Graphene-Based Nanostructures and Optoelectronic Applications

A special issue of Nanomaterials (ISSN 2079-4991). This special issue belongs to the section "Synthesis, Interfaces and Nanostructures".

Deadline for manuscript submissions: closed (30 April 2020) | Viewed by 51700

Special Issue Editor

Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece
Interests: colloidal stability of carbon-based nanomaterials (carbon nanotubes, graphene); chemical functionalization of graphitic nanostructures; multifunctional graphene/polymer composite materials; semiconducting nanostructured assemblies as functional electrode components in optoelectronic applications
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Optoelectronic processes are taking place in devices, in which either an electric charge is used to generate light, such as in light emitting diodes and lasers, or light is used to generate electric current, such as in photovoltaic devices and photodetectors. Functional components of these devices, such as electrodes, involve a wide range of nanostructured materials. The exotic structural and conductive properties of two-dimensional graphitic nanostructures have created a scientific frenzy towards the integration of such materials in optoelectronic devices. The development of graphene-based electrode materials for optoelectronic devices is the key to widening their applicability in real-life applications.

This Special Issue addresses graphene-based nanomaterials for optoelectronic applications. I invite the scientific community to present the latest knowledge related to the aforementioned topics. All this gathered information will act as a spark towards the generation of new ideas, which are going to further develop the topic under study.

Dr. Dimitrios Tasis
Guest Editor

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Keywords

  • graphene derivatives
  • optoelectronics
  • light emitting diodes
  • lasers
  • photovoltaic cells
  • photodetectors
  • electrodes

Published Papers (13 papers)

