1
|
Bhowmick M, Christensen J, Adjorlolo R, Ullrich B. Photoluminescence from Two-Phase Nanocomposites Embedded in Polymers. MICROMACHINES 2024; 15:111. [PMID: 38258230 PMCID: PMC10820105 DOI: 10.3390/mi15010111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 01/01/2024] [Accepted: 01/05/2024] [Indexed: 01/24/2024]
Abstract
A set of polymer-embedded, two-colored nanocomposites were prepared where the co-existing emission peaks (~578 nm and ~650 nm) had different ratios at their emission thresholds. The nanocomposite samples were simultaneously excited by a 405 nm laser, and the growth of photoluminescence intensities was studied as a function of excitation intensity. The two peaks showed different growth evolution mechanisms. The factors impacting this difference could be (1) energy transfer between the two sized nanoparticles; (2) relaxation mechanism of smaller nanoparticles; and (3) material properties of the polymer.
Collapse
Affiliation(s)
- Mithun Bhowmick
- Mathematical and Physical Sciences, Miami University Regionals, Middletown, OH 45042, USA
| | - James Christensen
- Construction Engineering Research Laboratory, United States Army Corps of Engineers, Champaign, IL 61822, USA
| | - Richard Adjorlolo
- Mathematical and Physical Sciences, Miami University Regionals, Middletown, OH 45042, USA
| | | |
Collapse
|
2
|
Wang J, Wang L, Su X, Gao D, Yu H. CdTe quantum dot-based self-supporting films with enhanced stability for flexible light-emitting devices. SOFT MATTER 2022; 18:7324-7332. [PMID: 36111894 DOI: 10.1039/d2sm01108e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The enhancement of photoluminescence (PL) stability of colloidal quantum dots (CQDs) is of great significance in light-emitting devices. In this work, the PL stability of CdTe CQDs under time storage, strong light irradiation, acid and alkali corrosion and low temperature freezing is analyzed, and the PL quenching mechanism in a harsh environment is analyzed. Furthermore, the PL stability is extremely improved by core-shell coating, film deposition and polymer encapsulation. This solves the problem of rapid dropping of the PL intensity at the initial illumination stage and improves the corrosion resistance in an acidic environment and long-term storage stability of film devices. CQD polymer films have an interesting phenomenon of fluorescence enhancement under illumination due to the light-soaking effect. Biocompatible coating and encapsulation materials expand the application of CQD devices in the field of biological tissue imaging and sensing. Through the PL regulation of CQD solutions and the simple superposition of self-supporting films, a panchromatic light-emitting device with broadband adjustable chromaticity is realized. The solid-state stable whispering-gallery-mode (WGM) laser is realized by monodisperse SiO2 microspheres embedded in the film. This work is of great significance for the application of CQDs in flexible light-emitting devices.
Collapse
Affiliation(s)
- Jin Wang
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing, 100124, China.
| | - Li Wang
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing, 100124, China.
| | - Xueqiong Su
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing, 100124, China.
| | - Dongwen Gao
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing, 100124, China.
| | - Huimin Yu
- College of Physics and Optoelectronics, Faculty of Science, Beijing University of Technology, Beijing, 100124, China.
| |
Collapse
|
3
|
Singhal J, Verma S, Kumar S, Mehrotra D. Recent Advances in Nano-Bio-Sensing Fabrication Technology for the Detection of Oral Cancer. Mol Biotechnol 2021; 63:339-362. [PMID: 33638110 DOI: 10.1007/s12033-021-00306-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/06/2021] [Indexed: 12/24/2022]
Abstract
Nanotechnology-based miniaturized devices have been a breakthrough in the pre-clinical and clinical research areas, e.g. drug delivery, personalized medicine. They have revolutionized the discovery and development of biomarker-based diagnostic devices for detection of various diseases such as tuberculosis, malaria and cancer. Nanomaterials (NMs) hold tremendous diagnostic potential due to their high surface-to-volume ratio and quantum confinement phenomenon, improving the detection limit of clinically relevant biomolecules in bio-fluids. Thus, they are helpful in the translation of bench-on platform to point-of-care (POC) screening device. The nanomaterial-based biosensor fabrication technology has also simplified and improved oral cancer (OC) or oral squamous cell carcinomas (OSCC) diagnosis. The fabrication of nano-bio sensors involves application specific modifications of NMs. The unique properties functionalized NMs have augmented their application on the nano-biosensing platform for the detection of clinically relevant biomolecules in bio-fluids. Therefore, this article summarizes the recent advancements in the process of fabrication of nano-biosensors for detection of OC.
