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Kumar P, Vahidzadeh E, Alam KM, Laishram D, Cui K, Shankar K. Radial Nano-Heterojunctions Consisting of CdS Nanorods Wrapped by 2D CN:PDI Polymer with Deep HOMO for Photo-Oxidative Water Splitting, Dye Degradation and Alcohol Oxidation. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091481. [PMID: 37177028 PMCID: PMC10180281 DOI: 10.3390/nano13091481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 05/15/2023]
Abstract
Solar energy harvesting using semiconductor photocatalysis offers an enticing solution to two of the biggest societal challenges, energy scarcity and environmental pollution. After decades of effort, no photocatalyst exists which can simultaneously meet the demand for excellent absorption, high quantum efficiency and photochemical resilience/durability. While CdS is an excellent photocatalyst for hydrogen evolution, pollutant degradation and organic synthesis, photocorrosion of CdS leads to the deactivation of the catalyst. Surface passivation of CdS with 2D graphitic carbon nitrides (CN) such as g-C3N4 and C3N5 has been shown to mitigate the photocorrosion problem but the poor oxidizing power of photogenerated holes in CN limits the utility of this approach for photooxidation reactions. We report the synthesis of exfoliated 2D nanosheets of a modified carbon nitride constituted of tris-s-triazine (C6N7) linked pyromellitic dianhydride polydiimide (CN:PDI) with a deep oxidative highest occupied molecular orbital (HOMO) position, which ensures sufficient oxidizing power for photogenerated holes in CN. The heterojunction formed by the wrapping of mono-/few layered CN:PDI on CdS nanorods (CdS/CN:PDI) was determined to be an excellent photocatalyst for oxidation reactions including photoelectrochemical water splitting, dye decolorization and the photocatalytic conversion of benzyl alcohol to benzaldehyde. Extensive structural characterization using HR-TEM, Raman, XPS, etc., confirmed wrapping of few-layered CN:PDI on CdS nanorods. The increased photoactivity in CdS/CN:PDI catalyst was ascribed to facile electron transfer from CdS to CN:PDI in comparison to CdS/g-C3N4, leading to an increased electron density on the surface of the photocatalyst to drive chemical reactions.
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Affiliation(s)
- Pawan Kumar
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St., Edmonton, AB T6G 1H9, Canada
- Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive NW, Calgary, AB T2N 1N4, Canada
| | - Ehsan Vahidzadeh
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St., Edmonton, AB T6G 1H9, Canada
| | - Kazi M Alam
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St., Edmonton, AB T6G 1H9, Canada
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, AB T6G 2M9, Canada
| | - Devika Laishram
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St., Edmonton, AB T6G 1H9, Canada
- Department of Chemistry, Indian Institute of Technology Jodhpur, Jodhpur 34201, India
| | - Kai Cui
- Nanotechnology Research Centre, National Research Council of Canada, Edmonton, AB T6G 2M9, Canada
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St., Edmonton, AB T6G 1H9, Canada
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Patel SK, Udayakumar AK, Mahendran G, Vasudevan B, Surve J, Parmar J. Highly efficient, perfect, large angular and ultrawideband solar energy absorber for UV to MIR range. Sci Rep 2022; 12:18044. [PMID: 36302877 DOI: 10.1038/s41598-022-22951-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 10/21/2022] [Indexed: 11/09/2022] Open
Abstract
Although different materials and designs have been tried in search of the ideal as well as ultra-wideband light absorber, achieving ultra-broadband and robust unpolarized light absorption over a wide angular range has proven to be a major issue. Light-field regulation capabilities provided by optical metamaterials are a potential new technique for perfect absorbers. It is our goal to design and demonstrate an ultra-wideband solar absorber for the ultraviolet to a mid-infrared region that has an absorptivity of TE/TM light of 96.2% on average. In the visible, NIR, and MIR bands of the solar spectrum, the absorbed energy is determined to be over 97.9%, above 96.1%, and over 95%, respectively under solar radiation according to the Air Mass Index 1.5 (AM1.5) spectrum investigation. In order to achieve this wideband absorption, the TiN material ground layer is followed by the SiO2 layer, and on top of that, a Cr layer with patterned Ti-based resonators of circular and rectangular multiple patterns. More applications in integrated optoelectronic devices could benefit from the ideal solar absorber's strong absorption, large angular responses, and scalable construction.
