA structures that can serve as molds. Programming specific interactions between these elements allows the assembly of mold superstructures with a range of different geometries. Subsequent seeded growth of gold within the mold cavities enables the synthesis of complex metal structures including tightly DNA-caged particles, rolling-pin- and dumbbell-shaped particles, as well as T-shaped and loop particles with high continuity. The method further supports the formation of higher-order assemblies of the obtained metal geometries. Based on electrical and optical characterizations, it is expected that the developed platform is a valuable tool for a self-assembly-based fabrication of nanoelectronic and nanooptic devices.
Collapse
|
10
|
Xia C, van Oversteeg CHM, Bogaards VCL, Spanjersberg THM, Visser NL, Berends AC, Meeldijk JD, de Jongh PE, de Mello Donega C. Synthesis and Formation Mechanism of Colloidal Janus-Type Cu 2-xS/CuInS 2 Heteronanorods via Seeded Injection. ACS NANO 2021; 15:9987-9999. [PMID: 34110780 PMCID: PMC8291760 DOI: 10.1021/acsnano.1c01488] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Accepted: 06/08/2021] [Indexed: 06/12/2023]
Abstract
Colloidal heteronanocrystals allow for the synergistic combination of properties of different materials. For example, spatial separation of the photogenerated electron and hole can be achieved by coupling different semiconductors with suitable band offsets in one single nanocrystal, which is beneficial for improving the efficiency of photocatalysts and photovoltaic devices. From this perspective, axially segmented semiconductor heteronanorods with a type-II band alignment are particularly attractive since they ensure the accessibility of both photogenerated charge carriers. Here, a two-step synthesis route to Cu2-xS/CuInS2 Janus-type heteronanorods is presented. The heteronanorods are formed by injection of a solution of preformed Cu2-xS seed nanocrystals in 1-dodecanethiol into a solution of indium oleate in oleic acid at 240 °C. By varying the reaction time, Janus-type heteronanocrystals with different sizes, shapes, and compositions are obtained. A mechanism for the formation of the heteronanocrystals is proposed. The first step of this mechanism consists of a thiolate-mediated topotactic, partial Cu+ for In3+ cation exchange that converts one of the facets of the seed nanocrystals into CuInS2. This is followed by homoepitaxial anisotropic growth of wurtzite CuInS2. The Cu2-xS seed nanocrystals also act as sacrificial Cu+ sources, and therefore, single composition CuInS2 nanorods are eventually obtained if the reaction is allowed to proceed to completion. The two-stage seeded growth method developed in this work contributes to the rational synthesis of Cu2-xS/CuInS2 heteronanocrystals with targeted architectures by allowing one to exploit the size and faceting of premade Cu2-xS seed nanocrystals to direct the growth of the CuInS2 segment.
Collapse
|
11
|
Zhang G, Ma Y, Liu F, Tong Z, Sha J, Zhao W, Liu M, Zheng Y. Seeded Growth of Au@Cu xO Core-Shell Mesoporous Nanospheres and Their Photocatalytic Properties. Front Chem 2021; 9:671220. [PMID: 33968907 PMCID: PMC8103172 DOI: 10.3389/fchem.2021.671220] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 04/01/2021] [Indexed: 11/16/2022] Open
Abstract
We report a facile synthesis of Au@CuxO core-shell mesoporous nanospheres with tunable size in the aqueous phase via seeded growth. The success of the current work relies on the use of a halide-free copper (Cu) precursor and n-oleyl-1,3-propanediamine as a capping agent to facilitate the formation of a copperish oxide shell with a mesoporous structure and the presence of mixed oxidation states of Cu. By varying the amount of spherical Au seeds while keeping other parameters unchanged, their diameters could be readily tuned without noticeable change in morphology. As compared with commercial Cu2O, the as-prepared Au@CuxO core-shell mesoporous nanospheres exhibit the higher adsorption ability, enhanced activity, and excellent stability toward photocatalytic degradation of methyl orange (MO) under visible light irradiation, indicating their potential applications in water treatment.
