Nanomaterials

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19 pages, 6908 KiB

Open AccessArticle

Impact of Pretreatment of the Bulk Starting Material on the Efficiency of Liquid Phase Exfoliation of WS₂

by Steffen Ott, Melanie Lakmann and Claudia Backes

Nanomaterials 2021, 11(5), 1072; https://doi.org/10.3390/nano11051072 - 22 Apr 2021

Cited by 8 | Viewed by 3120

Abstract

Liquid phase exfoliation (LPE) is widely used to produce colloidal dispersions of nanomaterials, in particular two-dimensional nanosheets. The degree of exfoliation, i.e., the length to thickness aspect ratio was shown to be intrinsically limited by the ratio of in-plane to out-of-plane binding strength. [...] Read more.

Liquid phase exfoliation (LPE) is widely used to produce colloidal dispersions of nanomaterials, in particular two-dimensional nanosheets. The degree of exfoliation, i.e., the length to thickness aspect ratio was shown to be intrinsically limited by the ratio of in-plane to out-of-plane binding strength. In this work, we investigate whether simple pretreatment of the starting material can be used to change the in-plane to out-of-plane binding strength through mild intercalation to improve the sample quality in sonication-assisted LPE. Five different pretreatment conditions of WS₂ were tested and the dispersions size-selected through centrifugation. From optical spectroscopy (extinction, Raman, photoluminescence), information on nanosheet dimension (average lateral size, layer number, monolayer size) and optical quality (relative photoluminescence quantum yield) was extracted. We find that the pretreatment has a minor impact on the length/thickness aspect ratio, but that photoluminescence quantum yield can be increased in particular using mild sonication conditions. We attribute this to the successful exfoliation of nanosheets with a lower degree of basal plane defectiveness. This work emphasizes the complexity of the exfoliation process and suggests that the role of defects has to be considered for a comprehensive picture. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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11 pages, 2724 KiB

Open AccessArticle

Filling Exciton Trap-States in Two-Dimensional Tungsten Disulfide (WS₂) and Diselenide (WSe₂) Monolayers

by Zeynep Ezgi Eroglu, Dillon Contreras, Pouya Bahrami, Nurul Azam, Masoud Mahjouri-Samani and Abdelaziz Boulesbaa

Nanomaterials 2021, 11(3), 770; https://doi.org/10.3390/nano11030770 - 18 Mar 2021

Cited by 12 | Viewed by 3964

Abstract

Two-dimensional transition metal dichalcogenides (2D-TMDs) hold a great potential to platform future flexible optoelectronics. The beating hearts of these materials are their excitons known as X_A and X_B, which arise from transitions between spin-orbit split (SOS) levels in the conduction [...] Read more.

Two-dimensional transition metal dichalcogenides (2D-TMDs) hold a great potential to platform future flexible optoelectronics. The beating hearts of these materials are their excitons known as X_A and X_B, which arise from transitions between spin-orbit split (SOS) levels in the conduction and valence bands at the K-point. The functionality of 2D-TMD-based devices is determined by the dynamics of these excitons. One of the most consequential channels of exciton decay on the device functionality is the defect-assisted recombination (DAR). Here, we employ steady-state absorption and emission spectroscopies, and pump density-dependent femtosecond transient absorption spectroscopy to report on the effect of DAR on the lifetime of excitons in monolayers of tungsten disulfide (2D-WS₂) and diselenide (2D-WSe₂). These pump-probe measurements suggested that while exciton decay dynamics in both monolayers are driven by DAR, in 2D-WS₂, defect states near the X_B exciton fill up before those near the X_A exciton. However, in the 2D-WSe₂ monolayer, the defect states fill up similarly. Understanding the contribution of DAR on the lifetime of excitons and the partition of this decay channel between X_A and X_B excitons may open new horizons for the incorporation of 2D-TMD materials in future optoelectronics. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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16 pages, 5535 KiB

Open AccessArticle

Surface Enhanced Raman Spectroscopy With Electrodeposited Copper Ultramicro-Wires With/Without Silver Nanostars Decoration

by Margherita Longoni, Maria Sole Zalaffi, Lavinia de Ferri, Angela Maria Stortini, Giulio Pojana and Paolo Ugo

Nanomaterials 2021, 11(2), 518; https://doi.org/10.3390/nano11020518 - 18 Feb 2021

Cited by 9 | Viewed by 3777

Abstract

The electrochemical preparation of arrays of copper ultramicrowires (CuUWs) by using porous membranes as templates is critically revisited, with the goal of obtaining cheap but efficient substrates for surface enhanced Raman spectroscopy (SERS). The role of the materials used for the electrodeposition is [...] Read more.

