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In-Situ Catalytic Preparation of Two-Dimensional BCN/Graphene Composite for Anti-Corrosion Application. Catalysts 2022. [DOI: 10.3390/catal12121618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In-situ catalytic growth of two-dimensional materials shows great potential for metal surface protection because of the impermeability and strong interaction of the materials with metal surfaces. Two-dimensional hexagonal boron-carbon nitrogen (h-BCN) is composed of alternating boron, carbon, and nitrogen atoms in a two-dimensional honeycomb lattice, which is similar to graphene. The corrosion caused by defects such as grain boundary of two-dimensional materials can be weakened by dislocation overlap via the transfer method. However, two-dimensional composite films prepared using the transfer method have problems, such as the introduction of impurities and poor adhesion, which limit their corrosion resistance. In this study, a layer of BCN/Gr two-dimensional composite was directly grown on the surface of copper foil using the CVD in-situ catalysis method, and its anti-corrosion performance was characterized by electrochemical and salt spray experiments. The results showed that the directly grown two-dimensional composite had better adhesion to the substrate and the advantage of grain boundary dislocation, thus showing a better anti-corrosion capability.
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52
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Novikova A, Karabchevsky A. Green Extraction of Graphene from Natural Mineral Shungite. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:4356. [PMID: 36558210 PMCID: PMC9787502 DOI: 10.3390/nano12244356] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2022] [Revised: 12/01/2022] [Accepted: 12/05/2022] [Indexed: 06/17/2023]
Abstract
Conventional fabrication methods to produce graphene are cumbersome, expensive, and not ecologically friendly. This is due to the fact that the processing of a large volume of raw materials requires large amounts of acids and alkalis which, in turn, require special disposal. Therefore, it is necessary to develop new technologies or to refine existing ones for the production of graphene-and to create new, ecologically-safe and effective methods. Here, we utilized physical sonication to extract graphene films from natural mineral shungite rock. From our study of the structure of shungite by Raman spectrometry and X-ray phase analysis, we found that shungite is characterized by graphite-like mineral structures. Transmission electron microscopy images obtained from the processed material revealed graphene films-with surfaces as small as 200 nanometers long and several layers wide. Our green method of fabicating graphene can be widely used in a variety of fields, from electro-optics to ecology, to list a few.
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53
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Choi J, Park SG, Choi YJ, Baek SM, Kim HJ, Kim Y, Im KS, An SJ. Viscosity-Controllable Graphene Oxide Colloids Using Electrophoretically Deposited Graphene Oxide Sheets. MICROMACHINES 2022; 13:2157. [PMID: 36557456 PMCID: PMC9784829 DOI: 10.3390/mi13122157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
Graphene oxide (GO) is one of the interesting ink materials owing to its fascinating properties, such as high dissolubility in water and high controllable electric properties. For versatile printing application, the viscosity of GO colloids should be controlled in order to meet the specific process requirements. Here, we report on the relatively rapid fabrication of viscosity-increased GO (VIGO) colloids mixed with electrophoretically deposited GO sheets (EPD-GO). As the GO colloid concentration, applied voltage, and deposition time increase, the viscosity of the GO colloids becomes high. The reason for the improved viscosity of GO colloids is because EPD-GO has parallel stacked GO sheets. The GO and VIGO colloids are compared and characterized using various chemical and structural analyzers. Consequently, our simple and fast method for the fabrication of GO colloids with enhanced viscosity can be used for producing inks for flexible and printed electronics.