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Research

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11 pages, 2573 KiB  
Article
Photo-Induced Doping in a Graphene Field-Effect Transistor with Inkjet-Printed Organic Semiconducting Molecules
by Nikita Nekrasov, Dmitry Kireev, Nejra Omerović, Aleksei Emelianov and Ivan Bobrinetskiy
Nanomaterials 2019, 9(12), 1753; https://doi.org/10.3390/nano9121753 - 10 Dec 2019
Cited by 5 | Viewed by 3221
Abstract
In this work, we report a novel method of maskless doping of a graphene channel in a field-effect transistor configuration by local inkjet printing of organic semiconducting molecules. The graphene-based transistor was fabricated via large-scale technology, allowing for upscaling electronic device fabrication and [...] Read more.
In this work, we report a novel method of maskless doping of a graphene channel in a field-effect transistor configuration by local inkjet printing of organic semiconducting molecules. The graphene-based transistor was fabricated via large-scale technology, allowing for upscaling electronic device fabrication and lowering the device’s cost. The altering of the functionalization of graphene was performed through local inkjet printing of N,N′-Dihexyl-3,4,9,10-perylenedicarboximide (PDI-C6) semiconducting molecules’ ink. We demonstrated the high resolution (about 50 µm) and accurate printing of organic ink on bare chemical vapor deposited (CVD) graphene. PDI-C6 forms nanocrystals onto the graphene’s surface and transfers charges via π–π stacking to graphene. While the doping from organic molecules was compensated by oxygen molecules under normal conditions, we demonstrated the photoinduced current generation at the PDI-C6/graphene junction with ambient light, a 470 nm diode, and 532 nm laser sources. The local (in the scale of 1 µm) photoresponse of 0.5 A/W was demonstrated at a low laser power density. The methods we developed open the way for local functionalization of an on-chip array of graphene by inkjet printing of different semiconducting organic molecules for photonics and electronics. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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11 pages, 3030 KiB  
Article
Synthesis of Nitrogen-Doped Graphene on Copper Nanowires for Efficient Thermal Conductivity and Stability by Using Conventional Thermal Chemical Vapor Deposition
by Minjeong Park, Seul-Ki Ahn, Sookhyun Hwang, Seongjun Park, Seonpil Kim and Minhyon Jeon
Nanomaterials 2019, 9(7), 984; https://doi.org/10.3390/nano9070984 - 07 Jul 2019
Cited by 4 | Viewed by 3158
Abstract
Cu nanowires (NWs) possess remarkable potential a slow-cost heat transfer material in modern electronic devices. However, Cu NWs with high aspect ratios undergo surface oxidation, resulting in performance degradation. A growth temperature of approximately <1000 °C is required for preventing the changing of [...] Read more.
Cu nanowires (NWs) possess remarkable potential a slow-cost heat transfer material in modern electronic devices. However, Cu NWs with high aspect ratios undergo surface oxidation, resulting in performance degradation. A growth temperature of approximately <1000 °C is required for preventing the changing of Cu NW morphology by the melting of Cu NWs at over 1000 °C. In addition, nitrogen (N)-doped carbon materials coated on Cu NWs need the formation hindrance of oxides and high thermal conductivity of Cu NWs. Therefore, we investigated the N-doped graphene-coated Cu NWs (NG/Cu NWs) to enhance both the thermal conductivity and oxidation stability of Cu NWs. The Cu NWs were synthesized through an aqueous method, and ethylenediamine with an amine group induced the isotropic growth of Cu to produce Cu NWs. At that time, the amine group could be used as a growth source for the N-doped graphene on Cu NWs. To grow an N-doped graphene without changing the morphology of Cu NWs, we report a double-zone growth process at a low growth temperature of approximately 600 °C. Thermal-interface material measurements were conducted on the NG/Cu NWs to confirm their applicability as heat transfer materials. Our results show that the synthesis technology of N-doped graphene on Cu NWs could promote future research and applications of thermal interface materials in air-stable flexible electronic devices. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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13 pages, 5245 KiB  
Article
Low-Power Graphene/ZnO Schottky UV Photodiodes with Enhanced Lateral Schottky Barrier Homogeneity
by Youngmin Lee, Deuk Young Kim and Sejoon Lee
Nanomaterials 2019, 9(5), 799; https://doi.org/10.3390/nano9050799 - 24 May 2019
Cited by 21 | Viewed by 4390
Abstract
The low-power, high-performance graphene/ZnO Schottky photodiodes were demonstrated through the direct sputter-growth of ZnO onto the thermally-cleaned graphene/SiO2/Si substrate at room temperature. Prior to the growth of ZnO, a thermal treatment of the graphene surface was performed at 280 °C for [...] Read more.
The low-power, high-performance graphene/ZnO Schottky photodiodes were demonstrated through the direct sputter-growth of ZnO onto the thermally-cleaned graphene/SiO2/Si substrate at room temperature. Prior to the growth of ZnO, a thermal treatment of the graphene surface was performed at 280 °C for 10 min in a vacuum to desorb chemical residues that may serve as trap sites at the interface between graphene and ZnO. The device clearly showed a rectifying behavior with the Schottky barrier of ≈0.61 eV and an ideality factor of 1.16. Under UV illumination, the device exhibited the excellent photoresponse characteristics in both forward and reverse bias regions. When illuminating UV light with the optical power density of 0.62 mW/cm2, the device revealed a high on/off current ratio of >103 even at a low bias voltage of 0.1 V. For the transient characteristics upon switching of UV light pulses, the device represented a fast and stable photoresponse (i.e., rise time: 0.16 s, decay time: 0.19 s). From the temperature-dependent current–voltage characteristics, such an outstanding photoresponse characteristic was found to arise from the enhanced Schottky barrier homogeneity via the thermal treatment of the graphene surface. The results suggest that the ZnO/graphene Schottky diode holds promise for the application in high-performance low-power UV photodetectors. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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10 pages, 3506 KiB  