Collapse
|
12
|
The Influence of Different Classes of Amino Acids on Calcium Phosphates Seeded Growth. MATERIALS 2020; 13:ma13214798. [PMID: 33121165 PMCID: PMC7662258 DOI: 10.3390/ma13214798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 10/22/2020] [Accepted: 10/22/2020] [Indexed: 11/23/2022]
Abstract
Amino acids (AAs) attract attention for elucidating the role of proteins in biomineralization and the preparation of functionalized biomaterials. The influence that AAs exert on calcium phosphate (CaP) mineralization is still not completely understood, as contradictory results have been reported. In this paper, the influence of the addition of different classes of AAs, charged (L-aspartic acid, Asp; L-lysine, Lys), polar (L-asparagine, Asn; L-serine, Ser; L-tyrosine, Tyr), and non-polar (L-phenylalanine, Phe), on CaP growth in the presence of octacalcium phosphate (OCP) and calcium hydrogenphosphate dihydrate (DCPD) seeds was investigated. In control systems (without AAs), a calcium-deficient apatite (CaDHA) layer was formed on the surface of OCP, while a mixture of CaDHA and OCP in the form of spherical aggregates was formed on the surface of DCPD crystals. Charged and non-polar promoted, while polar AAs inhibited CaDHA formation on the OCP seeds. In the case of DCPD, Lys, Asp, and Phe promoted CaP formation, while the influence of other AAs was negligible. The most efficient promotor of precipitation in both cases was non-polar Phe. No significant influence of AAs on the composition and morphology of precipitates was observed. The obtained results are of interest for understanding biomineralization processes and additive controlled material synthesis.
Collapse
|
13
|
Cao K, Cheng Y, Chen J, Huang Y, Ge M, Qian J, Liu L, Feng J, Chen S, Huang W. Regulated Crystallization of FASnI 3 Films through Seeded Growth Process for Efficient Tin Perovskite Solar Cells. ACS APPLIED MATERIALS & INTERFACES 2020; 12:41454-41463. [PMID: 32829633 DOI: 10.1021/acsami.0c11253] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Although rapid progress has been made in tin-based perovskite solar cells (PSCs), the inferior film qualities of the solution-processed perovskites always lead to poor reproducibility and instability. Herein, we present a simple seeded growth (SG) approach to obtain high-quality tin-based perovskite films with preferred crystal orientation, large grain sizes, and fewer apparent grain boundaries. High-quality tin-based perovskite films fabricated through this SG process could greatly reduce the nonradiative recombination centers and inhibit the oxidation of Sn2+. Using formamidinium tin tri-iodide (FASnI3) perovskites, the SG-PSCs exhibit a much improved efficiency from 5.37% (control) to 7.32% with all improved photovoltaic parameters. Moreover, this SG strategy is easily applicable to other tin-based perovskite compositions. The PSC based on methylammonium (MA) doped mixed-cation perovskite (FA0.75MA0.25SnI3) exhibited a power conversion efficiency (PCE) of 8.54% with an improvement of 19.3% in the photovoltaic performance, making it a general approach for achieving efficient tin-based PSCs.
Collapse
|
14
|
Seeded Growth Synthesis of Zirconia@Gold Particles in Aqueous Solution. NANOMATERIALS 2020; 10:nano10061197. [PMID: 32575397 PMCID: PMC7353092 DOI: 10.3390/nano10061197] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 06/12/2020] [Accepted: 06/16/2020] [Indexed: 11/16/2022]
Abstract
Metal-ceramic composite particles are of increasing interest due to their potential applications in photonic metamaterials as well as next-generation catalysts. The zirconia-gold system has received little attention due to the lack of controllable preparation methods. Well-known methods for the deposition of gold nanoshells on silica spheres, however, should be adaptable for similar zirconia-based materials. Here, we present a novel synthetic approach to the well-controlled deposition of gold on the surface of sol-gel derived zirconia mesoparticles by a stepwise method involving the immobilization of gold nanoparticles and repeated seeded-growth steps. We show that the immobilization efficiency is strongly enhanced by acidification with hydrochloric acid and additional employment of aminomethylphosphonic acid as coupling agent. The optimum conditions are identified and the subsequent incremental growth by seeded reduction of gold is demonstrated. The results shed light on the parameters governing the preparation of zirconia@gold composite particles and our synthetic approach provides a promising tool for future developments in complex nanomaterials design.