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Affiliation(s)
- Jinseok Choi
- Department of Advanced Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea
| | - Seong-Gyu Park
- Department of Advanced Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea
| | - Yeo-Jin Choi
- Department of Advanced Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea
| | - Seung-Mun Baek
- Department of Advanced Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea
| | - Han-Jung Kim
- Nano Electronic Materials and Components Research Center, Gumi Electronics and Information Technology Research Institute, Gumi 39171, Republic of Korea
| | - Yoonkap Kim
- Nano Electronic Materials and Components Research Center, Gumi Electronics and Information Technology Research Institute, Gumi 39171, Republic of Korea
| | - Ki-Sik Im
- Department of Green Semiconductor System, Daegu Campus, Korea Polytechnics, Daegu 41765, Republic of Korea
| | - Sung-Jin An
- Department of Advanced Materials Science and Engineering, Kumoh National Institute of Technology, Gumi 39177, Republic of Korea
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54
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Checking the Efficiency of a Magnetic Graphene Oxide–Titania Material for Catalytic and Photocatalytic Ozonation Reactions in Water. Catalysts 2022. [DOI: 10.3390/catal12121587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
An easily recoverable photo-catalyst in solid form has been synthesized and applied in catalytic ozonation in the presence of primidone. Maghemite, graphene oxide and titania (FeGOTi) constituted the solid. Additionally, titania (TiO2) and graphene oxide–titania (GOTi) catalysts were also tested for comparative reasons. The main characteristics of FeGOTi were 144 m2/g of surface area; a 1.29 Raman D and G band intensity ratio; a 26-emu g−1 magnetic moment; maghemite, anatase and brookite main crystalline forms; and a 1.83 eV band gap so the catalyst can absorb up to the visible red region (677 nm). Single ozonation, photolysis, photolytic ozonation (PhOz), catalytic ozonation (CatOz) and photocatalytic ozonation (PhCatOz) were applied to remove primidone. In the presence of ozone, the complete removal of primidone was experienced in less than 15 min. In terms of mineralization, the best catalyst was GOTi in the PhCatOz processes (100% mineralization in 2 h). Meanwhile, the FeGOTi catalyst was the most efficient in CatOz. FeGOTi led, in all cases, to the highest formation of HO radicals and the lowest ozone demand. The reuse of the FeGOTi catalyst led to some loss of mineralization efficacy after four runs, likely due to C deposition, the small lixiviation of graphene oxide and Fe oxidation.
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55
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Consecutive Ink Writing of Conducting Polymer and Graphene Composite Electrodes for Foldable Electronics-Related Applications. Polymers (Basel) 2022; 14:polym14235294. [PMID: 36501688 PMCID: PMC9736600 DOI: 10.3390/polym14235294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/09/2022] Open
Abstract
For foldable electronic devices of the future, most components should have very good flexibility and reliability to maintain electrical properties even under repeated deformation. In this study, two types of inks for conducting polymer and graphene were simultaneously printed on flexible plastic substrates via the newly developed consecutive ink writing (CIW) process for the formation of composite electrodes of foldable electronic devices. To consecutively print conducting polymer ink and graphene ink, a conventional three-dimensional (3D) printer was modified by installing two needles in the printer head, and the two inks were printed through the nozzle in the same route with a time interval. By adjusting several printing conditions (ink concentration, printing parameters, printing time intervals between the two inks, etc.), various structures of composite electrodes, such as layered or fused 2D or 3D structures were developed on the glass substrate. Furthermore, by changing the printing order of the two inks and 3D printer bed temperature, the composite electrodes with a higher printing resolution were successfully printed on the flexible polyimide substrate. The printed composite electrodes via CIW process exhibit the lowest surface electrical resistance of 0.9 kΩ and high flexibility, and stable resistance values were maintained after 1000 cycles of the folding test. Consequently, the CIW process developed in this study applies to the production of the electrical parts and components for various flexible devices, such as foldable and wearable electronics.
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56
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Zhou Q, Wang L, Ju W, Miao H, Ye S, Liu Y. Influence of the co-doping and line-doping on the quantum capacitance of stanene for supercapacitor electrodes. Chem Phys Lett 2022. [DOI: 10.1016/j.cplett.2022.140123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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57
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Xu X, Yin Y, Yao M, Yin X, Gao F, Wu Y, Chen C, Wang F, Zhang D. Three-Dimensional Polymer Variable Optical Attenuator Based on Vertical Multimode Interference with Graphene Heater. MICROMACHINES 2022; 13:2116. [PMID: 36557416 PMCID: PMC9781668 DOI: 10.3390/mi13122116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/24/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
Low-power-consumption optical devices are crucial for large-scale photonic integrated circuits (PICs). In this paper, a three-dimensional (3D) polymer variable optical attenuator (VOA) is proposed. For monolithic integration of silica and polymer-based planar lightwave circuits (PLCs), the vertical VOA is inserted between silica-based waveguides. Optical and thermal analyses are performed through the beam propagation method (BPM) and finite-element method (FEM), respectively. A compact size of 3092 μm × 4 μm × 7 μm is achieved with a vertical multimode interference (MMI) structure. The proposed VOA shows an insertion loss (IL) of 0.58 dB and an extinction ratio (ER) of 21.18 dB. Replacing the graphene heater with an aluminum (Al) electrode, the power consumption is decreased from 29.90 mW to 21.25 mW. The rise and fall time are improved to 353.85 μs and 192.87 μs, respectively. The compact and high-performance VOA shows great potential for a variety of applications, including optical communications, integrated optics, and optical interconnections.