Collapse
Affiliation(s)
- Jaya Singhal
- Department of Health Research - Multidisciplinary Research Unit, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India.,Department of Oral and Maxillofacial Surgery, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India
| | - Saurabh Verma
- Department of Health Research - Multidisciplinary Research Unit, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India
| | - Sumit Kumar
- Department of Health Research - Multidisciplinary Research Unit, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India.
| | - Divya Mehrotra
- Department of Health Research - Multidisciplinary Research Unit, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India. .,Department of Oral and Maxillofacial Surgery, King George's Medical University, Lucknow, 226003, Uttar Pradesh, India.
| |
Collapse
|
4
|
Phase transfer reaction for the preparation of stable polymer-quantum dot conjugates. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2018.10.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
5
|
Jung J, Lin CH, Yoon YJ, Malak ST, Zhai Y, Thomas EL, Vardeny V, Tsukruk VV, Lin Z. Crafting Core/Graded Shell-Shell Quantum Dots with Suppressed Re-absorption and Tunable Stokes Shift as High Optical Gain Materials. Angew Chem Int Ed Engl 2016; 55:5071-5. [DOI: 10.1002/anie.201601198] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Indexed: 11/06/2022]
Affiliation(s)
- Jaehan Jung
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Chun Hao Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Young Jun Yoon
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Sidney T. Malak
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Yaxin Zhai
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Edwin L. Thomas
- Department of Materials Science and Nanoengineering; Rice University; Houston TX 77251 USA
| | - Valy Vardeny
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Zhiqun Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| |
Collapse
|
6
|
Jung J, Lin CH, Yoon YJ, Malak ST, Zhai Y, Thomas EL, Vardeny V, Tsukruk VV, Lin Z. Crafting Core/Graded Shell-Shell Quantum Dots with Suppressed Re-absorption and Tunable Stokes Shift as High Optical Gain Materials. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jaehan Jung
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Chun Hao Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Young Jun Yoon
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Sidney T. Malak
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Yaxin Zhai
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Edwin L. Thomas
- Department of Materials Science and Nanoengineering; Rice University; Houston TX 77251 USA
| | - Valy Vardeny
- Department of Physics and Astronomy; University of Utah; Salt Lake City UT 84112 USA
| | - Vladimir V. Tsukruk
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| | - Zhiqun Lin
- School of Materials Science and Engineering; Georgia Institute of Technology; Atlanta GA 30332 USA
| |
Collapse
|
7
|
Thin polymer films grafted to the solid surface with in situ synthesized CdS nanocrystals. JOURNAL OF POLYMER RESEARCH 2015. [DOI: 10.1007/s10965-015-0807-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
8
|
|
9
|
Yokota H, Taniguchi T, Watanabe T, Kim D. Control of localized surface plasmon resonance energy in monolayer structures of gold and silver nanoparticles. Phys Chem Chem Phys 2015; 17:27077-81. [DOI: 10.1039/c5cp03928b] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The LSPR energy was successfully controlled in the wide range of 2.0–3.0 eV using Au and Ag nanoparticles.