Collapse
|
15
|
Lacroix LM, Meffre A, Gatel C, Fazzini PF, Lachaize S, Respaud M, Chaudret B. Nanoparticle Ripening : A Versatile Approach for the Size and Shape Control of Metallic Iron Nanoparticles. Chempluschem 2020; 84:302-306. [PMID: 31950761 DOI: 10.1002/cplu.201800665] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/05/2019] [Indexed: 11/11/2022]
Abstract
A novel approach for the synthesis of Fe(0) nanoparticles (NPs) with tunable sizes and shapes is reported. Ultrasmall Fe(0) NPs were reacted under mild conditions in the presence of a mixture of palmitic acid and amine ligands. These NPs acted not only as preformed seeds but also as an internal iron(II) source that was produced by the partial dissolution of the NPs by the acid. This fairly simple approach allows the strict separation of the nucleation and the growth steps. By changing the acid concentration, a fine tuning of the relative ratio between the remaining Fe(0) seeds and the iron(II) reservoir was achieved, giving access to both size (from 7 to 20 nm) and shape (spheres, cubes or stars) control. The partial dissolution of the ultrasmall Fe(0) NPs into iron(II) source and the successive growth was further studied by using combined TEM and Mössbauer spectroscopy. The successive corrosion, coalescence, and ripening observed could be understood in the framework of an environment-dependent growth model.
Collapse
|
16
|
Andalibi MR, Wokaun A, Bowen P, Testino A. Kinetics and Mechanism of Metal Nanoparticle Growth via Optical Extinction Spectroscopy and Computational Modeling: The Curious Case of Colloidal Gold. ACS NANO 2019; 13:11510-11521. [PMID: 31483989 DOI: 10.1021/acsnano.9b04981] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
An overarching computational framework unifying several optical theories to describe the temporal evolution of gold nanoparticles (GNPs) during a seeded growth process is presented. To achieve this, we used the inexpensive and widely available optical extinction spectroscopy, to obtain quantitative kinetic data. In situ spectra collected over a wide set of experimental conditions were regressed using the physical model, calculating light extinction by ensembles of GNPs during the growth process. This model provides temporal information on the size, shape, and concentration of the particles and any electromagnetic interactions between them. Consequently, we were able to describe the mechanism of GNP growth and divide the process into distinct genesis periods. We provide explanations for several longstanding mysteries, for example, the phenomena responsible for the purple-greyish hue during the early stages of GNP growth, the complex interactions between nucleation, growth, and aggregation events, and a clear distinction between agglomeration and electromagnetic interactions. The presented theoretical formalism has been developed in a generic fashion so that it can readily be adapted to other nanoparticulate formation scenarios such as the genesis of various metal nanoparticles.
Collapse
|
17
|
González-Rubio G, Kumar V, Llombart P, Díaz-Núñez P, Bladt E, Altantzis T, Bals S, Peña-Rodríguez O, Noya EG, MacDowell LG, Guerrero-Martínez A, Liz-Marzán LM. Disconnecting Symmetry Breaking from Seeded Growth for the Reproducible Synthesis of High Quality Gold Nanorods. ACS NANO 2019; 13:4424-4435. [PMID: 30939242 DOI: 10.1021/acsnano.8b09658] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
One of the major difficulties hindering the widespread application of colloidal anisotropic plasmonic nanoparticles is the limited robustness and reproducibility of multistep synthetic methods. We demonstrate herein that the reproducibility and reliability of colloidal gold nanorod (AuNR) synthesis can be greatly improved by disconnecting the symmetry-breaking event from the seeded growth process. We have used a modified silver-assisted seeded growth method in the presence of the surfactant hexadecyltrimethylammonium bromide and n-decanol as a co-surfactant to prepare small AuNRs in high yield, which were then used as seeds for the growth of high quality AuNR colloids. Whereas the use of n-decanol provides a more-rigid micellar system, the growth on anisotropic seeds avoids sources of irreproducibility during the symmetry breaking step, yielding uniform AuNR colloids with narrow plasmon bands, ranging from 600 to 1270 nm, and allowing the fine-tuning of the final dimensions. This method provides a robust route for the preparation of high quality AuNR colloids with tunable morphology, size, and optical response in a reproducible and scalable manner.