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Affiliation(s)
- Xinru Xu
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Yuexin Yin
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Mengke Yao
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Xiaojie Yin
- State Key Laboratory of Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
- Shijia Photons Technology, Hebi 458030, China
| | - Feifei Gao
- Shijia Photons Technology, Hebi 458030, China
| | - Yuanda Wu
- College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changming Chen
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Fei Wang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
| | - Daming Zhang
- State Key Laboratory of Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, China
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58
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Ali M, Dong Y, Lv J, Guo H, Abid Anwar M, Tian F, Shahzad K, Liu W, Yu B, Bodepudi SC, Xu Y. In-Situ Monitoring of Reciprocal Charge Transfer and Losses in Graphene-Silicon CCD Pixels. SENSORS (BASEL, SWITZERLAND) 2022; 22:9341. [PMID: 36502042 PMCID: PMC9735458 DOI: 10.3390/s22239341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/23/2022] [Accepted: 11/24/2022] [Indexed: 06/17/2023]
Abstract
Charge-coupled devices (CCD) allow imaging by photodetection, charge integration, and serial transfer of the stored charge packets from multiple pixels to the readout node. The functionality of CCD can be extended to the non-destructive and in-situ readout of the integrated charges by replacing metallic electrodes with graphene in the metal-oxide-semiconductors (MOS) structure of a CCD pixel. The electrostatic capacitive coupling of graphene with the substrate allows the Fermi level tuning that reflects the integrated charge density in the depletion well. This work demonstrates the in-situ monitoring of the serial charge transfer and interpixel transfer losses in a reciprocating manner between two adjacent Gr-Si CCD pixels by benefitting the electrostatic and gate-to-gate couplings. We achieved the maximum charge transfer efficiency (CTE) of 92.4%, which is mainly decided by the inter-pixel distance, phase clock amplitudes, switching slopes, and density of surface defects. The discussion on overcoming transfer losses and improving CTE by realizing a graphene-electron multiplication CCD is also presented. The proof of the concept of the in-situ readout of the out-of-plane avalanche in a single Gr-Si CCD pixel is also demonstrated, which can amplify the photo packet in a pre-transfer manner.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Bin Yu
- Correspondence: (B.Y.); (S.C.B.); (Y.X.)
| | | | - Yang Xu
- Correspondence: (B.Y.); (S.C.B.); (Y.X.)
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59
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Chianese F, Aversa L, Verucchi R, Cassinese A. Molecular Doping of CVD-Graphene Surfaces by Perfluoroalkyl-Substituted Perylene Diimides Derivatives. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:4239. [PMID: 36500862 PMCID: PMC9737924 DOI: 10.3390/nano12234239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 11/22/2022] [Accepted: 11/25/2022] [Indexed: 06/17/2023]
Abstract
Non-covalent π-π and dipolar interactions with small aromatic molecules have been widely demonstrated to be a valid option to tune graphene work functions without adding extrinsic scattering centers for charge carriers. In this work, we investigated the interaction between a CVD-graphene monolayer and a thermally evaporated sub-monolayer and the following few-layer thin films of similar perylene diimide derivatives: PDI8-CN2 and PDIF-CN2. The molecular influence on the graphene work function was estimated by XPS and UPS analysis and by investigating the surface potentials via scanning Kelvin probe force microscopy. The perfluorinated decoration and the steric interaction in the early stages of the film growth determined a positive work function shift as high as 0.7 eV in the case of PDIF-CN2, with respect to the value of 4.41 eV for the intrinsic graphene. Our results unambiguously highlight the absence of valence band shifts in the UPS analysis, indicating the prevalence of dipolar interactions between the graphene surface and the organic species enhanced by the presence of the fluorine-enriched moieties.
