奈米碳材石墨烯之製備技術與應用前景 Preparation Techniques and Application Outlook for Graphene of Nano-Carbon Material

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1 奈米碳材石墨烯之製備技術與應用前景 Preparation Techniques and Application Outlook for Graphene of Nano-Carbon Material Outline 3D graphene foams and graphene sponge Carbon nanotbue Graphene hybrid materials Graphene based MEMS Application and outlook of graphene 楊啟榮教授 Conclusion 國立 Department of Mechatronic Engineering National Taiwan Normal University Tel: 三維石墨烯泡沫 (3D Graphene Foams) 石墨烯泡沫由於其天然多孔性具有高表面積, 因此可以被運用於儲能方面, 如超級電容器與電池 其結構具有存儲大量能源的潛力 ( 例如氫 ), 使它具有電化學高電容特性 Nature Communications 6, Article number: 7760 doi: /ncomms8760 使用石墨烯泡沫作出的石墨烯化學傳感器其敏感度約超過目前市面上的傳感器 10 倍以上 可檢測到濃度僅 20ppm 的二氧化氮 除此之外還能夠在室溫下偵測氣體, 而現今許多市面上的傳感器則需要高溫下才能夠正常運作 石墨烯泡沫的多孔性質不僅使它比市售傳感器更加有效率且可重複使用, 經由觸電 (electric shock) 的方式可使已被石墨烯泡沫捕捉的氣體分子離開, 也就是說讓大約 100 毫安的電流通過該泡沫, 粒子會自動從傳感器上剝落下來而清除, 使傳感器可以重複使用 Applicability of 3D-graphene-based electrode materials in numerous devices. U. Patil et al., Nanostructured pseudocapacitive materials decorated 3D graphene foam electrodes for next generation supercapacitors, Nanoscale, 2015, 7,

2 3D CVD graphene from Ni foam Schematic for the fabrication process of 3D graphene foam: (a) selfassembly of 3D graphene by a chemical method; (b) template assisted 3D graphene synthesis by a chemical method; (c) template assisted 3D graphene synthesis by the CVD method. Nanoscale, 2015, 7, Nature Materials 10, (2011) Small 7, No. 22, (2011) 經由化學氣相沉積 (CVD) 加工製成的三維石墨烯泡沫 (3D graphene foams), 具有非常高的表面積, 同時保有二維石墨烯之特性, 其超輕薄 高導電性 卓越的機械強度, 柔韌性與彈性開啟了許多應用領域 石墨烯泡沫的可能應用之一為化學感測器 氣體感測器 使用石墨烯泡沫作出的石墨烯感測器其敏感度約超過目前市面上的感測器 10 倍以上, 可檢測到濃度僅 20 ppm 的二氧化氮 此外, 石墨烯泡沫由於多孔性具有高表面積, 可以被運用於儲能方面, 如超級電容器與鋰電池 Hydrous Ruthenium Oxide Nanoparticles Anchored to Graphene and Carbon Nanotube Hybrid Foam for Supercapacitors Ultra-light, compressible and fire-resistant graphene aerogel as a highly efficient and recyclable absorbent for organic liquids Graphene and CNT hybrid foam (GM) RuO 2 +GM 氣凝膠 碳海綿 Microstructure of RGM electrode. (a) Schematic illustration of the preparation process of RGM nanostructure foam. SEM images of (b c) as-grown GM foam (d) Lightly loaded RGM, and (e) heavily loaded RGM. Scientific Reports 4, Article number: 4452 (2014) doi: /srep04452 Images of the fabrication process of the graphene aerogel, where the GO was reacted with EDA (ethylenediamine) for 24 hours at 80 o C and then freeze-drying. J. Mater. Chem. A, 2014, 2,