Collapse
|
18
|
Ye J, Helmi S, Teske J, Seidel R. Fabrication of Metal Nanostructures with Programmable Length and Patterns Using a Modular DNA Platform. NANO LETTERS 2019; 19:2707-2714. [PMID: 30887810 DOI: 10.1021/acs.nanolett.9b00740] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Recently introduced DNA nanomolds allow the shape-controlled growth of metallic nanoparticles. Here we demonstrate that this approach can be used to fabricate longer linear metal nanostructures of controlled lengths and patterns. To this end, we establish a set of different interfaces that enable mold interactions with high affinity and specificity. These interfaces enable and control the modular assembly of mold monomers into larger mold superstructure with programmable dimension in which each mold monomer remains uniquely addressable. Preloading the molds with nanoparticle seeds subsequently allows the growth of linear gold nanostructures whose lengths are controlled by the DNA structure. Exploiting the addressability of individual mold monomers furthermore allows achievement of site-specific metallization, that is, to create defined metal patterns. We think that the introduced approach provides a useful basis to fabricate nanomaterials with complex shapes and material composition in a fully programmable and modular fashion.
Collapse
|
19
|
Capitani C, Pinchetti V, Gariano G, Santiago-González B, Santambrogio C, Campione M, Prato M, Brescia R, Camellini A, Bellato F, Carulli F, Anand A, Zavelani-Rossi M, Meinardi F, Crooker SA, Brovelli S. Quantized Electronic Doping towards Atomically Controlled "Charge-Engineered" Semiconductor Nanocrystals. NANO LETTERS 2019; 19:1307-1317. [PMID: 30663314 DOI: 10.1021/acs.nanolett.8b04904] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
"Charge engineering" of semiconductor nanocrystals (NCs) through so-called electronic impurity doping is a long-standing challenge in colloidal chemistry and holds promise for ground-breaking advancements in many optoelectronic, photonic, and spin-based nanotechnologies. To date, our knowledge is limited to a few paradigmatic studies on a small number of model compounds and doping conditions, with important electronic dopants still unexplored in nanoscale systems. Equally importantly, fine-tuning of charge engineered NCs is hampered by the statistical limitations of traditional approaches. The resulting intrinsic doping inhomogeneity restricts fundamental studies to statistically averaged behaviors and complicates the realization of advanced device concepts based on their advantageous functionalities. Here we aim to address these issues by realizing the first example of II-VI NCs electronically doped with an exact number of heterovalent gold atoms, a known p-type acceptor impurity in bulk chalcogenides. Single-dopant accuracy across entire NC ensembles is obtained through a novel non-injection synthesis employing ligand-exchanged gold clusters as "quantized" dopant sources to seed the nucleation of CdSe NCs in organic media. Structural, spectroscopic, and magneto-optical investigations trace a comprehensive picture of the physical processes resulting from the exact doping level of the NCs. Gold atoms, doped here for the first time into II-VI NCs, are found to incorporate as nonmagnetic Au+ species activating intense size-tunable intragap photoluminescence and artificially offsetting the hole occupancy of valence band states. Fundamentally, the transient conversion of Au+ to paramagnetic Au2+ (5d9 configuration) under optical excitation results in strong photoinduced magnetism and diluted magnetic semiconductor behavior revealing the contribution of individual paramagnetic impurities to the macroscopic magnetism of the NCs. Altogether, our results demonstrate a new chemical approach toward NCs with physical functionalities tailored to the single impurity level and offer a versatile platform for future investigations and device exploitation of individual and collective impurity processes in quantum confined structures.