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Affiliation(s)
- Federico Chianese
- Dipartimento di Fisica, Università Degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy
- CNR-SPIN, Unità di Napoli, Piazzale Tecchio 80, 80125 Napoli, Italy
| | - Lucrezia Aversa
- Institute of Materials for Electronics and Magnetism, CNR-IMEM, FBK Trento Unit, Via alla Cascata 56/C, 38123 Trento, Italy
| | - Roberto Verucchi
- Institute of Materials for Electronics and Magnetism, CNR-IMEM, FBK Trento Unit, Via alla Cascata 56/C, 38123 Trento, Italy
| | - Antonio Cassinese
- Dipartimento di Fisica, Università Degli Studi di Napoli Federico II, Piazzale Tecchio 80, 80125 Napoli, Italy
- CNR-SPIN, Unità di Napoli, Piazzale Tecchio 80, 80125 Napoli, Italy
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60
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Design of Bimetallic PtFe-Based Reduced Graphene Oxide as Efficient Catalyst for Oxidation Reduction Reaction. Catalysts 2022. [DOI: 10.3390/catal12121528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Abstract
Oxygen reduction reaction (ORR) is a very important reaction that occurs at the cathodic side in proton exchange membrane fuel cells (PEMFCs). The high cost associated with frequently used Pt-based electrocatalysts for ORR limits the commercialization of PEMFCs. Through bifunctional and electronic effects, theoretical calculations have proved that alloying Pt with a suitable transition metal is likely to improve ORR mass activity when compared to Pt-alone systems. Herein, we demonstrate the preparation of bimetallic Pt–Fe nanoparticles supported on reduced graphene oxide sheets (RGOs) via a simple surfactant-free chemical reduction method. The present method produces PtFe/RGO catalyst particles with a 3.2 nm diameter without agglomeration. PtFe/RGO showed a noticeable positive half-wave potential (0.503 V vs. Ag/AgCl) compared with a commercial Pt/C catalyst (0.352 V vs. Ag/AgCl) with minimal Pt-loading on a glassy carbon electrode. Further, PtFe/RGO showed a higher ORR mass activity of 4.85 mA/cm2-geo compared to the commercial Pt/C (3.60 mA/cm2-geo). This work paves the way for designing noble−transition metal alloy electrocatalysts on RGO supports as high-performance electrocatalysts for ORR application.
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61
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Kang D, Kim SH, Shin D, Oh JT, Kim MG, Lee PC. Hygroscopic Behavior of Polypropylene Nanocomposites Filled with Graphene Functionalized by Alkylated Chains. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12234130. [PMID: 36500753 PMCID: PMC9740230 DOI: 10.3390/nano12234130] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 05/27/2023]
Abstract
Owing to stringent international environmental and fuel efficiency requirements for lightweight automotive systems, polymer composites have attracted widespread attention. Polypropylene (PP) is a widely employed commercial polymer because of its lightweight and low cost. In this study, PP nanocomposites were fabricated to reduce the moisture absorption of PP composites in automotive headlamp housings. Alkylated chemically modified graphene (CMG-R) was synthesized to reduce the surface hydrophilicity of graphene and increase compatibility with the PP matrix. Fourier transform-infrared spectroscopy and scanning electron microscopy were performed to analyze the nanofillers. X-ray diffraction was performed to determine the interlayer spacing of the nanofiller resulting from surface treatment. Differential scanning calorimetry was used to analyze the crystallinity of the nanocomposites. The results indicated that the improved hydrophobicity of the nanofiller due to alkylation reduced the maximum moisture absorption of the PP nanocomposites by 15% compared to PP composites. The findings of this study are useful for reducing fogging in automotive headlamps.
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Affiliation(s)
- Dongwoo Kang
- Chemical Materials R&D Department, Korea Automotive Technology Institute, Cheonan-si 31214, Republic of Korea
| | - Sung Hee Kim
- School of Chemical Engineering, Sungkyunkwan University, Suwon-si 16419, Republic of Korea
| | - Donghyeok Shin
- R&D Center, Woosung Chemical Co., Ltd., Cheonan-si 31214, Republic of Korea
| | - Ji Taek Oh
- R&D Center, BESTGRAPHENE Co., Ltd., Yeoju-si 12616, Republic of Korea
| | - Myeong-Gi Kim
- R&D Center, BESTGRAPHENE Co., Ltd., Yeoju-si 12616, Republic of Korea
| | - Pyoung-Chan Lee
- Chemical Materials R&D Department, Korea Automotive Technology Institute, Cheonan-si 31214, Republic of Korea
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62
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Preparation of Graphene Oxide-Maghemite-Chitosan Composites for the Adsorption of Europium Ions from Aqueous Solutions. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27228035. [PMID: 36432137 PMCID: PMC9694936 DOI: 10.3390/molecules27228035] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/11/2022] [Accepted: 11/16/2022] [Indexed: 11/22/2022]
Abstract
The adsorption of Eu(III) on composites synthesised from graphene oxide (GO), maghemite (MGH), and chitosan (CS) has been studied using different approaches. The physicochemical and morphological characteristics of the composites GO-MGH, GO-CS, GO-MGH-CS I, II, and III were determined by XRD, Mössbauer spectroscopy, FTIR, Raman spectroscopy, and TEM. According to the results of batch experiments, the maximum experimental adsorption capacity was 52, 54, 25, 103, and 102 mg/g for GO-MGH, GO-CS, GO-MGH-CS I, II, and III, respectively. The data obtained are in better agreement with the Langmuir, pseudo-second-order, and pseudo-first-order models only for GO-MGH. Thus, the adsorption of Eu(III) on the composites was a favourable, monolayer, and occurred at homogeneous sites. The nature of adsorption is chemical and, in the case of GO-MGH, physical. Tests of the composites in natural waters showed a high removal efficiency for Eu(III), Pu(IV), and Am(III), ranging from 74 to 100%. The ANFIS model has quite good predictive ability, as shown by the values for R2, MSE, SSE, and ARE. The GO-MGH-CS composites with the high adsorption capacity could be promising candidates for the removal of Eu(III) and the pre-concentration of Pu(IV) and Am(III) from natural waters.