3 Snapshots of the decreasing electrical resistance of the aerogel (ρ=6.0 mg cm -3 ) under compression, where the higher compressive strain the stronger the brightness of the lamp in the circuit. Adv. Funct. Mater. 2012, DOI: /adfm (b) The ratio of the electrical resistance of the aerogel as a function of the compressive strain. (c) The reproductivity of the electrical resistance of the aerogel under the compression and release cycles to 30% strain. (d) The reproductivity of the electrical resistance of the aerogel to different compressive strains. J. Mater. Chem. A, 2014, 2, J. Mater. Chem. A, 2014, 2, Multifunctional graphene sheet nanoribbon hybrid aerogels 3D nitrogen-doped graphene aerogel-supported Fe 3 O 4 nanoparticles as efficient eletrocatalysts for the oxygen reduction reaction Illustration of the fabrication process of the GO GNR aerogel. (a) GO sheets and GNRs were mixed together by stirring; the mixture was subjected to freezing and freeze-drying, followed by chemical reduction if necessary. (b) Photos of GNRs, GO suspension and GO-GNR aerogel before and after reduction. J. Mater. Chem. A, 2014, 2, (a) Fabrication process for the 3D Fe 3 O 4 /N doped graphene aerogel catalyst. (b d) SEM images of Fe 3 O 4 /N doped graphene aerogel revealing the 3D macroporous structure and uniform distribution of Fe 3 O 4 nanoparticles in the graphene aerogels. J. Am. Chem. Soc. 2012, 134,

4 Superhydrophobic and superoleophilic properties of graphenebased sponges fabricated using a facile dip coating method Oil Absorbents Based on Melamine/Lignin by a Dip Adsorbing Method The fabrication process of UHS sponges (ultralight, highhydrophobic, and superoleophilic sponges). By dipping melamine sponges (a 1 ) into lignin aqueous solution for absorbing lignin (a 2 ) and pyrolyzing in N 2 atmosphere at 400 C, the UHS sponges (a 3 ) were obtained. ACS Sustainable Chem. Eng. 2015, 3, D. D. Nguyen et al., Energy Environ. Sci., 2012, 5, Loofah sponges as 'green' anode material for microbial fuel cells Carbon nanotbue Graphene Hybrid Materials spotid=33732.php Environ. Sci. Technol. 2013, 47, SEM image of the electroactive biofilm grown on the NCP/LSC anode

5 Graphene joins up with CNTs A seamless three-imensional carbon nanotube graphene hybrid material Researchers at Rice University in the US have made a new, seamless ( 無縫 ), 3D hybrid material from graphene and carbon nanotubes. The material, which has an extremely high surface area of more than 2000 m 2 /g, could be used to fabricate energy storage and nanoelectronic devices with superior properties. Many people have tried to attach nanotubes to a metal electrode and it s never gone very well because they get a little electronic barrier right at the interface, Tour said. By growing graphene on metal (in this case copper) and then growing nanotubes from the graphene, the electrical contact between the nanotubes and the metal electrode is ohmic. That means electrons see no difference, because it s all one seamless material. A seamless graphene/nanotube hybrid created at Rice University may be the best electrode interface material possible for many energy storage and electronics applications. Nature Communications 3, Article number: 1225, doi: /ncomms Open-Ended, N-Doped Carbon Nanotube Graphene Hybrid Nanostructures as High-Performance Catalyst Support Structure illustration of nitrogen-doped carbon nanotube-graphene hybrid nanostructure (NCNT-GHN) with open-ended tips. The graphene layers inside the inner cavity of the CNTs can afford additional anchoring points for metal catalyst nanoparticles in virtue of the open-ended tips of CNTs. Moreover. the graphene layers can serve as additional electron transport pathways inside the CNTs, which is beneficial to the formation of an effective threedimensional conductive network between different NCNT-GHNs. Adv. Funct. Mater. 2011, 21, The synthesis of NCNT-GHNs was achieved by a water-assisted CVD process Adv. Funct. Mater. 2011, 21, A hierarchical ( 分層的 ) N-doped carbon nanotube-graphene hybrid nanostructure (NCNT-GHN), in which the graphene layers are distributed inside the CNT inner cavities, was designed to efficiently support noble metal (e.g., PtRu) nanoparticles. Well-dispersed PtRu nanoparticles with diameters of 2 4 nm were immobilized onto these NCNT-GHN supports by a lowtemperature chemical reduction method without any pretreatment. Compared to conventional CNTs and commercial catalysts. a much better catalytic performance was achieved by a synergistic effect of the hierarchical structure (graphene-cnt hybrid) and electronic modulation (N-doping) during the methanol electrooxidation reaction. Improved single-cell performances with longterm stability are also demonstrated using NCNT-GHN as catalyst support