The electrochemical preparation of arrays of copper ultramicrowires (CuUWs) by using porous membranes as templates is critically revisited, with the goal of obtaining cheap but efficient substrates for surface enhanced Raman spectroscopy (SERS). The role of the materials used for the electrodeposition is examined, comparing membranes of anodized aluminum oxide (AAO) vs. track-etched polycarbonate (PC) as well as copper vs. glassy carbon (GC) as electrode material. A voltammetric study performed on bare electrodes and potentiostatic tests on membrane coated electrodes allowed the optimization of the deposition parameters. The final arrays of CuUWs were obtained by chemical etching of the template, with NaOH for AAO and CH₂Cl₂ for PC. After total etching of the template, SERS spectra were recorded on CuUWs using benzenethiol as SERS probe with known spectral features. The CuUW substrates displayed good SERS properties, providing enhancement factor in the 10³–10⁴ range. Finally, it was demonstrated that higher Raman enhancement can be achieved when CuUWs are decorated with silver nanostars, supporting the formation of SERS active hot-spots at the bimetallic interface. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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13 pages, 19209 KiB

Open AccessArticle

Tunable Broadband Terahertz Waveband Absorbers Based on Fractal Technology of Graphene Metamaterial

by Tong Xie, Dingbo Chen, Huiping Yang, Yanhong Xu, Zhenrong Zhang and Junbo Yang

Nanomaterials 2021, 11(2), 269; https://doi.org/10.3390/nano11020269 - 20 Jan 2021

Cited by 27 | Viewed by 3077

Abstract

In this paper, a metasurface Terahertz absorber based on the fractal technology of a graphene geometry resonator to realize ultra-wideband, ultrathin, adjustable double-layer cross-fractal formation is introduced. This paper proposes a dynamically tuned graphene absorbing material. The structure is composed of one- to [...] Read more.

In this paper, a metasurface Terahertz absorber based on the fractal technology of a graphene geometry resonator to realize ultra-wideband, ultrathin, adjustable double-layer cross-fractal formation is introduced. This paper proposes a dynamically tuned graphene absorbing material. The structure is composed of one- to four-level-fractal graphene pattern layers, MgF₂ layers and metal reflective layers to form a two-sided mirror of an asymmetric Fabry–Perot cavity. To confine the terahertz electromagnetic wave, four different fractals are integrated into a supercell, and the coupling and superposition of adjacent resonant cavities form a broadband high-absorption absorber. Using finite element-based full-wave electromagnetic simulation software to simulate the response frequency of 0.4–2.0 THz, we found that the absorber achieves a broadband 1.26 THz range (absorption > 80%) and a relative bandwidth of 106.8%. By adjusting the Fermi energy, it can realize free switching and expand to wider broadband terahertz absorption, by adjusting the polarization angle (Φ) from 0 to 90° to prove that the structure is not sensitive to polarization, the absorber provides a 60° large angle of incidence, polarization for TE and TM the absorption pattern remains basically the same. Compared with the previous work, our proposed structure uses fractal technology to expand the bandwidth and provide dynamic adjustable characteristics with great degrees of freedom. The appearance of the fractal structure reduces the difficulty of actual processing. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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11 pages, 3055 KiB

Open AccessArticle

Theoretical Analysis of Terahertz Dielectric–Loaded Graphene Waveguide

by Da Teng and Kai Wang

Nanomaterials 2021, 11(1), 210; https://doi.org/10.3390/nano11010210 - 15 Jan 2021

Cited by 29 | Viewed by 2705

Abstract

The waveguiding of terahertz surface plasmons by a GaAs strip-loaded graphene waveguide is investigated based on the effective-index method and the finite element method. Modal properties of the effective mode index, modal loss, and cut-off characteristics of higher order modes are investigated. By [...] Read more.