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63
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Esencan Türkaslan B, Çelik AK, Dalbeyler A, Fantuzzi N. The Effect of Different Morphologies of WO 3/GO Nanocomposite on Photocatalytic Performance. MATERIALS (BASEL, SWITZERLAND) 2022; 15:8019. [PMID: 36431504 PMCID: PMC9695636 DOI: 10.3390/ma15228019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
Tungsten trioxide/graphene oxide (WO3/GO) nanocomposites have been successfully synthesized using in situ and ex situ chemical approaches. Graphite and tungsten carbide (WC) were employed to perform in situ synthesis, and WO3 and GO were employed to perform the ex situ synthesis of WO3/GO nanocomposites. GO, which was required for ex situ synthesis, is synthesized via the modified and improved Hummers method. XRD, SEM/EDS, and FTIR are used for the characterization of the nanocomposite. From the XRD of the WO3/GO nanocomposites, it was observed that WO3 distributed uniformly on graphene oxide sheets or was incorporated between the sheets. The photocatalytic activities of WO3/GO nanocomposites were evaluated by methylene blue (MB) adsorption and visible light photocatalytic degradation activities by UV-vis spectroscopy. The results showed that the efficiency of the photocatalytic activity of the nanocomposite depends on different synthesis methods and the morphology resulting from the changed method. WO3/GO nanocomposites synthesized by both methods exhibited much higher photocatalytic efficiencies than pure WO3, and the best degradation efficiencies for MB was 96.30% for the WO3/GO in situ synthesis nanocomposite.
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Affiliation(s)
- Banu Esencan Türkaslan
- Department of Chemical Engineering, Faculty of Engineering, University of Süleyman Demirel, Isparta 32260, Turkey
| | - Aziz Kerim Çelik
- Department of Chemical Engineering, Faculty of Engineering, University of Süleyman Demirel, Isparta 32260, Turkey
| | - Ayça Dalbeyler
- Department of Chemical Engineering, Faculty of Engineering, University of Süleyman Demirel, Isparta 32260, Turkey
| | - Nicholas Fantuzzi
- Department of Civil, Chemical, Environmental, and Materials Engineering, University of Bologna, 40126 Bologna, Italy
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64
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Li C, Cheng H, Luo X, Cheng Z, Zhai X. A High Quality-Factor Optical Modulator with Hybrid Graphene-Dielectric Metasurface Based on the Quasi-Bound States in the Continuum. MICROMACHINES 2022; 13:1945. [PMID: 36363965 PMCID: PMC9693007 DOI: 10.3390/mi13111945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 11/02/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
In this paper, we combine the dielectric metasurface with monolayer graphene to realize a high quality(Q)-factor quasi-BIC-based optical modulator, and the corresponding modulation performances are investigated by using the finite-difference time-domain (FDTD) method, which can be well fitting by the Fano formula based on the temporal couple-mode theory. The results demonstrate that bound states in the continuum (BIC) will turn into the quasi-BIC with high Q-factor by breaking the symmetry of every unit of the metasurface. Meanwhile, the amplitude and bandwidth of transmission based on the quasi-BIC mode can be efficiently adjusted by changing the Fermi energy (EF) of monolayer graphene, and the maximum difference in transmission up to 0.92 is achieved. Moreover, we also discuss the influence of the asymmetry degree to further investigate the modulation effect of graphene on the quasi-BIC mode.