Collapse
Affiliation(s)
- Hiroki Yokota
- Department of Applied Physics
- Graduate School of Engineering
- Osaka City University
- Sumiyoshi-ku
- Japan
| | - Taichi Taniguchi
- Department of Applied Physics
- Graduate School of Engineering
- Osaka City University
- Sumiyoshi-ku
- Japan
| | - Taichi Watanabe
- Department of Applied Physics
- Graduate School of Engineering
- Osaka City University
- Sumiyoshi-ku
- Japan
| | - DaeGwi Kim
- Department of Applied Physics
- Graduate School of Engineering
- Osaka City University
- Sumiyoshi-ku
- Japan
| |
Collapse
|
10
|
Patty K, Sadeghi SM, Campbell Q, Hamilton N, West RG, Mao C. Probing the structural dependency of photoinduced properties of colloidal quantum dots using metal-oxide photo-active substrates. JOURNAL OF APPLIED PHYSICS 2014; 116:114301. [PMID: 25316953 PMCID: PMC4187343 DOI: 10.1063/1.4894445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 08/21/2014] [Indexed: 06/04/2023]
Abstract
We used photoactive substrates consisting of about 1 nm coating of a metal oxide on glass substrates to investigate the impact of the structures of colloidal quantum dots on their photophysical and photochemical properties. We showed during irradiation these substrates can interact uniquely with such quantum dots, inducing distinct forms of photo-induced processes when they have different cores, shells, or ligands. In particular, our results showed that for certain types of core-shell quantum dot structures an ultrathin layer of a metal oxide can reduce suppression of quantum efficiency of the quantum dots happening when they undergo extensive photo-oxidation. This suggests the possibility of shrinking the sizes of quantum dots without significant enhancement of their non-radiative decay rates. We show that such quantum dots are not influenced significantly by Coulomb blockade or photoionization, while those without a shell can undergo a large amount of photo-induced fluorescence enhancement via such blockade when they are in touch with the metal oxide.
Collapse
Affiliation(s)
- Kira Patty
- Department of Physics, University of Alabama in Huntsville , Huntsville, Alabama 35899, USA
| | | | - Quinn Campbell
- Department of Physics, University of Alabama in Huntsville , Huntsville, Alabama 35899, USA
| | - Nathan Hamilton
- Department of Physics, University of Alabama in Huntsville , Huntsville, Alabama 35899, USA
| | - Robert G West
- Department of Physics, University of Alabama in Huntsville , Huntsville, Alabama 35899, USA
| | - Chuanbin Mao
- Department of Chemistry and Biochemistry, Stephenson Life Sciences Research Center, University of Oklahoma , Norman, Oklahoma 73019, USA
| |
Collapse
|
11
|
Das S, Satpati B, Chauhan H, Deka S, Gopinath CS, Bala T. Preferential growth of Au on CdSe quantum dots using Langmuir–Blodgett technique. RSC Adv 2014. [DOI: 10.1039/c4ra11715h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Oleyl amine capped CdSe quantum dots are allowed to form monolayer on aqueous HAuCl4 subphase and Langmuir–Blodgett technique is used judicially to grow Au tips in a directed fashion on CdSe quantum dots.
Collapse
Affiliation(s)
- Subhasis Das
- Department of Chemistry and Centre for Research in Nanoscience and Nanotechnology (CRNN)
- University of Calcutta
- Kolkata-700009, India
| | - Biswarup Satpati
- Surface Physics and Material Science Division
- Saha Institute of Nuclear Physics
- Kolkata-64, India
| | - Himani Chauhan
- Department of Chemistry
- University of Delhi
- New Delhi-110007, India
| | - Sasanka Deka
- Department of Chemistry
- University of Delhi
- New Delhi-110007, India
| | - Chinnakonda S. Gopinath
- Catalysis Division and Center of Excellence on Surface Science
- CSIR – National Chemical Laboratory
- Pune-411 008, India
| | - Tanushree Bala
- Department of Chemistry and Centre for Research in Nanoscience and Nanotechnology (CRNN)
- University of Calcutta
- Kolkata-700009, India
| |
Collapse
|
12
|
Zhao L, Lin Z. Crafting semiconductor organic-inorganic nanocomposites via placing conjugated polymers in intimate contact with nanocrystals for hybrid solar cells. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2012; 24:4353-4368. [PMID: 22761026 DOI: 10.1002/adma.201201196] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2012] [Indexed: 06/01/2023]
Abstract
Semiconductor organic-inorganic hybrid solar cells incorporating conjugated polymers (CPs) and nanocrystals (NCs) offer the potential to deliver efficient energy conversion with low-cost fabrication. The CP-based photovoltaic devices are complimented by an extensive set of advantageous characteristics from CPs and NCs, such as lightweight, flexibility, and solution-processability of CPs, combined with high electron mobility and size-dependent optical properties of NCs. Recent research has witnessed rapid advances in an emerging field of directly tethering CPs on the NC surface to yield an intimately contacted CP-NC nanocomposite possessing a well-defined interface that markedly promotes the dispersion of NCs within the CP matrix, facilitates the photoinduced charge transfer between these two semiconductor components, and provides an effective platform for studying the interfacial charge separation and transport. In this Review, we aim to highlight the recent developments in CP-NC nanocomposite materials, critically examine the viable preparative strategies geared to craft intimate CP-NC nanocomposites and their photovoltaic performance in hybrid solar cells, and finally provide an outlook for future directions of this extraordinarily rich field.