The waveguiding of terahertz surface plasmons by a GaAs strip-loaded graphene waveguide is investigated based on the effective-index method and the finite element method. Modal properties of the effective mode index, modal loss, and cut-off characteristics of higher order modes are investigated. By modulating the Fermi level, the modal properties of the fundamental mode could be adjusted. The accuracy of the effective-index method is verified by a comparison between the analytical results and numerical simulations. Besides the modal properties, the crosstalk between the adjacent waveguides, which determines the device integration density, is studied. The findings show that the effective-index method is highly valid for analyzing dielectric-loaded graphene plasmon waveguides in the terahertz region and may have potential applications in subwavelength tunable integrated photonic devices. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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9 pages, 1358 KiB

Open AccessArticle

Hysteresis Analysis of Hole-Transport-Material-Free Monolithic Perovskite Solar Cells with Carbon Counter Electrode by Current Density–Voltage and Impedance Spectra Measurements

by Syed Afaq Ali Shah, Muhammad Hassan Sayyad, Jinghua Sun and Zhongyi Guo

Nanomaterials 2021, 11(1), 48; https://doi.org/10.3390/nano11010048 - 27 Dec 2020

Cited by 20 | Viewed by 4130

Abstract

Due to the tremendous increase in power conversion efficiency (PCE) of organic–inorganic perovskite solar cells (PSCs), this technology has attracted much attention. Despite being the fastest-growing photovoltaic technology to date, bottlenecks such as current density–voltage (J–V) hysteresis have significantly limited further [...] Read more.

Due to the tremendous increase in power conversion efficiency (PCE) of organic–inorganic perovskite solar cells (PSCs), this technology has attracted much attention. Despite being the fastest-growing photovoltaic technology to date, bottlenecks such as current density–voltage (J–V) hysteresis have significantly limited further development. Current density measurements performed with different sweep scan speeds exhibit hysteresis and the photovoltaic parameters extracted from the current density–voltage measurements for both scan directions become questionable. A current density–voltage measurement protocol needs to be established which can be used to achieve reproducible results and to compare devices made in different laboratories. In this work, we report a hysteresis analysis of a hole-transport-material-free (HTM-free) carbon-counter-electrode-based PSC conducted by current density–voltage and impedance spectra measurements. The effect of sweep scan direction and time delay was examined on the J–V characteristics of the device. The hysteresis was observed to be strongly sweep scan direction and time delay dependent and decreased as the delay increased. The J–V analysis conducted in the reverse sweep scan direction at a lower sweep time delay of 0.2 s revealed very large increases in the short circuit current density and the power conversion efficiency of 57.7% and 56.1%, respectively, compared with the values obtained during the forward scan under the same conditions. Impedance spectroscopy (IS) investigations were carried out and the effects of sweep scan speed, time delay, and frequency were analyzed. The hysteresis was observed to be strongly sweep scan direction, sweep time delay, and frequency dependent. The correlation between J–V and IS data is provided. The wealth of photovoltaic and impendence spectroscopic data reported in this work on the hysteresis study of the HTM-free PSC may help in establishing a current density–voltage measurement protocol, identifying components and interfaces causing the hysteresis, and modeling of PSCs, eventually benefiting device performance and long-term stability. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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15 pages, 4872 KiB

Open AccessArticle

Self-Assembly Synthesis of the MoS₂/PtCo Alloy Counter Electrodes for High-Efficiency and Stable Low-Cost Dye-Sensitized Solar Cells

by Zhi Zeng, Dongbo Wang, Jinzhong Wang, Shujie Jiao, Yuewu Huang, Sixiang Zhao, Bingke Zhang, Mengyu Ma, Shiyong Gao, Xingguo Feng and Liancheng Zhao

Nanomaterials 2020, 10(9), 1725; https://doi.org/10.3390/nano10091725 - 31 Aug 2020

Cited by 7 | Viewed by 2973

Abstract

In this work, MoS₂ microspheres/PtCo-alloy nanoparticles (MoS₂/PtCo-alloy NPs) were composited via a novel and facile process which MoS₂ is functionalized by poly (N-vinyl-2-pyrrolidone) (PVP) and self-assembled with PtCo-alloy NPs. This new composite shows excellent electrocatalytic activity and great potential [...] Read more.