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Affiliation(s)
- Chaolong Li
- School of Science, East China Jiaotong University, Nanchang 330013, China
| | - Hongbo Cheng
- Science and Technology on Aerospace Chemical Power Laboratory, Hubei Institute of Aerospace Chemotechnology, Xiangyang 441003, China
| | - Xin Luo
- School of Science, East China Jiaotong University, Nanchang 330013, China
- Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu 610209, China
| | - Ziqiang Cheng
- School of Science, East China Jiaotong University, Nanchang 330013, China
| | - Xiang Zhai
- Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University, Changsha 410082, China
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65
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Wang X, Lin J, Yan Z, Yi Z, Yu J, Zhang W, Qin F, Wu X, Zhang J, Wu P. Tunable high-sensitivity sensing detector based on Bulk Dirac semimetal. RSC Adv 2022; 12:32583-32591. [PMID: 36425681 PMCID: PMC9661490 DOI: 10.1039/d2ra05402g] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Accepted: 11/03/2022] [Indexed: 07/30/2023] Open
Abstract
This paper proposes a tunable sensing detector based on Bulk Dirac semimetals (BDS). The bottom-middle-top structure of the detector is a metal-dielectric-Dirac semimetal. The designed detector is simulated in the frequency domain by the finite element method (FEM). And the simulation results indicate that the detector achieves three perfect absorption peaks with absorptivity greater than 99.8% in the range of 2.4-5.2 THz. We analyze the cause of the absorption peak by using random phase approximation theory. The device exhibits good angular insensitivity in different incident angle ranges, and the three absorption peaks can reach 90% absorption rate when the incident angle is in the ranges of 0-60°. And when adjusting the Fermi level of BDS in the ranges of 0.1-0.5 eV, our detector can realize the frequency regulation of the ultra-wide range of 3.90-4.56 THz and realize multi-frequency controllable sensing while maintain the absorption efficiency above 96%. The detector has maximum sensitivity S of 238.0 GHz per RIU when the external environment of the refractive index changes from 1.0 to 1.8, and the maximum detection accuracy is 6.5. The device has broad development prospects in the field of space detection and high-sensitivity biosensing detection.
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Affiliation(s)
- Xingyu Wang
- Joint Laboratory for Extreme Conditions Matter Properties, Tianfu Institute of Research and Innovation, Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education, Southwest University of Science and Technology Mianyang 621010 China
- Key Laboratory of Science and Technology on Complex Electromagnetic Environment, China Academy of Engineering Physics Mianyang 621900 China
| | - Jiangchuan Lin
- Key Laboratory of Science and Technology on Complex Electromagnetic Environment, China Academy of Engineering Physics Mianyang 621900 China
| | - Zhiyang Yan
- Key Laboratory of Science and Technology on Complex Electromagnetic Environment, China Academy of Engineering Physics Mianyang 621900 China
| | - Zao Yi
- Joint Laboratory for Extreme Conditions Matter Properties, Tianfu Institute of Research and Innovation, Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education, Southwest University of Science and Technology Mianyang 621010 China
| | - Jiaxin Yu
- Joint Laboratory for Extreme Conditions Matter Properties, Tianfu Institute of Research and Innovation, Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education, Southwest University of Science and Technology Mianyang 621010 China
| | - Wei Zhang
- Joint Laboratory for Extreme Conditions Matter Properties, Tianfu Institute of Research and Innovation, Key Laboratory of Testing Technology for Manufacturing Process in Ministry of Education, Southwest University of Science and Technology Mianyang 621010 China
| | - Feng Qin
- Key Laboratory of Science and Technology on Complex Electromagnetic Environment, China Academy of Engineering Physics Mianyang 621900 China
| | - Xianwen Wu
- School of Chemistry and Chemical Engineering, Jishou University Jishou 416000 China
| | - Jianguo Zhang
- Department of Physics and Electronic Engineering, Jinzhong University Jinzhong 030619 China
| | - Pinghui Wu
- Fujian Provincial Key Laboratory for Advanced Micro-nano Photonics Technology and Devices, Quanzhou Normal University Quanzhou 362000 China
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Maqsood MF, Raza MA, Rehman ZU, Tayyeb A, Makhdoom MA, Ghafoor F, Latif U, Khan MF. Role of Solvent Used in Development of Graphene Oxide Coating on AZ31B Magnesium Alloy: Corrosion Behavior and Biocompatibility Analysis. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12213745. [PMID: 36364520 PMCID: PMC9654966 DOI: 10.3390/nano12213745] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/19/2022] [Accepted: 10/22/2022] [Indexed: 05/27/2023]
Abstract
Clinical applications of bio-absorbable magnesium (Mg) and its alloys can be enhanced by increasing their corrosion resistance, using surface modification and functionality. In this study, we synthesized graphene oxide (GO) through improved Hummers' method and deposited it on biodegradable AZ31B Mg alloy for further characterization. Different suspensions of GO were prepared in various solvents, like deionized water, ethanol, and acetone by ultra-sonication. Electrophoretic deposition (EPD) was used to develop GO coatings on AZ31B Mg using different GO suspensions. Effect of various solvents on corrosion behavior, as well as in vitro biocompatibility, was studied. The optimized EPD parameters were 3 volts and 90 s for coating. Different characterization techniques were used to study GO and prepared coatings. Atomic force microscopy found that the average thickness of GO was ~1 nm. Electrochemical behavior of coatings was studied through electrochemical impedance spectroscopy (EIS) and Tafel analysis in Ringer's lactate solution. Tafel analysis revealed that GO coatings deposited by GO water suspension increased corrosion protection efficiency of AZ31B Mg alloy by ~94%. After 72 h incubation in MC3T3-E1 osteoblast cells extract, in vitro analysis was performed to determine the cell viability and biocompatibility of the GO- coated and bare Mg samples. GO coatings deposited by GO water suspension demonstrated ~2× cell viability, as well as nontoxicity and better biocompatibility compared to the bare and other GO-coated Mg samples.