6 A Three-Dimensional Carbon Nanotube/Graphene Sandwich and Its Application as Electrode in Supercapacitors Co(NO 3 ) 2 6H 2 O (0.2 g) and urea ( 尿素 ) (0.4 g) were used as catalyst solution Illustration of the formation of hybrid materials with CNTs grown in between graphene nanosheets, showing stacked layers of graphene oxide (left), catalyst particles adhered onto layer surface after deposition (middle), and CNTs in between graphene layers after CVD growth (right) (750 o C, H 2, 100 sccm; CO 2, 70 sccm for 30 min). Adv. Mater. 2010, 22, (a c) SEM images and (d) TEM image of CGS (Co catalyst: 16 wt%; carbon source: CO 2 ). Adv. Mater. 2010, 22, Preparation of Tunable 3D Pillared Carbon Nanotube-Graphene Networks for High-Performance Capacitance HOPG H 2 SO 4 :HNO 3 =3:1 at R.T. for 10 min (FePc 的熱解 ) SiO 2 coating needed to ensure uniform growth of VACNTs SEM images of (a) the pristine HOPG and the acid-treated, thermally expanded HOPG (b) without and (c) with SiO 2 coating. (d-f) Typical SEM images of the 3D pillared VACNT-graphene architectures under different magnifications. (g-i) Cross-sectional TEM images of the 3D pillared VACNT_graphene architectures under different magnifications. Chem. Mater. 2011, 23, FeC 32 N 8 H 16 (FePc) contains both the metal catalyst and under Ar/H 2 carbon source required for the nanotube growth (a) Schematic diagram of a 3D pillared VACNT (vertically aligned carbon nanotube)- grapheme nanostructure. (b) Schematic representation of the procedure for the preparation of the 3D pillared VACNT-graphene architectures. Optical images of (c) original HOPG with a thickness of 80 µm and (d) the thermally expanded graphene layers intercalated with VACNTs. Chem. Mater. 2011, 23,

7 Graphene based MEMS (a-c) SEM images of the thermally expanded graphene layers intercalated with VACNTs for different pyrolysis times of 5, 10, and 30 min, respectively, and (d) the VACNT pillar height as a function of the nanotube deposition time. SEM images of the 3D pillared VACNT-graphene: (a-b) without and (c-d) with Ni(OH) 2 coating Chem. Mater. 2011, 23, Graphene MEMS: AFM Probe Performance Improvement Electromechanical Piezoresistive Sensing in Suspended Graphene Membranes (a) The graphene transfer process. A Layer of PMMA or PC is applied to one side of chemical vapor deposited graphene on copper foil. Graphene is then etched from the back side of the copper foil using O 2 plasma. Finally, the copper is etched using FeCl 3. (b) Fabrication sequence of the pressure sensor and the corresponding transfer of graphene onto the substrate. Once the graphene is transferred to the chip, the polymer layer is removed and the graphene is etched (c). After fabrication of the devices, they are packaged and wire bonded (d). Nano Lett. 2013, 13, ACS Nano 2013, 7(5), Tapping mode: Graphene-coated probe shows a 10% loss of resolution Contact mode: Graphene-coated probe has an increased strength to wear and a longer lifetime Graphene membrane acts as a strain gauge independent of crystallographic orientation and allows for aggressive size scalability. When compared with conventional pressure sensors, the sensors have orders of magnitude higher sensitivity per unit area