In this work, MoS₂ microspheres/PtCo-alloy nanoparticles (MoS₂/PtCo-alloy NPs) were composited via a novel and facile process which MoS₂ is functionalized by poly (N-vinyl-2-pyrrolidone) (PVP) and self-assembled with PtCo-alloy NPs. This new composite shows excellent electrocatalytic activity and great potential for dye-sensitized solar cells (DSSCs) as a counter electrode (CE) material. Benefiting from heterostructure and synergistic effects, the MoS₂/PtCo-alloy NPs exhibit high electrocatalytic activity, low charge-transfer resistance and stability in the cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) test. Meanwhile, a high power-conversion efficiency (PCE) of 8.46% is achieved in DSSCs with MoS₂/PtCo-alloy NP CEs, which are comparable to traditional Pt CEs (8.45%). This novel composite provides a new high-performance, stable and cheap choice for CEs in DSSCs. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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11 pages, 971 KiB

Open AccessArticle

Reducing Amplified Spontaneous Emission Threshold in CsPbBr₃ Quantum Dot Films by Controlling TiO₂ Compact Layer

by Saif M. H. Qaid, Fahhad H. Alharbi, Idriss Bedja, Mohammad Khaja Nazeeruddin and Abdullah S. Aldwayyan

Nanomaterials 2020, 10(8), 1605; https://doi.org/10.3390/nano10081605 - 15 Aug 2020

Cited by 18 | Viewed by 3553

Abstract

Amplified spontaneous emission (ASE) threshold in

{CsPbBr}_{3}

quantum dot films is systematically reduced by introducing high quality

{TiO}_{2}

compact layer grown by atomic-layer deposition. Uniform and pinhole-free

{TiO}_{2}

films of thickness 10, 20 and 50 nm are used as a [...] Read more.

Amplified spontaneous emission (ASE) threshold in

{CsPbBr}_{3}

quantum dot films is systematically reduced by introducing high quality

{TiO}_{2}

compact layer grown by atomic-layer deposition. Uniform and pinhole-free

{TiO}_{2}

films of thickness 10, 20 and 50 nm are used as a substrates for

{CsPbBr}_{3}

quantum dot films to enhance amplified spontaneous emission performance. The reduction is attributed indirectly to the improved morphology of

{TiO}_{2}

compact layer and subsequently

{CsPbBr}_{3}

active layer as grown on better quality substrates. This is quantified by the reduced roughness of the obtained films to less than 5 nm with 50 nm

{TiO}_{2}

substrate. Considering the used growth method for the quantum dot film, the improved substrate morphology maintains better the structure of the used quantum dots in the precursor solution. This results in better absorption and hence lower threshold of ASE. Besides that, the improved film quality results further in reducing light scattering and hence additional slight optical enhancement. The work demonstrates a potential venue to reduce the amplified spontaneous emission threshold of quantum dot films and therefore enhanced their optical performance. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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21 pages, 5588 KiB

Open AccessArticle

Preparation of Pt/γ-Bi₂MoO₆ Photocatalysts and Their Performance in α-Alkylation Reaction under Visible Light Irradiation

by Haiying Li, Xiujuan Yu, Xueli Hao, Zhiying Zhang, Yan Wang and Jingyi Li

Nanomaterials 2020, 10(4), 646; https://doi.org/10.3390/nano10040646 - 30 Mar 2020

Cited by 8 | Viewed by 2473

Abstract

Bi(NO₃)₃·5H₂O and (NH₄)₆Mo₇O₂₄·4H₂O were used as precursors to synthesize flaky γ-Bi₂MoO₆ samples by a hydrothermal method, and Pt/γ-Bi₂MoO₆ samples with different [...] Read more.

Bi(NO₃)₃·5H₂O and (NH₄)₆Mo₇O₂₄·4H₂O were used as precursors to synthesize flaky γ-Bi₂MoO₆ samples by a hydrothermal method, and Pt/γ-Bi₂MoO₆ samples with different mass fractions were prepared by an NaBH₄ reduction method. Alpha alkylation of benzyl alcohol and acetophenone with photocatalysts under visible light irradiation was performed, and the activity of 4 wt % Pt/γ-Bi₂MoO₆ (γ-Bi₂MoO₆ was prepared by a nitric acid method, pH = 9, and reaction temperature 180 °C) was the best. The photocatalytic reaction conditions were optimized by changing various kinds of variables, such as the type of catalyst, solvent, and base, and the amount of base, catalyst, and reactant. The optimal conditions for the organic reaction were 75 mg 4 wt % Pt/γ-Bi₂MoO₆, 6 mL n-heptane, 1.2 mmol NaOH, 1 mmol acetophenone, and 3 mmol benzyl alcohol. Under the optimal reaction conditions, the effects of different light wavelengths and light intensities on the reaction were measured, and the cycling ability of the photocatalyst was tested. After five cycles, the photochemical properties of the catalyst were relatively stable. Finally, the active substances were identified (such as electrons (e⁻), holes (h⁺), hydroxyl radicals (•OH), and superoxide radicals (•O₂⁻). Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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13 pages, 4608 KiB