Collapse
Affiliation(s)
- Lei Zhao
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | | |
Collapse
|
13
|
Han W, Lin Z. Von “Kaffeeringen” lernen: geordnete Strukturen durch Selbstorganisation bei kontrollierter Verdunstung. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104454] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
14
|
Han W, Lin Z. Learning from “Coffee Rings”: Ordered Structures Enabled by Controlled Evaporative Self-Assembly. Angew Chem Int Ed Engl 2011; 51:1534-46. [DOI: 10.1002/anie.201104454] [Citation(s) in RCA: 371] [Impact Index Per Article: 28.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Indexed: 11/05/2022]
|
15
|
Chung JY, Nolte AJ, Stafford CM. Surface wrinkling: a versatile platform for measuring thin-film properties. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2011; 23:349-68. [PMID: 20814918 DOI: 10.1002/adma.201001759] [Citation(s) in RCA: 268] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Indexed: 05/04/2023]
Abstract
Surface instabilities in soft matter have been the subject of increasingly innovative research aimed at better understanding the physics of their formation and their utility in patterning, organizing, and measuring materials properties on the micro and nanoscale. The focus of this Review is on a type of instability pattern known as surface wrinkling, covering the general concepts of this phenomenon and several recent applications involving the measurement of thin-film properties. The ability of surface wrinkling to yield new insights into particularly challenging materials systems such as ultrathin films, polymer brushes, polyelectrolyte multilayer assemblies, ultrasoft materials, and nanoscale structured materials is highlighted. A perspective on the future directions of this maturing field, including the prospects for advanced thin-film metrology methods, facile surface patterning, and the control of topology-sensitive phenomena, such as wetting and adhesion, is also presented.
Collapse
Affiliation(s)
- Jun Young Chung
- Polymers Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA
| | | | | |
Collapse
|
16
|
Brito WH, Silva RA, Miwa RH. Gold adatoms and clusters on PPV: An ab initio investigation. J Chem Phys 2010; 133:204703. [PMID: 21133448 DOI: 10.1063/1.3506771] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have performed an ab initio investigation of the energetic, structural, electronic, and vibrational properties of Au atoms and clusters adsorbed on poly-p-phenylene vinylene (PPV) chains, Au(n)/PPV (with n = 1, 2, 6, 7, 10, and 12). We find that the Au(n)/PPV systems are energetically stable by 0.5 eV, compared with the isolated systems, viz., PPV chain and Au(n) clusters, thus supporting the formation of Au(n)/PPV nanocomposites. Further support to the formation of Au(n)/PPV has been provided by examining the vibrational properties of pristine PPV and Au(n)/PPV systems. In agreement with experimental measurements, we find a reduction on the in-plane vibrational frequency of C-C bonds of Au(n)/PPV, when compared with the same vibrational modes of pristine PPV. The electronic properties of isolated Au(n) clusters are modified when adsorbed on PPV. The highest occupied states of Au(n)/PPV are mostly concentrated on the Au(n) cluster, while the lowest unoccupied states are mainly localized along the PPV chain. The HOMO-LUMO energy gap of the Au(n)/PPV systems are smaller than the energy gap of the isolated systems, Au(n) clusters, and pristime PPV chains.