8 Pressure sensors based on suspended graphene membranes (a) Pressure versus voltage measurements of a device with a cavity (blue squares) and a device without a cavity (red hollow circles). There is a clear dependence in the case of the device with a cavity, where the pressure difference leads to bending and strain in the graphene membrane. This dependence is not observed in the unsuspended device. (b) Average rate of change of the voltage relative to the pressure for the cavity devices compared to the noncavity devices. Error bars show their respective standard deviation. (c) Resistance of the same cavity device (black squares) compared to the pressure (red line). The pressure was held constant at different levels. (d) Comparison of sensitivity. Normalized sensitivity per unit area for the graphene pressure sensors in this paper compared to silicon and carbon nanotube-based sensors. The graphene sensor is roughly 20 to 100s of times more sensitive per unit area than the conventional MEMS sensors showing the potential for aggressive scaling. Nano Lett. 2013, 13, (a) Schematic of an unstrained graphene layer over a cavity. (b) Schematic of a strained graphene membrane. The red arrows indicate the force exerted by a pressure difference between the vacuum chamber and the air inside the cavity. (a) Isometric view of the proposed device structure. (b) Cross sectional view of the proposed device structure. Solid-State Electronics 88 (2013) Resistance versus vacuum chamber pressure indicating electromechanical coupling in the graphene pressure sensor. Solid-State Electronics 88 (2013) Output characteristics (I D V DS ) of a device at different locations. The back gate (here: the silicon substrate) was not connected during the measurement, i.e. left floating. Solid-State Electronics 88 (2013)

9 Fabrication of a graphene field effect transistor array on microchannels for ethanol sensing Applied Surface Science 258 (2012) A schematic of the designed graphene FET. The SU-8 microchannels served as gas flow passages that helped the ethanol vapor come in contact with the sensitive region: the graphene channel. A fabrication flow chart for the 3D graphene FET array. (a) The SU-8 3D interdigital structure configuration was formed on a well-cleaned glass or silicon/sio 2 substrate using negative lithography. (b) The SU-8 interdigital structure substrate was coated with UV photoresist, and the top of the interdigital narrow walls was exposed after positive lithography. (c) Two films, 10 nmthick titanium (Ti) and 100 nm-thick platinum (Pt) films, were sequentially deposited on the wafer by magnetron sputtering deposition. (d) A lift-off process was carried out to form Pt/Ti electrodes on top of the SU-8 narrow walls. (e) The chemically reduced graphene pieces printed on the highly doped silicon/sio 2 substrate was the back gate. (f) The two parts from (e) and (d) were combined together to form 3D graphene FETs The interdigital structure design of the SU-8 narrow walls. (a) The type I structure overlap of 50%, and (b) the type II structure overlap of 100%. The time response of the IDS current to a sequence of different ethanol gas injection times. (a) The sample from the type I structure, and (b) the sample from the type II structure. Applied Surface Science 258 (2012) Fabrication and Operation of Polyimide Bimorph Actuators for a Ciliary Motion System Microscopic bimetallic actuator based on a bilayer of graphene and graphene oxide 注意 On-Off 位置與纖毛結構之運動變化 H. Fujita, J. MEMS, Fabrication of the actuator and characterization of bilayer papers. (a) Bilayer paper was produced via the vacuum filtration of a graphene dispersion and a G-O suspension in sequence. (b) The bilayer paper was fabricated into an actuator using a sharp razor blade. (c) Digital photograph of the graphene side. Scale bar: 2 cm. (d) Digital photograph of the G-O side. Scale bar: 2 cm. Nanoscale, 2013, 5,

10 Actuator length: 17 mm G thickness: 3.61 µm GO thicknesses: Scale bar: 1 cm Power on Power off (e) The surface of the graphene paper. Scale bar: 50 µm. (f) The surface of the G-O paper. Scale bar: 50 µm. (g) The The cross-sectional morphology of the bilayer paper indicates a compact combination. Scale bar: 30 µm. (h) Bilayer papers are flexible. Nanoscale, 2013, 5, The workflow of the artificial cilia. The U-shaped beams can be rowed up to form the cilia, which can be used to move objects precisely. Left: schematic of the artificial cilia; right: the pre-fabricated artificial cilia. Objects can be moved to a distance of up to 9 mm in one cycle. Nanoscale, 2013, 5, Humidity sensing behaviors of graphene oxide-silicon bi-layer flexible structure Sensors and Actuators B 161 (2012) Sensors and Actuators B 161 (2012)