Open AccessArticle

High-Power Large-Energy Raman Soliton Generations Within a Mode-Locked Yb-Doped Fiber Laser Based on High-Damage-Threshold CVD-MoS₂ as Modulator

by Pengfei Ma, Wei Lin, Huanian Zhang, Shanhui Xu and Zhongmin Yang

Nanomaterials 2019, 9(9), 1305; https://doi.org/10.3390/nano9091305 - 12 Sep 2019

Cited by 4 | Viewed by 2870

Abstract

In our work, based on a high-damage-threshold MoS₂ saturable absorber (SA), high-power intra-cavity Raman solitons within a passively mode-locked Yb-doped fiber laser were demonstrated successfully for the first time. The damage threshold of the MoS₂ SA was as high as ~0.48 [...] Read more.

In our work, based on a high-damage-threshold MoS₂ saturable absorber (SA), high-power intra-cavity Raman solitons within a passively mode-locked Yb-doped fiber laser were demonstrated successfully for the first time. The damage threshold of the MoS₂ SA was as high as ~0.48 J/cm². By adjusting the polarization states, stable single- or dual-pulse Raman soliton operations were obtained. The maximum average output power for single-pulse and dual-pulse Raman soliton operations was 80.11 and 89.33 mW, respectively. Our experiment results show significant enhancement in comparison with previous works, which provides fundamental guidance for future designs of high-power, large-energy, intra-cavity Raman soliton generations based on two-dimensional materials as SAs. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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19 pages, 2466 KiB

Open AccessArticle

The Effect of Acceptor Structure on Emission Color Tuning in Organic Semiconductors with D–π–A–π–D Structures

by Przemyslaw Ledwon, Gabriela Wiosna-Salyga, Marian Chapran and Radoslaw Motyka

Nanomaterials 2019, 9(8), 1179; https://doi.org/10.3390/nano9081179 - 17 Aug 2019

Cited by 8 | Viewed by 4418

Abstract

A series of novel donor–acceptor D–π–A–π–D compounds were synthesized and characterized in order to determine the influence of different acceptor units on their properties. The introduction of acceptor moieties had a direct impact on the HOMO and LUMO energy levels. Fluorescence spectra of [...] Read more.

A series of novel donor–acceptor D–π–A–π–D compounds were synthesized and characterized in order to determine the influence of different acceptor units on their properties. The introduction of acceptor moieties had a direct impact on the HOMO and LUMO energy levels. Fluorescence spectra of compounds can be changed by the choice of an appropriate acceptor and were shifted from the green to the near-infrared part of spectra. Due to observed concentration induced emission quenching, the green exciplex type host was used to evaluate the potential of synthesized molecules as emitters in organic light emitting diodes (OLEDs). Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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15 pages, 2979 KiB

Open AccessArticle

Plasmonic Colour Printing by Light Trapping in Two-Metal Nanostructures

by Keith Wilson, Cristian A. Marocico, Esteban Pedrueza-Villalmanzo, Christopher Smith, Calin Hrelescu and A. Louise Bradley

Nanomaterials 2019, 9(7), 963; https://doi.org/10.3390/nano9070963 - 1 Jul 2019

Cited by 3 | Viewed by 3789

Abstract

Structural colour generation by nanoscale plasmonic structures is of major interest for non-bleaching colour printing, anti-counterfeit measures and decoration applications. We explore the physics of a two-metal plasmonic nanostructure consisting of metallic nanodiscs separated from a metallic back-reflector by a uniform thin polymer [...] Read more.

Structural colour generation by nanoscale plasmonic structures is of major interest for non-bleaching colour printing, anti-counterfeit measures and decoration applications. We explore the physics of a two-metal plasmonic nanostructure consisting of metallic nanodiscs separated from a metallic back-reflector by a uniform thin polymer film and investigate the potential for vibrant structural colour in reflection. We demonstrate that light trapping within the nanostructures is the primary mechanism for colour generation. The use of planar back-reflector and polymer layers allows for less complex fabrication requirements and robust structures, but most significantly allows for the easy incorporation of two different metals for the back-reflector and the nanodiscs. The simplicity of the structure is also suitable for scalability. Combinations of gold, silver, aluminium and copper are considered, with wide colour gamuts observed as a function of the polymer layer thickness. The structural colours are also shown to be insensitive to the viewing angle. Structures of copper nanodiscs with an aluminium back-reflector produce the widest colour gamut. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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Review