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Affiliation(s)
- Shobhit K Patel
- Department of Computer Engineering, Marwadi University, Rajkot, Gujarat, 360003, India.
| | - Arun Kumar Udayakumar
- Department of EEE, SRM Institute of Science and Technology, Ramapuram Campus, Chennai, Tamilnadu, 600089, India
| | - G Mahendran
- Department of EEE, Kathir College of Engineering, Coimbatore, Tamilnadu, 641062, India
| | - B Vasudevan
- Department of Electronics and Communication Engineering, St. Joseph's College of Engineering, OMR, Chennai, 600119, India
| | - Jaymit Surve
- Department of Electrical Engineering, Marwadi University, Rajkot, Gujarat, 360003, India
| | - Juveriya Parmar
- Department of Electronics and Communication Engineering, Marwadi University, Rajkot, Gujarat, 360003, India.,Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, 1400 R St., Nebraska, 68588, USA
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Metamaterial Solar Absorber Based on Refractory Metal Titanium and Its Compound. COATINGS 2022. [DOI: 10.3390/coatings12070929] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Metamaterials refers to a class of artificial materials with special properties. Through its unique geometry and the small size of each unit, the material can acquire unique electromagnetic field properties that conventional materials do not have. Based on these factors, we put forward a kind of high absorption near-ultraviolet to near-infrared electromagnetic wave absorber of the solar energy. The surface structure of the designed absorber is composed of TiN-TiO2-Al2O3 with rectangles and disks, and the substrate is Ti-Al2O3-Ti layer. In the study band range (0.1–3.0 μm), the solar absorber’s average absorption is up to 96.32%, and the designed absorber absorbs more than 90% of the electromagnetic wave with a wavelength width of 2.577 μm (0.413–2.990 μm). Meanwhile, the designed solar absorber has good performance under different angles of oblique incident light. Ultra-wideband solar absorbers have great potential in light absorption related applicaitions because of their wide spectrum high absorption properites.
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Patel SK, Surve J, Katkar V, Parmar J. Optimization of Metamaterial‐Based Solar Energy Absorber for Enhancing Solar Thermal Energy Conversion Using Artificial Intelligence. ADVANCED THEORY AND SIMULATIONS 2022. [DOI: 10.1002/adts.202200139] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Shobhit K. Patel
- Department of Computer Engineering Marwadi University Rajkot Gujarat 36003 India
| | - Jaymit Surve
- Department of Electrical Engineering Marwadi University Rajkot Gujarat 360003 India
| | - Vijay Katkar
- Department of Computer Engineering Marwadi University Rajkot Gujarat 36003 India
| | - Juveriya Parmar
- Department of Computer Engineering Marwadi University Rajkot Gujarat 36003 India
- Department of Mechanical and Materials Engineering University of Nebraska‐Lincoln 1400 R St. NE 68588 USA
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Chen J, Shi Y, Pan K, Du J, Qiu J. Plasma Oscillation Behavior and Electromagnetic Interference Shielding of Carbon Nanofibers/ Conductive Polymer Metacomposites at Radarwave Frequency. Macromol Rapid Commun 2022; 43:e2100826. [PMID: 35257427 DOI: 10.1002/marc.202100826] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/01/2022] [Indexed: 11/08/2022]
Abstract
Metacomposites have attracted widespread attention due to their unique negative electromagnetic properties and stupendous applications. Although there are systems that realize metamaterial properties in low radio frequency bands, the research on the construction of polymer matrix metacomposites with negative performance in the pivotal GHz band is still uncovered. Herein, the carbon nanofiber/conductive polymer metacomposites with three-dimensional overlapping network structures are innovatively constructed to achieve negative permittivity characteristics in the radarwave frequency range, and convenient methods for further adjusting the electromagnetic parameters is also proposed. The results show that the negative permittivity of CNFs/PANI metacomposites can be conveniently altered via adjusting PANI content. Furthermore, electromagnetic shielding has also been fully discussed as one of the most valuable applications of the metacomposites. The SET of CNFs/PANI-70 has an average value of 70 dB at 4-18 GHz and can reach a maximum of 80 dB at 4 GHz, which far exceeds the current commercial electromagnetic shielding standards. This work greatly broadens the promising application of metacomposites for perfect electromagnetic shielding, novel capacitance, and frequency selective surfaces. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Jiali Chen
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, PR China
| | - Yunan Shi
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, PR China
| | - Kaichao Pan
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, PR China
| | - Jiang Du
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, PR China.,Key Laboratory of Advanced Civil Engineering Materials (Tongji University), Education of Ministry, Shanghai, 201804, PR China
| | - Jun Qiu
- School of Materials Science and Engineering, Tongji University, Shanghai, 201804, PR China.,Key Laboratory of Advanced Civil Engineering Materials (Tongji University), Education of Ministry, Shanghai, 201804, PR China