Collapse
Affiliation(s)
- W H Brito
- Instituto de Física, Universidade Federal de Uberlândia, C. P. 593, 38400-902 Uberlândia, MG, Brazil
| | | | | |
Collapse
|
17
|
Rauf S, Glidle A, Cooper JM. Layer-by-layer quantum dot constructs using self-assembly methods. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:16934-16940. [PMID: 20936803 DOI: 10.1021/la103385s] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We describe the creation of CdSe/ZnS quantum dot assemblies using layer-by-layer construction strategies, using self-assembly. In the first approach, a dithiol linker was used to make multilayers of CdSe/ZnS quantum dots, while in the second biotin- and streptavidin-conjugated CdSe/ZnS quantum dots were used to make multilayer constructs. Both the chemical bonding nature and fluorescence spectroscopic properties of quantum dot films were characterized using X-ray photoelectron spectroscopy (XPS) and fluorescence spectroscopy.
Collapse
Affiliation(s)
- Sakandar Rauf
- Department of Electronics and Electrical Engineering, Oakfield Avenue, University of Glasgow, UK G12 8LT.
| | | | | |
Collapse
|
18
|
Zhou ZK, Li M, Yang ZJ, Peng XN, Su XR, Zhang ZS, Li JB, Kim NC, Yu XF, Zhou L, Hao ZH, Wang QQ. Plasmon-mediated radiative energy transfer across a silver nanowire array via resonant transmission and subwavelength imaging. ACS NANO 2010; 4:5003-5010. [PMID: 20738124 DOI: 10.1021/nn100578b] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Efficient plasmon-mediated excitation energy transfer between the CdSe/ZnS semiconductor quantum dots (QDs) across the silver nanowire array up to 560 nm in length is observed. The subwavelength imaging and spectral response of the silver nanowire arrays with near-field point-source excitations are revealed by theoretical simulations. Our studies demonstrate three advantages of the nanosystem: efficient exciton-plasmon conversion at the input side of the array through near-field strong coupling, directional waveguidance and resonant transmission via half-wave plasmon modes of the nanowire array, and subwavelength imaging at the output side of the array. These advantages allow a long-range radiative excitation energy transfer with a high efficiency and a good directionality.
Collapse
Affiliation(s)
- Zhang-Kai Zhou
- Department of Physics, Key Laboratory of Acoustic and Photonic Materials and Devices of Ministry of Education, Wuhan University, Wuhan 430072, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
19
|
Chan YH, Chen J, Liu Q, Wark SE, Son DH, Batteas JD. Ultrasensitive copper(II) detection using plasmon-enhanced and photo-brightened luminescence of CdSe quantum dots. Anal Chem 2010; 82:3671-8. [PMID: 20377191 DOI: 10.1021/ac902985p] [Citation(s) in RCA: 178] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Here, we present a simple platform for the use of the enhanced emission of 16-mercaptohexadecanoic acid (16-MHA) capped CdSe quantum dots (QDs) as a probe for ultrasensitive copper(II) detection. In this study, the photoluminescence (PL) of the QDs was first enhanced by Ag nanoprisms which were self-assembled on Si surfaces and then further increased by photobrightening. Using this approach, the control and different analytes could be readily probed all on a single platform using fluorescence microscopy. The enhanced PL intensity of CdSe QDs was selectively quenched in the presence of Cu(2+), accompanied by the emergence of a new red-shifted luminescence band. The quenching mechanism was found to be due to a cation exchange mechanism as confirmed by X-ray photoelectron spectroscopy (XPS) measurements. Herein, we have demonstrated that this simple methodology can offer a rapid and reliable detection of Cu(2+) with a detection limit as low as 5 nM and a dynamic range up to 100 muM in a fixed fast reaction time of 5 min. The potential applications of this technique were tested in two ways, for mixed-ion solutions and in physiological fluids, and both experiments exhibited good selectivity toward Cu(2+).