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Affiliation(s)
- Muhammad Faheem Maqsood
- Institute of Metallurgy & Materials Engineering, Faculty of Chemical & Materials Engineering, University of the Punjab, Lahore 54590, Pakistan
- Faculty of Nanotechnology and Advanced Materials Engineering, Sejong University, Seoul 05006, Korea
- Department of Electrical Engineering, Sejong University, 209- Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea
| | - Mohsin Ali Raza
- Institute of Metallurgy & Materials Engineering, Faculty of Chemical & Materials Engineering, University of the Punjab, Lahore 54590, Pakistan
| | - Zaeem Ur Rehman
- Institute of Metallurgy & Materials Engineering, Faculty of Chemical & Materials Engineering, University of the Punjab, Lahore 54590, Pakistan
| | - Asima Tayyeb
- School of Biological Sciences, Quaid-e-Azam Campus, University of the Punjab, Lahore 54590, Pakistan
| | - Muhammad Atif Makhdoom
- Institute of Metallurgy & Materials Engineering, Faculty of Chemical & Materials Engineering, University of the Punjab, Lahore 54590, Pakistan
| | - Faisal Ghafoor
- Department of Electrical Engineering, Sejong University, 209- Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea
| | - Umar Latif
- Institute of Metallurgy & Materials Engineering, Faculty of Chemical & Materials Engineering, University of the Punjab, Lahore 54590, Pakistan
| | - Muhammad Farooq Khan
- Department of Electrical Engineering, Sejong University, 209- Neungdong-ro, Gwangjin-gu, Seoul 05006, Korea
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Li Q, Bi K, Niu Y, Zhou S, Tan L, Mu J, Han S, Zhang S, Geng W, Mei L, Chou X. Modulation of graphene THz absorption based on HAuCl 4 doping method. OPTICS EXPRESS 2022; 30:40482-40490. [PMID: 36298980 DOI: 10.1364/oe.475103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Graphene is an attractive material for terahertz (THz) absorbers because of its tunable Fermi-Level (EF). It has become a research hotspot to modulate the EF of graphene and THz absorption of graphene. Here, a sandwich-structured single layer graphene (SLG)/ Polyimide (PI)/Au THz absorber was proposed, and top-layer graphene was doped by HAuCl4 solutions. The EF of graphene was shifted by HAuCl4 doping, which was characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and Raman tests. The results showed that the EF is shifted about 0.42 eV under 100 mM HAuCl4 doping, the sheet resistance is reduced from 1065 Ω/sq (undoped) to 375 Ω/sq (100 mM). The corresponding absorbance was increased from 40% to 80% at 0.65 THz and increased from 50% to 90% at 2.0 THz under 100 mM HAuCl4 doping. Detailed studies showed that the absorption came from a sandwich structure that meets the impedance matching requirements and provided a thin resonant cavity to capture the incident THz waves. In addition, not only the absorber can be prepared simply, but its results in experiments and simulations agree as well. The proposed device can be applied to electromagnetic shielding and imaging, and the proposed method can be applied to prepare other graphene-based devices.
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Singh R, Scheinecker D, Ludacka U, Kotakoski J. Corrugations in Free-Standing Graphene. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:3562. [PMID: 36296752 PMCID: PMC9611619 DOI: 10.3390/nano12203562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 10/01/2022] [Accepted: 10/04/2022] [Indexed: 06/16/2023]
Abstract
Although both the tendency of 2D materials to bend out of plane as well as its effect on materials' properties are well known, the factors influencing this phenomenon have not been extensively studied. Graphene, the one-atom-thick membrane of carbon atoms, is both arguably the best known 2D material, as well as the most prone to spontaneous corrugations. Here, we use electron diffraction to systematically study the factors influencing corrugations in graphene, including the size of the free-standing area, the preparation method, the amount of surface contamination, and electron-beam-induced structural disorder. We find that mechanically exfoliated graphene is less corrugated than graphene grown via chemical vapor deposition (corrugation amplitude of (0.83±0.10) Å compared to (1.33±0.20) Å for a free-standing area with a diameter of 1.7μm). Similarly, corrugation amplitude grows by more than a factor of two when the diameter of the free- standing area is increased from 1.7μm to ca. 3.0μm. Electron beam irradiation affects the corrugation in two ways, firstly by removing the hydrocarbon contamination, which decreases corrugation, and secondly by creating increasing amounts of disorder into the material, which again increases corrugation. Overall, our results show that control over the sample during both initial preparation and post-preparation treatment allows for a change in the amount of corrugation in free-standing 2D materials, which may lead to new advances in their use in applications.