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Xu X, Aggarwal D, Shankar K. Instantaneous Property Prediction and Inverse Design of Plasmonic Nanostructures Using Machine Learning: Current Applications and Future Directions. NANOMATERIALS 2022; 12:nano12040633. [PMID: 35214962 PMCID: PMC8874423 DOI: 10.3390/nano12040633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 02/06/2022] [Accepted: 02/08/2022] [Indexed: 02/06/2023]
Abstract
Advances in plasmonic materials and devices have given rise to a variety of applications in photocatalysis, microscopy, nanophotonics, and metastructures. With the advent of computing power and artificial neural networks, the characterization and design process of plasmonic nanostructures can be significantly accelerated using machine learning as opposed to conventional FDTD simulations. The machine learning (ML) based methods can not only perform with high accuracy and return optical spectra and optimal design parameters, but also maintain a stable high computing efficiency without being affected by the structural complexity. This work reviews the prominent ML methods involved in forward simulation and inverse design of plasmonic nanomaterials, such as Convolutional Neural Networks, Generative Adversarial Networks, Genetic Algorithms and Encoder–Decoder Networks. Moreover, we acknowledge the current limitations of ML methods in the context of plasmonics and provide perspectives on future research directions.
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TiO2-HfN Radial Nano-Heterojunction: A Hot Carrier Photoanode for Sunlight-Driven Water-Splitting. Catalysts 2021. [DOI: 10.3390/catal11111374] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The lack of active, stable, earth-abundant, and visible-light absorbing materials to replace plasmonic noble metals is a critical obstacle for researchers in developing highly efficient and cost-effective photocatalytic systems. Herein, a core–shell nanotube catalyst was fabricated consisting of atomic layer deposited HfN shell and anodic TiO2 support layer with full-visible regime photoactivity for photoelectrochemical water splitting. The HfN active layer has two unique characteristics: (1) A large bandgap between optical and acoustic phonon modes and (2) No electronic bandgap, which allows a large population of long life-time hot carriers, which are used to enhance the photoelectrochemical performance. The photocurrent density (≈2.5 mA·cm−2 at 1 V vs. Ag/AgCl) obtained in this study under AM 1.5G 1 Sun illumination is unprecedented, as it is superior to most existing plasmonic noble metal-decorated catalysts and surprisingly indicates a photocurrent response that extends to 730 nm. The result demonstrates the far-reaching application potential of replacing active HER/HOR noble metals such as Au, Ag, Pt, Pd, etc. with low-cost plasmonic ceramics.
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Vahidzadeh E, Zeng S, Alam KM, Kumar P, Riddell S, Chaulagain N, Gusarov S, Kobryn AE, Shankar K. Harvesting Hot Holes in Plasmon-Coupled Ultrathin Photoanodes for High-Performance Photoelectrochemical Water Splitting. ACS APPLIED MATERIALS & INTERFACES 2021; 13:42741-42752. [PMID: 34476945 DOI: 10.1021/acsami.1c10698] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The harvesting of hot carriers produced by plasmon decay to generate electricity or drive a chemical reaction enables the reduction of the thermalization losses associated with supra-band gap photons in semiconductor photoelectrochemical (PEC) cells. Through the broadband harvesting of light, hot-carrier PEC devices also produce a sensitizing effect in heterojunctions with wide-band gap metal oxide semiconductors possessing good photostability and catalytic activity but poor absorption of visible wavelength photons. There are several reports of hot electrons in Au injected over the Schottky barrier into crystalline TiO2 and subsequently utilized to drive a chemical reaction but very few reports of hot hole harvesting. In this work, we demonstrate the efficient harvesting of hot holes in Au nanoparticles (Au NPs) covered with a thin layer of amorphous TiO2 (a-TiO2). Under AM1.5G 1 sun illumination, photoanodes consisting of a single layer of ∼50 nm diameter Au NPs coated with a 10 nm shell of a-TiO2 (Au@a-TiO2) generated 2.5 mA cm-2 of photocurrent in 1 M KOH under 0.6 V external bias, rising to 3.7 mA cm-2 in the presence of a hole scavenger (methanol). The quantum yield for hot-carrier-mediated photocurrent generation was estimated to be close to unity for high-energy photons (λ < 420 nm). Au@a-TiO2 photoelectrodes produced a small positive photocurrent of 0.1 mA cm-2 even at a bias of -0.6 V indicating extraction of hot holes even at a strong negative bias. These results together with density functional theory modeling and scanning Kelvin probe force microscope data indicate fast injection of hot holes from Au NPs into a-TiO2 and light harvesting performed near-exclusively by Au NPs. For comparison, Au NPs coated with a 10 nm shell of Al2O3 (Au@Al2O3) generated 0.02 mA cm-2 of photocurrent in 1 M KOH under 0.6 V external bias. These results underscore the critical role played by a-TiO2 in the extraction of holes in Au@a-TiO2 photoanodes, which is not replicated by an ordinary dielectric shell. It is also demonstrated here that an ultrathin photoanode (<100 nm in maximum thickness) can efficiently drive sunlight-driven water splitting.
