Second, silver nanowires (AgNWs) were synthesized using a modified polyol with continuous flow method to an industrial-scale production level. Schematic illustration of SWCNT/graphene composite film fabrication by air spray coating of SWCNT solution onto a single layer of graphene grown using a CVD method. Morphology change observation of air spray coated SWCNT networks on a graphene/PET composite with varying temperature on a hot plate.
SWCNT solution was air-sprayed onto a single-layer graphene from a copper foil by changing (a) 1 mL and (b) 4 mL of the solution and transferred to a PET substrate. The composite was cleaved on a copper etching solution. e) Transmission of graphene/PET and SWCNT/graphene/PET composites at visible ranges. f) optoelectric data of SWCNT/graphene/PET composite by varying SWCNT solution. a) Bending study and analysis of single layer graphene/PET and SWCNT/graphene/PET composite material was performed using homemade bend analyzer at various bending radii. Thermal stability evaluation of AuCl3 doped single layer graphene/PET and SWCNT/graphene/PET composites.
AgNWs were continuously synthesized using a continuous flow method for up to 8 h. f) Diameter and length data of AgNWs synthesized continuously using a continuous flow method up to 8 h. Purification of AgNWs using non-solvent precipitation method. a,b) UV-Vis absorption spectrum of AgNW solution.
The Importance and Current Status of Transparent Conducting Electrodes
Flexible Alternatives to Indium Tin Oxide
In other approaches, combining graphene with other conducting materials, such as conducting polymers, metal nanowires, and metal grids, can improve the performance of the CVD-grown graphene while maintaining its high transparency.
Research Goals
Highly Stable Single-Wall Carbon Nanotubes/Transparent Graphene Electrodes Containing Uniform Networks of Carbon Nanotubes.
Highly Stable Single-walled Carbon Nanotube/Graphene Composite Transparent
Coating and Growth Mechanisms
- Coating Methods for Carbon Nanotubes
- Chemical Vapor Deposition Growth of Graphene
- Hybridization of Graphene and Carbon Nanotube
The CVD growth of highly crystalline and large area single-layer graphene on metal films has been widely reported. In contrast, transition metal with low carbon solubility, such as copper37, is an excellent candidate for the growth of uniform and large single-layer graphene films. Since graphene synthesis is generally based on catalytic and chemical reaction, the overall process of graphene is formed on.
The high solubility of carbon in the transition metal can lead to mass diffusion of carbon, resulting in uneven graphene multilayering. However, surface-mediated graphene growth is often observed when a transition metal catalyst with low carbon solubility is used. In typical CVD graphene growth, various defects appear during and after graphene growth.
For example, single-crystalline graphene of large size can be grown by suppressing the seed density or by inducing the alignment of graphene growth orientation with perfect bonding of graphene domains. One-step growth of graphene and carbon nanotubes in CVD was demonstrated by Dong et al.
Experiment
- High Crystalline Graphene Growth
- Spray Coating of Single-walled Carbon Nanotubes and Fabrication of Single-walled
- Gold Chloride Doping of Graphene and Single-walled Carbon Nanotube/Graphene
For multilayer graphene/AgNWs/PI composite fabrication, AgNWs are spin-coated on a multilayer graphene/copper foil. For example, when copper foil was loaded in the center of a quartz tube, full coverage of graphene was observed on the front and back of a copper foil (Figure 4-3b-c). When as-prepared copper foil was placed in the center of a quartz tube, we found complete monolayer graphene growth at the front of a copper foil (Figure 4-4a).
In contrast, when the fabricated copper foil was placed at the bottom of a quartz tube, small multilayer patches of graphene flakes were observed on a single layer of graphene on the face of a copper foil (Figure 4-4b). Interestingly, it was observed that complete single-layer graphene was grown on the face of a copper foil. Contrary to other reports, the multilayer graphene/AgNW/PI composite film fabrication process was performed on the multilayer graphene-grown copper foil.
By repeating such methods up to 4 times, almost all AgNWs on a multilayer graphene/copper sheet were welded. High performance with long-term stability of multilayer graphene/AgNW/PI composite TCEs were fabricated on a copper foil.