Article
Tunable Graphene-Based Plasmon-Induced Transparency Based on Edge Mode in the Mid-Infrared Region
by Heng Xu, Zhaojian Zhang, Shangwu Wang, Yun Liu, Jingjing Zhang, Dingbo Chen, Jianming Ouyang and Junbo Yang
Nanomaterials 2019, 9(3), 448; https://doi.org/10.3390/nano9030448 - 17 Mar 2019
Cited by 10 | Viewed by 2636
Abstract
A monolayer-graphene-based concentric-double-rings (CDR) structure is reported to achieve broadband plasmon-induced transparency (PIT) on the strength of edge mode in the mid-infrared regime. The theoretical analysis and simulation results reveal that the structure designed here has two plasmonic resonance peaks at 39.1 and [...] Read more.
A monolayer-graphene-based concentric-double-rings (CDR) structure is reported to achieve broadband plasmon-induced transparency (PIT) on the strength of edge mode in the mid-infrared regime. The theoretical analysis and simulation results reveal that the structure designed here has two plasmonic resonance peaks at 39.1 and 55.4 THz, and a transparency window with high transmission amplitude at the frequency of 44.1 THz. Based on the edge mode coupling between neighbor graphene ribbons, PIT phenomenon is produced through the interference between different (bright and dark) modes. The frequency and bandwidth of the transparency window and slow light time could be effectively adjusted and controlled via changing geometrical parameters of graphene or applying different gate voltages. Additionally, this structure is insensitive to the polarization and incident angle. This work has potential application on the optical switches and slow light modulators. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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15 pages, 4792 KiB  
Article
A Facile Method for Batch Preparation of Electrochemically Reduced Graphene Oxide
by Yi-Fang Hung, Chia Cheng, Chun-Kai Huang and Chii-Rong Yang
Nanomaterials 2019, 9(3), 376; https://doi.org/10.3390/nano9030376 - 05 Mar 2019
Cited by 20 | Viewed by 2991
Abstract
The electrochemical reduction of graphene oxide (GO) is an environmentally friendly and energy-saving method for improving the characteristics of GO. However, GO films must be coated on the cathode electrode in advance when usingthis technique. Thus, the formed electrochemically reduced GO (ERGO) films [...] Read more.
The electrochemical reduction of graphene oxide (GO) is an environmentally friendly and energy-saving method for improving the characteristics of GO. However, GO films must be coated on the cathode electrode in advance when usingthis technique. Thus, the formed electrochemically reduced GO (ERGO) films can be used only as sensing or conductive materials in devices because mass production of the flakes is not possible. Therefore, this study proposes a facile electrochemical reduction technique. In this technique, GO flakes can be directly used as reduced materials, and no GO films are required in advance. A 0.1 M phosphate buffered saline solution was used as the electrolyte, which is a highly safe chemical agent. Experimental results revealed that the as-prepared GO flakes were electrochemically reduced to form ERGO flakes by using a −10 V bias for 8 h. The ratio of the D-band and G-band feature peaks was increased from 0.86 to 1.12, as revealed by Raman spectroscopy, the π-π stacking interaction operating between the ERGO and GO has been revealed by UV-Vis absorption spectroscopy, and the C–O ratio was increased from 2.02 to 2.56, as indicated by X-ray photoelectron spectroscopy. The electrical conductivity of the ERGO film (3.83 × 10−1 S·cm−1) was considerably better than that of the GO film (7.92 × 10−4 S·cm−1). These results demonstrate that the proposed electrochemical reduction technique can provide high-quality ERGO flakes and that it has potential for large-scale production. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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17 pages, 3668 KiB  
Article
Graphene-Supported Thin Metal Films for Nanophotonics and Optoelectronics
by Dmitry I. Yakubovsky, Yury V. Stebunov, Roman V. Kirtaev, Kirill V. Voronin, Artem A. Voronov, Aleksey V. Arsenin and Valentyn S. Volkov
Nanomaterials 2018, 8(12), 1058; https://doi.org/10.3390/nano8121058 - 15 Dec 2018
Cited by 16 | Viewed by 5485
Abstract
Graphene-metal hybrid nanostructures have attracted considerable attention due to their potential applications in nanophotonics and optoelectronics. The output characteristics of devices based on such nanostructures largely depend on the properties of the metals. Here, we study the optical, electrical and structural properties of [...] Read more.
Graphene-metal hybrid nanostructures have attracted considerable attention due to their potential applications in nanophotonics and optoelectronics. The output characteristics of devices based on such nanostructures largely depend on the properties of the metals. Here, we study the optical, electrical and structural properties of continuous thin gold and copper films grown by electron beam evaporation on monolayer graphene transferred onto silicon dioxide substrates. We find that the presence of graphene has a significant effect on optical losses and electrical resistance, both for thin gold and copper films. Furthermore, the growth kinetics of gold and copper films vary greatly; in particular, we found here a significant dependence of the properties of thin copper films on the deposition rate, unlike gold films. Our work provides new data on the optical properties of gold and copper, which should be considered in modeling and designing devices with graphene-metal nanolayers. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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11 pages, 2811 KiB  