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Affiliation(s)
- Ehsan Vahidzadeh
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Sheng Zeng
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Kazi M Alam
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Pawan Kumar
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Saralyn Riddell
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Narendra Chaulagain
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
| | - Sergey Gusarov
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Alexander E Kobryn
- Nanotechnology Research Centre, National Research Council Canada, 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 Street, Edmonton, Alberta T6G 1H9, Canada
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Zhou F, Qin F, Yi Z, Yao W, Liu Z, Wu X, Wu P. Ultra-wideband and wide-angle perfect solar energy absorber based on Ti nanorings surface plasmon resonance. Phys Chem Chem Phys 2021; 23:17041-17048. [PMID: 34342321 DOI: 10.1039/d1cp03036a] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Solar energy absorption is a very important field in photonics. The successful development of an efficient, wide-band solar absorber is an extremely powerful driver in this field. We propose an ultra-wideband (UWB) solar energy absorber composed of a Ti ring and SiO2-Si3N4-Ti thin films. In the range of 300-4000 nm, the wide band has an absorption efficiency of more than 90% and can reach 3683 nm, and it has four absorption peaks with a high absorptivity. Moreover, the weighted average absorption efficiency of the solar absorber under AM 1.5 is maintained above 97.03%, which indicates it has great potential for use in the field of solar energy absorption. Moreover, we proved that the polarization is insensitive by analyzing the absorption characteristics at arbitrary polarization angles. For both the transverse electric (TE) and transverse magnetic (TM) modes, the UWB absorption is maintained at more than 90% in the wide incidence angle range of 60°. The UWB solar energy absorber has great potential for use in a variety of applications, such as converting solar light and heat into electricity for public use and reducing the side effects of coal-fired power generation. It can also be used in information detection and infrared thermal imaging owing to its UWB characteristics.
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Affiliation(s)
- Fengqi Zhou
- School of Science, East China Jiaotong University, Nanchang 330013, China.
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Wu P, Wei K, Xu D, Chen M, Zeng Y, Jian R. Ultra-Wideband and Wide-Angle Perfect Solar Energy Absorber Based on Titanium and Silicon Dioxide Colloidal Nanoarray Structure. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:2040. [PMID: 34443871 PMCID: PMC8398894 DOI: 10.3390/nano11082040] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/30/2021] [Accepted: 08/07/2021] [Indexed: 11/16/2022]
Abstract
In this paper, we designed an ultra-wideband solar energy absorber and approved it numerically by the finite-difference time-domain simulation. The designed solar energy absorber can achieve a high absorption of more than 90% of light in a continuous 3.506 μm (0.596 μm-4.102 μm) wavelength range. The basic structure of the absorber is based on silicon dioxide colloidal crystal and Ti. Since the materials have a high melting point, the designed solar energy absorber can work normally under high temperature, and the structure of this solar energy absorber is simpler than most solar energy absorbers fabricated with traditional metal. In the entire wavelength band researched, the average absorption of the colloidal crystal-based solar energy absorber is as high as 94.3%, demonstrating an excellent performance under the incidence light of AM 1.5 solar spectrum. In the meantime, the absorption spectrum of the solar energy absorber is insensitive to the polarization of light. In comparison to other similar structures, our designed solar energy absorber has various advantages, such as its high absorption in a wide spectrum range and that it is low cost and easy to make.