Collapse
Affiliation(s)
- Yang-Hsiang Chan
- Department of Chemistry, Texas A&M University, PO Box 30012, College Station, Texas 77842-3012, USA
| | | | | | | | | | | |
Collapse
|
20
|
Lambert K, Capek RK, Bodnarchuk MI, Kovalenko MV, Van Thourhout D, Heiss W, Hens Z. Langmuir-Schaefer deposition of quantum dot multilayers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:7732-6. [PMID: 20121263 DOI: 10.1021/la904474h] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The application of colloidal nanocrystals in various devices requires their assembly into well-defined mono- or multilayers. We explore the possibilities of the Langmuir-Schaefer technique to make such layers, using CdSe quantum dots as a model system. The layer quality is assessed using atomic force microscopy, transmission electron microscopy, and UV-vis absorption spectroscopy. For hydrophobic substrates, we find that the Langmuir-Schaefer technique is an excellent tool for controlled multilayer production. With hydrophilic substrates, dewetting induces a cellular superstructure. Combination with photolithography leads to micropatterned multilayers, and combination of different nanocrystal sizes allows for the formation of 2D binary superstructures.
Collapse
Affiliation(s)
- Karel Lambert
- Physics and Chemistry of Nanostructures, Ghent University, Krijgslaan 281-S3, 9000 Gent, Belgium
| | | | | | | | | | | | | |
Collapse
|
21
|
Kozlovskaya V, Kharlampieva E, Jones K, Lin Z, Tsukruk VV. pH-controlled assembly and properties of LbL membranes from branched conjugated poly(alkoxythiophene sulfonate) and various polycations. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:7138-7147. [PMID: 20000796 DOI: 10.1021/la9042099] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We report on multilayer layer-by-layer (LbL) films of the conjugated polymer sodium poly[2-(3-thienyl)ethyloxy-4-butylsulfonate] (PTH) assembled with polycations: poly(diallyldimethylammonium chloride) (PDDA), 20% quaternized poly(N-ethyl-4-vinylpyridinium bromide) (Q20), poly(ethylene imine) (PEI), and poly(allylamine hydrochloride) (PAH). These films were prepared through spin-assisted LbL assembly under various pH conditions. We demonstrated a crucial role of the deposition pH in formation of PTH/polycation films and showed that decrease in the deposition pH from 7.5 to 2.5 limits the PTH multilayer formation to Q20/PTH and PDDA/PTH films due to reduced charge density in the poly(thiophene) chains. We show that optical and surface properties of the resulting PTH/polycation films can be tuned by varying a polycation component and/or by varying the deposition pH. The fluorescence properties of the Q20/PTH, PEI/PTH, and PDDA/PTH films are pH-dependent, and the films exhibit the drastic changes in photoluminescent intensity when transferred into solutions with different pH values, which may find useful in optical sensing applications.