Article
Size Fractionation of Fluorescent Graphene Quantum Dots Using a Cross-Flow Membrane Filtration System
by Sang-Gu Yim, Yong Jin Kim, Ye-Eun Kang, Byung Kee Moon, Eun Sang Jung and Seung Yun Yang
Nanomaterials 2018, 8(11), 959; https://doi.org/10.3390/nano8110959 - 21 Nov 2018
Cited by 8 | Viewed by 4469
Abstract
Graphene quantum dots (GQDs) have received great attention as optical agents because of their low toxicity, stable photoluminescence (PL) in moderate pH solutions, and size-dependent optical properties. Although many synthetic routes have been proposed for producing GQD solutions, the broad size distribution in [...] Read more.
Graphene quantum dots (GQDs) have received great attention as optical agents because of their low toxicity, stable photoluminescence (PL) in moderate pH solutions, and size-dependent optical properties. Although many synthetic routes have been proposed for producing GQD solutions, the broad size distribution in GQD solutions limits its use as an efficient optical agent. Here, we present a straightforward method for size fractionation of GQDs dispersed in water using a cross-flow filtration system and a track-etched membrane with cylindrical uniform nanopores. The GQD aqueous suspension, which primarily contained blue-emitting GQDs (B-GQDs) and green-emitting GQDs (G-GQDs), was introduced to the membrane in tangential flow and was fractionated with a constant permeate flow of about 800 L m−2 h−1 bar−1. After filtration, we observed a clear blue PL spectrum from the permeate side, which can be attributed to selective permeation of relatively small B-GQDs. The process provided a separation factor (B-GQDs/G-GQDs) of 0.74. In the cross-flow filtration system, size-dependent permeation through cylindrical nanochannels was confirmed by simulation. Our results demonstrate a feasible method facilitating size fractionation of two-dimensional nanostructures using a cross-flow membrane filtration system. Since membrane filtration is simple, cost-effective, and scalable, our approach can be applied to prepare a large amount of size-controlled GQDs required for high performance opto-electronics and bio-imaging applications. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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10 pages, 1951 KiB  
Article
A Broadband Phototransistor Based on Three-Dimensional Reduced Graphene Oxide Foam
by Yifan Li, Yating Zhang, Yu Yu, Zhiliang Chen, Lufan Jin, Mingxuan Cao, Haitao Dai and Jianquan Yao
Nanomaterials 2018, 8(11), 913; https://doi.org/10.3390/nano8110913 - 06 Nov 2018
Cited by 3 | Viewed by 2697
Abstract
Three-dimensional (3D) cross-linked polymer-like reduced graphene oxide foams (rGOFs) with a seamlessly continuous graphene network, exhibit high photoresponsive and conductivity and have received much attention regarding solar cells and supercapacitors. However, little attention has been paid to photodetection applications of 3D rGOFs. Here [...] Read more.
Three-dimensional (3D) cross-linked polymer-like reduced graphene oxide foams (rGOFs) with a seamlessly continuous graphene network, exhibit high photoresponsive and conductivity and have received much attention regarding solar cells and supercapacitors. However, little attention has been paid to photodetection applications of 3D rGOFs. Here we report a novel broadband phototransistor based on metal-3D GFs-metal, which exhibits a high light absorption and a wide spectra response ranging at least from 400 to 1600 nm wavelength with a maximum photoresponsivity of 10 mA/W at 400 nm. In particular, stable and reproducible photocurrent cycles are achieved under different light blue light (405 nm), green light (532 nm), and NIR (808 nm) irradiations. Moreover, the device displays a typical transistor characteristic with a rapid response time of 18 ms at under 532 nm irradiation. The excellent performances indicate 3D rGOF as a promising candidate for future photodetection application. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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12 pages, 4376 KiB  
Article
Characteristics of Graphene Oxide Films Reduced by Using an Atmospheric Plasma System
by Chii-Rong Yang, Shih-Feng Tseng and Yu-Ting Chen
Nanomaterials 2018, 8(10), 802; https://doi.org/10.3390/nano8100802 - 08 Oct 2018
Cited by 15 | Viewed by 3790
Abstract
The chemical oxidation method can be used to mass-produce graphene oxides (GOs) from highly oriented pyrolytic graphite. However, numerous oxygen-containing functional groups (hydroxyl, epoxy, carbonyl, etc.) exist in typical GO surfaces, resulting in serious electrical losses. Hence, GO must be processed into reduced [...] Read more.
The chemical oxidation method can be used to mass-produce graphene oxides (GOs) from highly oriented pyrolytic graphite. However, numerous oxygen-containing functional groups (hydroxyl, epoxy, carbonyl, etc.) exist in typical GO surfaces, resulting in serious electrical losses. Hence, GO must be processed into reduced graphene oxide (rGO) by the removal of most of the oxygen-containing functional groups. This research concentrates on the reduction efficiency of GO films that are manufactured using atmospheric-pressure and continuous plasma irradiation. Before and after sessions of plasma irradiation with various irradiation times, shelters, and working distances, the surface, physical, and electrical characteristics of homemade GO and rGO films are measured and analyzed. Experimental results showed that the sheet resistance values of rGO films with silicon or quartz shelters were markedly lower than those of GO films because the rGO films were mostly deprived of oxygen-containing functional groups. The lowest sheet resistance value and the largest carbon-to-oxygen ratio of typical rGO films were approximately 90 Ω/sq and 1.522, respectively. The intensity of the C–O bond peak in typical rGO films was significantly lower than that in GO films. Moreover, the intensity of the C–C bond peak in typical rGO films was considerably higher than that in GO films. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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11 pages, 3149 KiB  