Collapse
|
20
|
Chen J, Feng J, Li Z, Xu P, Wang X, Yin W, Wang M, Ge X, Yin Y. Space-Confined Seeded Growth of Black Silver Nanostructures for Solar Steam Generation. NANO LETTERS 2019; 19:400-407. [PMID: 30561210 DOI: 10.1021/acs.nanolett.8b04157] [Citation(s) in RCA: 75] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Plasmonic metal nanostructures have attracted considerable attention for solar energy harvesting due to their capability in photothermal conversion. However, the narrow resonant band of the conventional plasmonic nanoparticles greatly limits their application as only a small fraction of the solar energy can be utilized. Herein, a unique confined seeded growth strategy is developed to synthesize black silver nanostructures with broadband absorption in the visible and near-infrared spectrum. Through this novel strategy, assemblages of silver nanoparticles with widely distributed interparticle distances are generated in rod-shaped tubular spaces, leading to strong random plasmonic coupling and accordingly broadband absorption for significantly improved utilization of solar energy. With excellent efficiency in converting solar energy to heat, the resulting black Ag nanostructures can be made into thin films floating at the air/water interface for efficient generation of clean water steam through localized interfacial heating.
Collapse
|
21
|
Bayrak T, Helmi S, Ye J, Kauert D, Kelling J, Schönherr T, Weichelt R, Erbe A, Seidel R. DNA-Mold Templated Assembly of Conductive Gold Nanowires. NANO LETTERS 2018; 18:2116-2123. [PMID: 29482327 DOI: 10.1021/acs.nanolett.8b00344] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We introduce a new concept for the solution-based fabrication of conductive gold nanowires using DNA templates. To this end, we employ DNA nanomolds, inside which electroless gold deposition is initiated by site-specific attached seeds. Using programmable interfaces, individual molds self-assemble into micrometer-long mold superstructures. During subsequent internal gold deposition, the mold walls constrain the metal growth, such that highly homogeneous nanowires with 20-30 nm diameters are obtained. Wire contacting using electron-beam lithography and electrical conductance characterization at temperatures between 4.2 K and room temperature demonstrate that metallic conducting wires were produced, although for part of the wires, the conductance is limited by boundaries between gold grains. Using different mold designs, our synthesis scheme will, in the future, allow the fabrication of complex metal structures with programmable shapes.
Collapse
|
22
|
Yau WM, Tycko R. Depletion of amyloid-β peptides from solution by sequestration within fibril-seeded hydrogels. Protein Sci 2018; 27:1218-1230. [PMID: 29417648 DOI: 10.1002/pro.3387] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 02/02/2018] [Accepted: 02/05/2018] [Indexed: 11/10/2022]
Abstract
Aggregation of amyloid-β (Aβ) peptides in brain tissue leads to neurodegeneration in Alzheimer's disease (AD). Regardless of the kinetics or detailed mechanisms of Aβ aggregation, aggregation can only occur if Aβ concentrations exceed their local equilibrium solubility values. We propose that excess Aβ peptides can be removed from supersaturated solutions, including solutions in biological fluids, by the addition of hydrogels that are seeded with Aβ fibril fragments. Fibril growth within the hydrogels then sequesters excess peptides until equilibrium concentrations are reached. Experiments with 40- and 42-residue Aβ peptides (Aβ40 and Aβ42) in phosphate buffer at 24°C and in filtered fetal bovine serum at 37°C, using crosslinked polyacrylamide hydrogels, demonstrate the validity of this concept. Aβ sequestration in fibril-seeded hydrogels (or other porous media) may prove to be a useful technique in experiments with animal models of AD and may represent a possible approach to preventing or slowing the progression of AD in humans.