Collapse
Affiliation(s)
- Veronika Kozlovskaya
- School of Materials Science and Engineering , Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | | | | | | |
Collapse
|
22
|
Bao Y, Luu QAN, Lin C, Schloss JM, May PS, Jiang C. Layer-by-layer assembly of freestanding thin films with homogeneously distributed upconversion nanocrystals. ACTA ACUST UNITED AC 2010. [DOI: 10.1039/c0jm01602k] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
23
|
Cao L, Qu H, Sun D, Su G, Liu W, Sun Y. Solvothermal synthesis and luminescence properties of CdS:Mn nanorods. ACTA ACUST UNITED AC 2009. [DOI: 10.1007/s11426-009-0170-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
24
|
Chen J, Chan YH, Yang T, Wark SE, Son DH, Batteas JD. Spatially Selective Optical Tuning of Quantum Dot Thin Film Luminescence. J Am Chem Soc 2009; 131:18204-5. [DOI: 10.1021/ja906837s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jixin Chen
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| | - Yang-Hsiang Chan
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| | - Tinglu Yang
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| | - Stacey E. Wark
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| | - Dong Hee Son
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| | - James D. Batteas
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012
| |
Collapse
|
25
|
Influence of proton irradiation on the structure and stability of poly(dimethylsiloxane) and poly(dimethylsiloxane)-nanodiamond composite. ACTA ACUST UNITED AC 2009. [DOI: 10.1116/1.3258156] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
26
|
Wang J, Zhao L, Lin VSY, Lin Z. Formation of various TiO2 nanostructures from electrochemically anodized titanium. ACTA ACUST UNITED AC 2009. [DOI: 10.1039/b904247d] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
27
|
Zhang J, Li Q, Di X, Liu Z, Xu G. Layer-by-layer assembly of multicolored semiconductor quantum dots towards efficient blue, green, red and full color optical films. NANOTECHNOLOGY 2008; 19:435606. [PMID: 21832701 DOI: 10.1088/0957-4484/19/43/435606] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Multicolored semiconductor quantum dots have shown great promise for construction of miniaturized light-emitting diodes with compact size, low weight and cost, and high luminescent efficiency. The unique size-dependent luminescent property of quantum dots offers the feasibility of constructing single-color or full-color output light-emitting diodes with one type of material. In this paper, we have demonstrated the facile fabrication of blue-, green-, red- and full-color-emitting semiconductor quantum dot optical films via a layer-by-layer assembly technique. The optical films were constructed by alternative deposition of different colored quantum dots with a series of oppositely charged species, in particular, the new use of cationic starch on glass substrates. Semiconductor ZnSe quantum dots exhibiting blue emission were deposited for fabrication of blue-emitting optical films, while semiconductor CdTe quantum dots with green and red emission were utilized for construction of green- and red-emitting optical films. The assembly of integrated blue, green and red semiconductor quantum dots resulted in full-color-emitting optical films. The luminescent optical films showed very bright emitting colors under UV irradiation, and displayed dense, smooth and efficient luminous features, showing brighter luminescence in comparison with their corresponding quantum dot aqueous colloid solutions. The assembled optical films provide the prospect of miniaturized light-emitting-diode applications.
Collapse
Affiliation(s)
- Jun Zhang
- College of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot, Inner Mongolia 010021, People's Republic of China. State Key Laboratory of Transducer Technology, Chinese Academy of Science, Shanghai 200050, People's Republic of China
| | | | | | | | | |
Collapse
|
28
|
Zimnitsky D, Shevchenko VV, Tsukruk VV. Perforated, freely suspended layer-by-layer nanoscale membranes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2008; 24:5996-6006. [PMID: 18457436 DOI: 10.1021/la7038575] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ultrathin, perforated, and freely suspended membranes with uniform nanopores in the range of tens of nanometers have been fabricated using a fast, simple method of spin-assisted layer-by-layer assembly on hydrophobic substrates. Membranes with thicknesses down to 20 nm were robust enough to be released from the sacrificial substrates, transferred onto various surfaces, and suspended over microscopic openings. The nanopore size can be controlled by tuning the number of polyelectrolyte bilayers, spinning speed, and a proper selection of hydrophobic substrates. We demonstrate that the formation of nanopores is caused by the partial dewetting of polyelectrolyte layers in the course of their deposition on the underlying hydrophobic surfaces. The nanoscale thickness of perforated membranes with relatively uniform size and a high concentration of nanopores provides perspectives for higher rates of transport through freely suspended LbL membranes. The highly perforated LbL membranes introduced here can serve as a novel platform for ultrafine separation considering an intriguing combination of nanopores, nanoscale membrane thickness, and easy functionalization.