Article
Actively Tunable Terahertz Switches Based on Subwavelength Graphene Waveguide
by Zhongyi Guo, Xiaoru Nie, Fei Shen, Hongping Zhou, Qingfeng Zhou, Jun Gao and Kai Guo
Nanomaterials 2018, 8(9), 665; https://doi.org/10.3390/nano8090665 - 26 Aug 2018
Cited by 22 | Viewed by 3158
Abstract
As a new field of optical communication technology, on-chip graphene devices are of great interest due to their active tunability and subwavelength scale. In this paper, we systematically investigate optical switches at frequency of 30 THz, including Y-branch (1 × 2), X-branch (2 [...] Read more.
As a new field of optical communication technology, on-chip graphene devices are of great interest due to their active tunability and subwavelength scale. In this paper, we systematically investigate optical switches at frequency of 30 THz, including Y-branch (1 × 2), X-branch (2 × 2), single-input three-output (1 × 3), two-input three-output (2 × 3), and two-input four-output (2 × 4) switches. In these devices, a graphene monolayer is stacked on the top of a PMMA (poly methyl methacrylate methacrylic acid) dielectric layer. The optical response of graphene can be electrically manipulated; therefore, the state of each channel can be switched ON and OFF. Numerical simulations demonstrate that the transmission direction can be well manipulated in these devices. In addition, the proposed devices possess advantages of appropriate ON/OFF ratios, indicating the good performance of graphene in terahertz switching. These devices provide a new route toward terahertz optical switching. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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11 pages, 6218 KiB  
Article
Electrically Tunable Broadband Terahertz Absorption with Hybrid-Patterned Graphene Metasurfaces
by Longfang Ye, Xin Chen, Guoxiong Cai, Jinfeng Zhu, Na Liu and Qing Huo Liu
Nanomaterials 2018, 8(8), 562; https://doi.org/10.3390/nano8080562 - 24 Jul 2018
Cited by 55 | Viewed by 4684
Abstract
We numerically demonstrate a broadband terahertz (THz) absorber that is based on a hybrid-patterned graphene metasurface with excellent properties of polarization insensitivity, wide-angle, and active tunability. Our design is made up of a single-layer graphene with periodically arranged hybrid square/disk/loop patterns on a [...] Read more.
We numerically demonstrate a broadband terahertz (THz) absorber that is based on a hybrid-patterned graphene metasurface with excellent properties of polarization insensitivity, wide-angle, and active tunability. Our design is made up of a single-layer graphene with periodically arranged hybrid square/disk/loop patterns on a multilayer structure. We find that broadband absorption with 90% terahertz absorbance and the fractional bandwidth of 84.5% from 1.38 THz to 3.4 THz can be achieved. Because of the axisymmetric configuration, the absorber demonstrates absolute polarization independence for both transverse electric (TE) and transverse magnetic (TM) polarized terahertz waves under normal incidence. We also show that a bandwidth of 60% absorbance still remains 2.7 THz, ranging from 1.3 THz to 4 THz, for a wide incident angle ranging from 0° to 60°. Finally, we find that by changing the graphene Fermi energy from 0.7 eV to 0 eV, the absorbance of the absorbers can be easily tuned from more than 90% to lower than 20%. The proposed absorber may have promising applications in terahertz sensing, detecting, imaging, and cloaking. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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18 pages, 2788 KiB  
Article
In Vitro Cytotoxicity and Morphological Assessments of GO-ZnO against the MCF-7 Cells: Determination of Singlet Oxygen by Chemical Trapping
by Fozia Shaheen, Muhammad Hammad Aziz, Mahvish Fatima, Muhammad Ajmal Khan, Faisal Ahmed, Riaz Ahmad, Muhammad Ashfaq Ahmad, Turki S. Alkhuraiji, Muhammad Waseem Akram, Rizwan Raza and Syed Mansoor Ali
Nanomaterials 2018, 8(7), 539; https://doi.org/10.3390/nano8070539 - 18 Jul 2018
Cited by 26 | Viewed by 4665
Abstract
Graphene-based materials have attracted considerable interest owing to their distinctive characteristics, such as their biocompatibility in terms of both their physical and intrinsic chemical properties. The use of nanomaterials with graphene as a biocompatible agent has increased due to an uptick in dedication [...] Read more.
Graphene-based materials have attracted considerable interest owing to their distinctive characteristics, such as their biocompatibility in terms of both their physical and intrinsic chemical properties. The use of nanomaterials with graphene as a biocompatible agent has increased due to an uptick in dedication from biomedical investigators. Here, GO-ZnO was characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), ultraviolet-visible (UV-Vis) spectroscopy, energy dispersive X-ray analysis (EDAX), and Raman spectroscopy for structural, morphological, and elemental analysis. The toxic extent of GO-ZnO was noted by a methyl-thiazole-tetrazolium (MTT), while cellular morphology was observed towards the MCF-7 cells using an inverted microscope at magnification 40×. The cytotoxic effect of GO-ZnO investigated the cell viability reduction in a dose-dependent manner, as well as prompted the cell demise/destruction in an apoptotic way. Moreover, statistical analysis was performed on the experimental outcomes, with p-values < 0.05 kept as significant to elucidate the results. The generation of reactive oxygen species (ROS) demonstrated the potential applicability of graphene in tumor treatment. These key results attest to the efficacy of GO-ZnO nanocomposites as a substantial candidate for breast malignancy treatment. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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Review