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Affiliation(s)
- Pinghui Wu
- Fujian Provincial Key Laboratory for Advanced Micro-Nano Photonics Technology and Devices, Quanzhou Normal University, Quanzhou 362000, China; (P.W.); (M.C.); (Y.Z.)
| | - Kaihua Wei
- School of Automation, Hangzhou Dianzi University, Hangzhou 310018, China;
| | - Danyang Xu
- College of Science, Zhejiang University of Technology, Hangzhou 310023, China;
| | - Musheng Chen
- Fujian Provincial Key Laboratory for Advanced Micro-Nano Photonics Technology and Devices, Quanzhou Normal University, Quanzhou 362000, China; (P.W.); (M.C.); (Y.Z.)
| | - Yongxi Zeng
- Fujian Provincial Key Laboratory for Advanced Micro-Nano Photonics Technology and Devices, Quanzhou Normal University, Quanzhou 362000, China; (P.W.); (M.C.); (Y.Z.)
| | - Ronghua Jian
- School of Science, Huzhou University, Huzhou 313000, China
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Manuel AP, Shankar K. Hot Electrons in TiO 2-Noble Metal Nano-Heterojunctions: Fundamental Science and Applications in Photocatalysis. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1249. [PMID: 34068571 PMCID: PMC8151081 DOI: 10.3390/nano11051249] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/03/2021] [Accepted: 05/05/2021] [Indexed: 01/06/2023]
Abstract
Plasmonic photocatalysis enables innovation by harnessing photonic energy across a broad swathe of the solar spectrum to drive chemical reactions. This review provides a comprehensive summary of the latest developments and issues for advanced research in plasmonic hot electron driven photocatalytic technologies focusing on TiO2-noble metal nanoparticle heterojunctions. In-depth discussions on fundamental hot electron phenomena in plasmonic photocatalysis is the focal point of this review. We summarize hot electron dynamics, elaborate on techniques to probe and measure said phenomena, and provide perspective on potential applications-photocatalytic degradation of organic pollutants, CO2 photoreduction, and photoelectrochemical water splitting-that benefit from this technology. A contentious and hitherto unexplained phenomenon is the wavelength dependence of plasmonic photocatalysis. Many published reports on noble metal-metal oxide nanostructures show action spectra where quantum yields closely follow the absorption corresponding to higher energy interband transitions, while an equal number also show quantum efficiencies that follow the optical response corresponding to the localized surface plasmon resonance (LSPR). We have provided a working hypothesis for the first time to reconcile these contradictory results and explain why photocatalytic action in certain plasmonic systems is mediated by interband transitions and in others by hot electrons produced by the decay of particle plasmons.
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Affiliation(s)
- Ajay P. Manuel
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada;
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB T6G 1H9, Canada;
- Future Energy Systems Research Institute, University of Alberta, Edmonton, AB T6G 1K4, Canada
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12
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Trends in the Implementation of Advanced Plasmonic Materials in Optical Fiber Sensors (2010–2020). CHEMOSENSORS 2021. [DOI: 10.3390/chemosensors9040064] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In recent years, the interaction between light and metallic films have been proven to be a highly powerful tool for optical sensing applications. We have witnessed the development of highly sensitive commercial devices based on Surface Plasmon Resonances. There has been continuous effort to integrate this plasmonic sensing technology using micro and nanofabrication techniques with the optical fiber sensor world, trying to get better, smaller and cost-effective high performance sensing solutions. In this work, we present a review of the latest and more relevant scientific contributions to the optical fiber sensors field using plasmonic materials over the last decade. The combination of optical fiber technology with metallic micro and nanostructures that allow plasmonic interactions have opened a complete new and promising field of study. We review the main advances in the integration of such metallic micro/nanostructures onto the optical fibers, discuss the most promising fabrication techniques and show the new trends in physical, chemical and biological sensing applications.