Collapse
Affiliation(s)
- Dmitry Zimnitsky
- Georgia Institute of Technology, School of Materials Science and Engineering, Atlanta, Georgia 30332, USA
| | | | | |
Collapse
|
29
|
Zimnitsky D, Xu J, Lin Z, Tsukruk VV. Domain and network aggregation of CdTe quantum rods within Langmuir-Blodgett monolayers. NANOTECHNOLOGY 2008; 19:215606. [PMID: 21730579 DOI: 10.1088/0957-4484/19/21/215606] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Control over the organization of quantum rods was demonstrated by changing the surface area at the air-liquid interface by means of the Langmuir-Blodgett (LB) technique. The LB isotherm of CdTe quantum rods capped with a mixture of alkylphosphines shows a transition point in the liquid-solid state, which is caused by the inter-rod reorganization. As we observed, at low surface pressure the quantum rods are assembled into round-shaped aggregates composed of a monolayer of nanorods packed in limited-size clusters with random orientation. The increase of the surface pressure leads to the rearrangement of these aggregates into elongated bundles composed of uniformly oriented nanorod clusters. Further compression results in denser packing of nanorods aggregates and in the transformation of monolayered domains into a continuous network of locally ordered quantum rods.
Collapse
Affiliation(s)
- Dmitry Zimnitsky
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
| | | | | | | |
Collapse
|
30
|
Lin Z. Organic-Inorganic Nanohybrids through the Direct Tailoring of Semiconductor Nanocrystals with Conjugated Polymers. Chemistry 2008; 14:6294-301. [DOI: 10.1002/chem.200800078] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
31
|
Wang J, Xu J, Goodman MD, Chen Y, Cai M, Shinar J, Lin Z. A simple biphasic route to water soluble dithiocarbamate functionalized quantum dots. ACTA ACUST UNITED AC 2008. [DOI: 10.1039/b803618g] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
32
|
Xu J, Wang J, Mitchell M, Mukherjee P, Jeffries-El M, Petrich JW, Lin Z. Organic−Inorganic Nanocomposites via Directly Grafting Conjugated Polymers onto Quantum Dots. J Am Chem Soc 2007; 129:12828-33. [PMID: 17914821 DOI: 10.1021/ja074133x] [Citation(s) in RCA: 205] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Nanocomposites of poly(3-hexylthiophene)-cadmium selenide (P3HT-CdSe) were synthesized by directly grafting vinyl-terminated P3HT onto [(4-bromophenyl)methyl]dioctylphosphine oxide (DOPO-Br)-functionalized CdSe quantum dot (QD) surfaces via a mild palladium-catalyzed Heck coupling, thereby dispensing with the need for ligand exchange chemistry. The resulting P3HT-CdSe nanocomposites possess a well-defined interface, thus significantly promoting the dispersion of CdSe within the P3HT matrix and facilitating the electronic interaction between these two components. The photophysical properties of nanocomposites were found to differ from the conventional composites in which P3HT and CdSe QDs were physically mixed. Solid-state emission spectra of nanocomposites suggested the charge transfer from P3HT to CdSe QDs, while the energy transfer from 3.5 nm CdSe QD to P3HT was implicated in the P3HT/CdSe composites. A faster decay in lifetime further confirmed the occurrence of charge transfer in P3HT-CdSe nanocomposites.
Collapse
Affiliation(s)
- Jun Xu
- Department of Materials Science and Engineering, Iowa State University, Ames, IA 50011, USA
| | | | | | | | | | | | | |
Collapse
|
33
|
Zimnitsky D, Jiang C, Xu J, Lin Z, Zhang L, Tsukruk VV. Photoluminescence of a freely suspended monolayer of quantum dots encapsulated into layer-by-layer films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2007; 23:10176-83. [PMID: 17725371 DOI: 10.1021/la7014644] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
A single monolayer of CdSe/ZnS quantum dots (QDs) has been encapsulated into a 60 nm free-suspended layer-by-layer (LbL) film. The QD monolayer showed a low light-emission within this film in contact with supporting solid substrates, but the manifold increase of photoluminescencence intensity was observed when the film was lifted and freely suspended over the microfabricated cylindrical cavities. This phenomenon was discussed in relationship with the effect of the elimination of the surface quenching enhanced by optical reflection from highly reflective silicon cavities. We suggest that a significant increase of the photoluminescence intensity of QD monolayers suspended over the microfabricated array can be interesting for future diagnostic and sensing applications.
Collapse
Affiliation(s)
- Dmitry Zimnitsky
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, USA
| | | | | | | | | | | |
Collapse
|