Figures of Merits
- Surface Characterization and Crystalline Analysis of a Single Walled Carbon
- Opto-electronic Property of a Single-walled Carbon Nanotube/Graphene Composite
- Mechanical Properties of Graphene and Single-walled Carbon Nanotube/Graphene
Doping of Graphene and Single-walled Carbon Nanotube/Graphene Composite
- Chemical doping of graphene films
- Fabrication of Transparent Conducting Electrode of Embedded Silver Nanowires
Figure of Merits
- Growth Mechanism of Multilayer Graphene on a Copper Foil by Using a CVD
- Embedded Silver Nanowires Structure with Graphene and Polyimide
- Opto-electronic Property of Multilayer Graphene and Multilayer Graphene/Silver
- Mechanical Properties of Silver Nanowires/Polyimide, Multilayer
- Environmental Study of Silver Nanowires/Polyimide, Multilayer
Surprisingly, single-layer dominant graphene was observed for the copper foil placed in the center of the quartz tube; however, multilayer graphene growth was observed when a copper foil was placed on the bottom of a quartz tube (Figure 4-3d,e). It should be noted that multilayer graphene was observed only when the back side of the copper foil was partially grown. When the reaction time was extended to 120 minutes, almost completely covered multilayer graphene on the front side of the copper foil was obtained (Figure 4-4f).
When the welding process is over, transparent polyimide solution is coated on a welded AgNW/multilayer graphene/copper foil for direct transfer. As shown in Figure 4-7, optoelectronic property of CVD grown graphene and multilayer graphene/AgNW/PI composite was analyzed using van der paw methods by hall measurement apparatus. By varying the number of spin-coatings of AgNWs from 1 to 4 times on a multilayer graphene layers,.
Both the transmission and sheet resistance values decreased as the fraction of multilayer graphene in a single graphene layer increased. Here, we have tested the mechanical stability under bending of multilayer graphene, AgNWs and multilayer graphene/AgNW/PI. Multilayer graphene and multilayer graphene/AgNW/PI composite film showed the most stable in bending cycles up to 1000 times.
Unlike the graphene/AgNW/PI multilayer composite film, the resistance of the graphene/PI and AgNW/PI multilayer composite film increased significantly when bending was performed with bending radius < 20 mm. Here, the long-term environmental study was analyzed by testing the resistance change of graphene/AgNW/PI, multilayer/PI and AgNW/PI composite films under ambient, 100 ˚C and desulfurization conditions. The multilayer graphene/PI and the multilayer graphene/AgNW/PI film were shown to be very stable without any apparent change in resistance under ambient conditions for 60 days; however, the AgNW/PI composite film showed large resistance changes with time.
In contrast, the graphene/AgNW/PI multilayer composite film and the graphene/PI multilayer composite film were stable under 100 ˚C for 10 days (Figure 4-9b). However, the graphene/PI multilayer composite film and the graphene/AgNW/PI multilayer composite film remained stable up to 7 hours of processing. Environmental test of multilayer graphene/AgNW/PI at (a) 100 ˚C at room conditions, (b) room temperature at room conditions, and (c) sulfurization by immersing the composite film in ammonium persulfate solution.
Conclusion
Since chemical vapor deposition (CVD) graphene grown with the current technology always exhibits unavoidable defects, the uniform coating of highly conductive single-walled carbon nanotubes (SWCNTs) on a graphene layer was suggested and the improvement of the overall performance was observed. Li, F.; Tang, B.; Xiu, J.; Zhang, S., Hydrophilic modification of multiwalled carbon nanotube for building photonic crystals with improved color visibility and mechanical strength. Low-temperature solution processing of graphene-carbon nanotube hybrid materials for high-performance transparent conductors.
Hsieh, C.-T.; Tzou, D.-Y.; Pan, C.; Chen, W.-Y., Microwave-assisted deposition, scalable coating, and wetting behavior of silver nanowire layers. Lee, E.-J.; Chang, M.-H.; Kim, Y.-S.; Kim, J.-Y., High-pressure polyol synthesis of ultrathin silver nanowires: Electrical and optical properties. Gottesman, R.; Tangy, A.; Oussadon, I.; Zitoun, D., Silver nanowires and nanoparticles from a millifluidic reactor: application to metal-assisted silicon etching.
Chou, K.-S.; Hsu, C.-Y.; Liu, B.-T., Salt-mediated polyol synthesis of silver nanowires in a continuous flow tube reactor. ONE.; Wang, L., High-performance flexible metal oxide/silver nanowire-based transparent conductive films using a scalable lamination-assisted dissolution method. Kou, P.; Yang, L.; Chang, C.; Han, S., Improved Flexible Transparent Conductive Electrodes Based on Silver Nanowire Networks by a Simple Approach for Sunlight Illumination.
Yan, X.; Mom, J.; Xu, H.; Wang, C.; Liu, Y., Fabrication of silver nanowires and metal oxide composite transparent electrodes and their application in UV light-emitting diodes. Ahn, Y.; Jeong, Y.; Lee, Y., Improved thermal oxidation stability of solution-processable silver nanowire transparent electrode by reduced graphene oxide. J.; Wei, J.; Guo, J., Highly stable and stretchable graphene-polymer processed silver nanowire hybrid electrodes for flexible displays.