Jump to: Research

20 pages, 2036 KiB  
Review
Graphene-Based Perfect Absorption Structures in the Visible to Terahertz Band and Their Optoelectronics Applications
by Chucai Guo, Jianfa Zhang, Wei Xu, Ken Liu, Xiaodong Yuan, Shiqiao Qin and Zhihong Zhu
Nanomaterials 2018, 8(12), 1033; https://doi.org/10.3390/nano8121033 - 12 Dec 2018
Cited by 61 | Viewed by 5281
Abstract
Graphene has unique properties which make it an ideal material for photonic and optoelectronic devices. However, the low light absorption in monolayer graphene seriously limits its practical applications. In order to greatly enhance the light absorption of graphene, many graphene-based structures have been [...] Read more.
Graphene has unique properties which make it an ideal material for photonic and optoelectronic devices. However, the low light absorption in monolayer graphene seriously limits its practical applications. In order to greatly enhance the light absorption of graphene, many graphene-based structures have been developed to achieve perfect absorption of incident waves. In this review, we discuss and analyze various types of graphene-based perfect absorption structures in the visible to terahertz band. In particular, we review recent advances and optoelectronic applications of such structures. Indeed, the graphene-based perfect absorption structures offer the promise of solving the key problem which limits the applications of graphene in practical optoelectronic devices. Full article
(This article belongs to the Special Issue Graphene-Based Nanostructures and Optoelectronic Applications)
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