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69
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Wang D, Zhu W, Yi Z, Ma G, Gao X, Dai B, Yu Y, Zhou G, Wu P, Liu C. Highly sensitive sensing of a magnetic field and temperature based on two open ring channels SPR-PCF. OPTICS EXPRESS 2022; 30:39055-39067. [PMID: 36258455 DOI: 10.1364/oe.470386] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
A surface plasmon resonance (SPR) sensor comprising photonic crystal fiber (PCF) is designed for magnetic field and temperature dual-parameter sensing. In order to make the SPR detection of magnetic field and temperature effectively, the two open ring channels of the proposed sensor are coated with gold and silver layers and filled with magnetic fluid (MF) and Polydimethylsiloxane (PDMS), respectively. The sensor is analyzed by the finite element method and its mode characteristics, structure parameters and sensing performance are investigated. The analysis reveals when the magnetic field is a range of 40-310 Oe and the temperature is a range of 0-60 °C, the maximum magnetic field sensitivity is 308.3 pm/Oe and temperature sensitivity is 6520 pm/°C. Furthermore, temperature and magnetic field do not crosstalk with each other's SPR peak. Its refractive index sensing performance is also investigated, the maximum sensitivity and FOM of the left channel sensing are 16820 nm/RIU and 1605 RIU-1, that of the right channel sensing are 13320 nm/RIU and 2277 RIU-1. Because of its high sensitivity and special sensing performance, the proposed sensor will have potential application in solving the problems of cross-sensitivity and demodulation due to nonlinear changes in sensitivity of dual-parameter sensing.
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Giasafaki D, Mitzithra C, Belessi V, Filippakopoulou T, Koutsioukis A, Georgakilas V, Charalambopoulou G, Steriotis T. Graphene-Based Composites with Silver Nanowires for Electronic Applications. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12193443. [PMID: 36234570 PMCID: PMC9565487 DOI: 10.3390/nano12193443] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/22/2022] [Accepted: 09/26/2022] [Indexed: 05/27/2023]
Abstract
Graphene/metal nanocomposites have shown a strong potential for use in electronic applications. In particular, the combination of silver nanowires (AgNWs) with graphene derivatives leads to the formation of an efficient conductive network, thus improving the electrical properties of a composite. This work focused on developing highly conductive hydrophilic hybrids of simultaneously functionalized and reduced graphene oxide (f-rGO) and AgNWs in different weight ratios by following two different synthetic routes: (a) the physical mixture of f-rGO and AgNWs, and (b) the in situ reduction of GO in the presence of AgNWs. In addition, the role of AgNWs in improving the electrical properties of graphene derivatives was further examined by mixing AgNWs with a hybrid of few-layered graphene with functionalized multiwalled carbon nanotubes (FLG/MWNT-f-OH). The studied materials showed a remarkable improvement in the overall electrical conductivity due to the synergistic effect of their components, which was proportional to the percentage of Ag and dependent on the procedure of the hybrid formation. One of the f-rGO/AgNWs composites was also selected for the preparation of gravure printing inks that were tested to determine their rheological and printing properties. All of the f-rGO/AgNWs composites were shown to be very promising materials for use as conductive inks for flexible electronics.
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Affiliation(s)
- Dimitra Giasafaki
- National Centre for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Christina Mitzithra
- National Centre for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
| | - Vassiliki Belessi
- Department of Graphic Design and Visual Communication, Graphic Arts Technology Study Direction, University of West Attica, 12243 Egaleo, Greece
- Laboratory of Electronic Devices and Materials, Department of Electrical and Electronic Engineering, University of West Attica, 12244 Egaleo, Greece
| | - Theodora Filippakopoulou
- Department of Graphic Design and Visual Communication, Graphic Arts Technology Study Direction, University of West Attica, 12243 Egaleo, Greece
| | | | | | | | - Theodore Steriotis
- National Centre for Scientific Research “Demokritos”, 15341 Agia Paraskevi, Greece
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