11 Integration of Carbon Nanotubes to carbon microelectromechanical systems (C-MEMS) for On-chip Supercapacitors IEEE Transactions on Nanotechnology, 9(6) 2010, C-MEMS CNT/C-MEMS covered by catalyst particles with different deposition time The optimum deposition time (90 min) (a) 30 min (a) 30 min (b) 60 min (b) 60 min Schematic of electrostatic spray deposition (ESD) experimental setup. The catalyst precursors (50 mg Fe(NO 3 ) 3 dissolved in 50 ml ethanol) were sprayed to the heated substrate by the electrostatic force. (c) 90 min (c) 90 min (a) Spincoating of SU-8 photoresist over carbon substrate. (b) Patterning the photoresist by UV exposure. (c) Developing the SU-8 structures. (d) Pyrolysing ( 熱解 ) the photoresist patterns to convert them to carbon structures. The samples were heated at 300 C for 60 min, then kept at 1000 C for 60 min. The heating rate was 2 C/min and the atmosphere was 5% H 2 in N 2. CV curves of C-MEMS (dashed line) and CNT/C-MEMS composites at scan rate 2 mv s 1 in 1 M Na 2 SO 4. IEEE Transactions on Nanotechnology, 9(6) 2010, FTIR of CNT/C-MEMS composites obtained at optimum deposition time (90 min) before and after oxygen plasma treatment. CV curves of CNT/C-MEMS composites obtained at optimum deposition time (90 min) before and after oxygen plasma treatment at scan rate 2 mv s 1 in 1 M Na 2 SO 4. Galvanostatic charge discharge results of CNT/C-MEMS composites obtained at optimum deposition time (90 min) before and after oxygen plasma treatment at charge discharge current density of 0.25 A/g in 1 M Na 2 SO 4. (a) Chronopotentiograms from the 1st to 10th cycles. (b) Charge discharge cycle stability from the 1st to 1000th cycle. IEEE Transactions on Nanotechnology, 9(6) 2010, IEEE Transactions on Nanotechnology, 9(6) 2010,

12 Graphene-Based Bimorph (graphene and epoxy hybrid cantilever system) Microactuators Nano Lett. 2011, 11, Graphene-on-organic film which is in the form of a dragonfly wing. (a) CVD synthesis of centimeter-scale graphene films on a Ni(300 nm)/sio 2 (300 nm)/si substrate. (b) A 30 nm gold layer was deposited on graphene by thermal evaporation to define the four electrodes. (c) Conventional photolithography and RIE with O 2 plasma were employed to pattern the graphene serpentine microheater. (d, e) Two steps of epoxy photolithography were employed to form the cantilever beam and support body. (f-h) BOE and FeCl 3 were used to remove the nickel and SiO 2 sacrificial layers followed by rinsing in DI water to clean the cantilever. (i) The cantilever was reversed and attached on a glass support for measurement. Nano Lett. 2011, 11, High-perfermance and low-cost ion sensitive sensor array based on self-assembled graphene (a) Structure of ISSA sensing region; (b) schematic of an ISSA: when a testing solution contains one type of ion, only the sensing channel with a matched ionophone trigers a signal. The conductance of the graphene layer is recorded by a data logger directly. Sensors and Actuators A 177 (2012) (a) Image of ISSA on a flexible PET substrate; (b) optical image of ISSA; (c) SEM image of LbL self-assembled graphene layer, showing that the average size of graphene sheets is about 100 nm 100 nm. (a) Cr/Au layers were sputtered on a cleaned PET substrate; (b) electrodes were patterned by photolithography; (c) a window area was fabricated by photolithography, protecting the test pads from the adsorption of graphene or CNT solutions; (d) self-assembly of graphene or CNT; (e) lift off; (f) another layer of PET was bonded with the substrate to confine the sensing regions; (g) ionophores were applied. Sensors and Actuators A 177 (2012)