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Vahidzadeh E, Shankar K. Artificial Neural Network-Based Prediction of the Optical Properties of Spherical Core-Shell Plasmonic Metastructures. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:633. [PMID: 33806266 PMCID: PMC8001937 DOI: 10.3390/nano11030633] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 02/24/2021] [Accepted: 02/26/2021] [Indexed: 12/24/2022]
Abstract
The substitution of time- and labor-intensive empirical research as well as slow finite difference time domain (FDTD) simulations with revolutionary techniques such as artificial neural network (ANN)-based predictive modeling is the next trend in the field of nanophotonics. In this work, we demonstrated that neural networks with proper architectures can rapidly predict the far-field optical response of core-shell plasmonic metastructures. The results obtained with artificial neural networks are comparable with FDTD simulations in accuracy but the speed of obtaining them is between 100-1000 times faster than FDTD simulations. Further, we have proven that ANNs does not have problems associated with FDTD simulations such as dependency of the speed of convergence on the size of the structure. The other trend in photonics is the inverse design problem, where the far-field optical response of a spherical core-shell metastructure can be linked to the design parameters such as type of the material(s), core radius, and shell thickness using a neural network. The findings of this paper provide evidence that machine learning (ML) techniques such as artificial neural networks can potentially replace time-consuming finite domain methods in the future.
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Affiliation(s)
| | - Karthik Shankar
- Department of Electrical and Computer Engineering, University of Alberta, 9211-116 St, Edmonton, AB T6G 1H9, Canada;
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14
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Fu T, Chen Y, Du C, Yang W, Zhang R, Sun L, Shi D. Numerical investigation of plasmon sensitivity and surface-enhanced Raman scattering enhancement of individual TiN nanosphere multimers. NANOTECHNOLOGY 2020; 31:135210. [PMID: 31835258 DOI: 10.1088/1361-6528/ab61d3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Titanium nitride (TiN) nanoparticles have recently been considered as potential candidate plasmonic materials; such materials support localized surface plasmon resonances (LSPRs) and show excellent thermal stability with a high melting point. The electromagnetic (EM) field coupling and gap distance between components of individual TiN nanosphere multimers are critical parameters affecting their plasmonic sensitivity and surface-enhanced Raman scattering (SERS) performance, both of which are numerically investigated by the finite element method. It is demonstrated that the fractional shifts of both the dipolar LSPR wavelength [Formula: see text] and the refractive index sensitivity factor S follow the universal 'plasmon ruler' behavior, which is explained well in terms of EM field distribution. The response of the obtained S to [Formula: see text] is also presented and elucidated in terms of the optical response of the dielectric constants of TiN. The maximum S and SERS enhancement (excited by three normally available lasers in experiments) are also predicted; both are comparable to the values for Au dimeric nanoparticles. The present work holds great promise for the development of non-noble metal plasmonic materials in both SERS and plasmonic sensing applications.
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Affiliation(s)
- TianYi Fu
- College of Science, Nanjing University of Aeronautics and Astronautics, Nanjing 211100, People's Republic of China
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15
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Cao P, Chen H, Liang M, Dou J, Cheng L. New coupling mechanism of titanium nitride nanosphere dimers at short separation distances. NANOTECHNOLOGY 2019; 30:335204. [PMID: 31035275 DOI: 10.1088/1361-6528/ab1dcd] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The coupled localized plasmon modes generated by a metal plasmonic nanoparticle (NP) dimer induces a stronger plasmon enhanced electromagnetic field as well as a stronger optical response compared to that of a single NP. Owing to the small Drude damping factor, however, the absorption bandwidth of noble metallic NPs is insufficiently broad. Herein, the near-field wide band coupling absorption for 25 nm diameter TiN nanospheres is investigated in a homo-dimer arrangement for various separation distances using the finite element method. An enhancement of the wide band coupling absorption and a red-shift is found, which can be explained by an uncomplicated dipole-dipole coupling model at interparticle distances greater than 5 nm. At short separation distances, the coupling absorption of the TiN dimer exhibits a tremendous change, which is diametrically opposite the results found for a Au dimer. This unexpected change phenomenon is shown by calculation and analysis to be owing to the change of the charge distribution approach at short separation distances, which is demonstrated to play a key role in the wide band coupling characteristic variation. With decreasing separation gap, a new coupling mechanism caused by surface charge properties is responsible for the decline in coupling absorption as well as the break in the ruler equations for both plasmon shift and temperature enhancement.
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Affiliation(s)
- Pengfei Cao
- School of Information Science and Engineering, Lanzhou University, Lanzhou, 730000, People's Republic of China
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