Jump to: Research, Other

40 pages, 4508 KiB

Open AccessReview

Emergence of Impurity-Doped Nanocrystal Light-Emitting Diodes

by Dongxiang Luo, Lin Wang, Ying Qiu, Runda Huang and Baiquan Liu

Nanomaterials 2020, 10(6), 1226; https://doi.org/10.3390/nano10061226 - 24 Jun 2020

Cited by 14 | Viewed by 5594

Abstract

In recent years, impurity-doped nanocrystal light-emitting diodes (LEDs) have aroused both academic and industrial interest since they are highly promising to satisfy the increasing demand of display, lighting, and signaling technologies. Compared with undoped counterparts, impurity-doped nanocrystal LEDs have been demonstrated to possess [...] Read more.

In recent years, impurity-doped nanocrystal light-emitting diodes (LEDs) have aroused both academic and industrial interest since they are highly promising to satisfy the increasing demand of display, lighting, and signaling technologies. Compared with undoped counterparts, impurity-doped nanocrystal LEDs have been demonstrated to possess many extraordinary characteristics including enhanced efficiency, increased luminance, reduced voltage, and prolonged stability. In this review, recent state-of-the-art concepts to achieve high-performance impurity-doped nanocrystal LEDs are summarized. Firstly, the fundamental concepts of impurity-doped nanocrystal LEDs are presented. Then, the strategies to enhance the performance of impurity-doped nanocrystal LEDs via both material design and device engineering are introduced. In particular, the emergence of three types of impurity-doped nanocrystal LEDs is comprehensively highlighted, namely impurity-doped colloidal quantum dot LEDs, impurity-doped perovskite LEDs, and impurity-doped colloidal quantum well LEDs. At last, the challenges and the opportunities to further improve the performance of impurity-doped nanocrystal LEDs are described. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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22 pages, 6681 KiB

Open AccessReview

Graphene-Coated Nanowire Waveguides and Their Applications

by Da Teng, Kai Wang and Zhe Li

Nanomaterials 2020, 10(2), 229; https://doi.org/10.3390/nano10020229 - 28 Jan 2020

Cited by 45 | Viewed by 4931

Abstract

In recent years, graphene-coated nanowires (GCNWs) have attracted considerable research interest due to the unprecedented optical properties of graphene in terahertz (THz) and mid-infrared bands. Graphene plasmons in GCNWs have become an attractive platform for nanoscale applications in subwavelength waveguides, polarizers, modulators, nonlinear [...] Read more.

In recent years, graphene-coated nanowires (GCNWs) have attracted considerable research interest due to the unprecedented optical properties of graphene in terahertz (THz) and mid-infrared bands. Graphene plasmons in GCNWs have become an attractive platform for nanoscale applications in subwavelength waveguides, polarizers, modulators, nonlinear devices, etc. Here, we provide a comprehensive overview of the surface conductivity of graphene, GCNW-based plasmon waveguides, and applications of GCNWs in optical devices, nonlinear optics, and other intriguing fields. In terms of nonlinear optical properties, the focus is on saturable absorption. We also discuss some limitations of the GCNWs. It is believed that the research of GCNWs in the field of nanophotonics will continue to deepen, thus laying a solid foundation for its practical application. Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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Other

Jump to: Research, Review

1 pages, 163 KiB

Open AccessErratum

Erratum: Wang, D., et al. Self-Assembly Synthesis of the MoS₂/PtCo Alloy Counter Electrodes for High-Efficiency and Stable Low-Cost Dye-Sensitized Solar Cells. Nanomaterials 2020, 10, 1725

by Zhi Zeng, Dongbo Wang, Jinzhong Wang, Shujie Jiao, Yuewu Huang, Sixiang Zhao, Bingke Zhang, Mengyu Ma, Shiyong Gao, Xingguo Feng and Liancheng Zhao

Nanomaterials 2020, 10(11), 2217; https://doi.org/10.3390/nano10112217 - 6 Nov 2020

Cited by 1 | Viewed by 1592

Abstract

There is an error in the Funding statement of [...] Full article

(This article belongs to the Special Issue Low-Dimensional Nanomaterials for Photonics and Optoelectronics)

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