Collapse
|
23
|
Robinson ME, Nazemi A, Lunn DJ, Hayward DW, Boott CE, Hsiao MS, Harniman RL, Davis SA, Whittell GR, Richardson RM, De Cola L, Manners I. Dimensional Control and Morphological Transformations of Supramolecular Polymeric Nanofibers Based on Cofacially-Stacked Planar Amphiphilic Platinum(II) Complexes. ACS NANO 2017; 11:9162-9175. [PMID: 28836765 DOI: 10.1021/acsnano.7b04069] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Square-planar platinum(II) complexes often stack cofacially to yield supramolecular fiber-like structures with interesting photophysical properties. However, control over fiber dimensions and the resulting colloidal stability is limited. We report the self-assembly of amphiphilic Pt(II) complexes with solubilizing ancillary ligands based on polyethylene glycol [PEGn, where n = 16, 12, 7]. The complex with the longest solubilizing PEG ligand, Pt-PEG16, self-assembled to form polydisperse one-dimensional (1D) nanofibers (diameters <5 nm). Sonication led to short seeds which, on addition of further molecularly dissolved Pt-PEG16 complex, underwent elongation in a "living supramolecular polymerization" process to yield relatively uniform fibers of length up to ca. 400 nm. The fiber lengths were dependent on the Pt-PEG16 complex to seed mass ratio in a manner analogous to a living covalent polymerization of molecular monomers. Moreover, the fiber lengths were unchanged in solution after 1 week and were therefore "static" with respect to interfiber exchange processes on this time scale. In contrast, similarly formed near-uniform fibers of Pt-PEG12 exhibited dynamic behavior that led to broadening of the length distribution within 48 h. After aging for 4 weeks in solution, Pt-PEG12 fibers partially evolved into 2D platelets. Furthermore, self-assembly of Pt-PEG7 yielded only transient fibers which rapidly evolved into 2D platelets. On addition of further fiber-forming Pt complex (Pt-PEG16), the platelets formed assemblies via the growth of fibers selectively from their short edges. Our studies demonstrate that when interfiber dynamic exchange is suppressed, dimensional control and hierarchical structure formation are possible for supramolecular polymers through the use of kinetically controlled seeded growth methods.
Collapse
|
24
|
Gao Z, Ye H, Tang D, Tao J, Habibi S, Minerick A, Tang D, Xia X. Platinum-Decorated Gold Nanoparticles with Dual Functionalities for Ultrasensitive Colorimetric in Vitro Diagnostics. NANO LETTERS 2017; 17:5572-5579. [PMID: 28813601 DOI: 10.1021/acs.nanolett.7b02385] [Citation(s) in RCA: 184] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Au nanoparticles (AuNPs) as signal reporters have been utilized in colorimetric in vitro diagnostics (IVDs) for decades. Nevertheless, it remains a grand challenge to substantially enhance the detection sensitivity of AuNP-based IVDs as confined by the inherent plasmonics of AuNPs. In this work, we circumvent this confinement by developing unique dual-functional AuNPs that were engineered by coating conventional AuNPs with ultrathin Pt skins of sub-10 atomic layers (i.e., Au@Pt NPs). The Au@Pt NPs retain the plasmonic activity of initial AuNPs while possessing ultrahigh catalytic activity enabled by Pt skins. Such dual functionalities, plasmonics and catalysis, offer two different detection alternatives: one produced just by the color from plasmonics (low-sensitivity mode) and the second more sensitive color catalyzed from chromogenic substrates (high-sensitivity mode), achieving an "on-demand" tuning of the detection performance. Using lateral flow assay as a model IVD platform and conventional AuNPs as a benchmark, we demonstrate that the Au@Pt NPs could enhance detection sensitivity by 2 orders of magnitude.
Collapse
|
25
|
Wang C, Sang X, Gamler JTL, Chen DP, Unocic RR, Skrabalak SE. Facet-Dependent Deposition of Highly Strained Alloyed Shells on Intermetallic Nanoparticles for Enhanced Electrocatalysis. NANO LETTERS 2017; 17:5526-5532. [PMID: 28840730 DOI: 10.1021/acs.nanolett.7b02239] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Surface strains can enhance the performance of platinum-based core@shell electrocatalysts for the oxygen reduction reaction (ORR). Bimetallic core@shell nanoparticles (NPs) are widely studied nanocatalysts but often have limited lattice mismatch and surface compositions; investigations of core@shell NPs with greater compositional complexity and lattice misfit are in their infancy. Here, a new class of multimetallic NPs composed of intermetallic cores and random alloy shells is reported. Specifically, face-centered cubic Pt-Cu random alloy shells were deposited on PdCu B2 intermetallic seeds in a facet-dependent manner, giving rise to faceted core@shell NPs with highly strained surfaces. High-resolution transmission electron microscopy revealed orientation-dependent surface strains, where the compressive strains were greater on Pt-Cu {200} than {111} facets. These core@shell NPs provide higher specific area and mass activities for the ORR when compared to conventional Pt-Cu NPs. Moreover, these intermetallic@random alloy NPs displayed high endurance, undergoing 10,000 cycles with only a slight decay in activity and no apparent structural changes.
Collapse
|