13 Image of measurement setting up. The ISSA was connected to Agilent data logger, and the signals of the four testing channels were recorded simultaneously. Inset: image of packaged ISSA. Output results when testing solution contains (a) NaCl; (b) KCl; (c) CaCl 2 ; (d) HCl. Sensors and Actuators A 177 (2012) (a) Detection limits compare between graphene and carbon nanotube for different ion testing. The detection limit of graphene ISSA is much better than CNT ISSA. (b) The resistance shifts of graphene, CNT and Pt based ISSA on K + testing, similar to the results of other ions. Sensors and Actuators A 177 (2012) Some important domains of graphene applications based on its unique properties Application and outlook of Graphene M. Willander et al., J. Mater. Chem., 22, 2337,

14 Potential application of Graphene Supercapacitor Li-ion battery Graphene applications Energy storage Electronics and optronics Transparent conductive film RF transistor Laser mode-locking OLED LCD/touch panel Interconnect Spintronics ( 自旋電子學 ) Photosensor 石墨烯片 ( 粉末 ) 由於具有超比表面積與高導電度, 近幾年來以廣泛應用在許多的儲能材料系統, 例如超級電容器 燃料電池 染料敏化太陽能電池與鋰離子電池 B. H. Hong, Korean Graphene Research Activities and Roadmap, Graphene 2012 Composite material Thermal sink Functionalized plastic Flame retardant ( 阻燃 ) Green energy Gas and bio sensor Solar cell Fuel cell hybrid-electrode Water purification DNA sensor ph sensor Toxic gas sensor 蘇清源, Graphene: The applications in optical electronics and thermal management, SumKen 研討會, Applications for graphene 石墨烯於複合材料之應用技術 ( 分散的均勻性很重要 ) The information refers to end user markets graphene companies are targeting their products to, by percentage. This information was accrued from a comprehensive survey of graphene companies. 球王喬克維奇的新球拍取名 HEAD YouTek Graphene Speed Pro, 球拍中段加入全球最輕 最堅固的石墨烯, 重量分散在球拍兩瑞, 能用更少的力量打出更快的球速 VICTOR 羽球拍

15 大尺寸 CVD 石墨烯的開發與應用 石墨烯透明電極的應用產品與其對應之面電阻範圍 製造商 : 藍石 (Bluestone) 科技公司 中天新聞專訪藍石科技 (Taiwan Bluestone Technology) Ref: 黃承鈞 黃淑娟, 石墨烯材料發展與應用趨勢, 工業材料雜誌, 304 (2012) Graphene touchscreen in action! Concept Mobile Phone of Nokia and Samsung 韓國成均館大學 (SKKU) 與三星電子於 2010 年 6 月率先成功展示尺寸達 30 英吋之石墨烯透明導電膜, 以 CVD 法製備石墨烯, 再以捲對捲之方式將其轉印至 PET 膜上, 並搭配硝酸之化學摻雜, 其單層石墨烯之特性可達穿透度 97.4%, 面電阻 ~125 Ω/ ; 並藉由連續四次石墨烯之堆疊, 達到穿透度 ~90%, 面電阻 ~30Ω/, 並首次展示在觸控面板的應用上 Ref: 黃承鈞 黃淑娟, 石墨烯材料發展與應用趨勢, 工業材料雜誌, 304 (2012) Nokia s Morph is a concept that can be worn around the wrist or used like a standard phone. The phone maker believes graphene could make the phone a reality

16 Rational Design of Hybrid Graphene Films for High- Performance Transparent Electrodes Metal grid/graphene hybrid transparent electrode. Flexibility test of the hybrid electrode fabricated on a PET surface. (a) Image of a bent hybrid electrode on the PET substrate. The electrode was bent to a d = 1 cm cylinder. (b) The sheet resistance of the hybrid electrode ( ), as a function of bending cycles, up to 500 bending cycles. (c,d) optical images of the hybrid film structure after 500 bending cycles. ACS Nano, 2011, 5 (8), ACS Nano, 2011, 5 (8), Graphene photonics and optoelectronics Nature photonics, 4 (2010) Graphene as transparent conductor for UV LED current spreading 5.0mA 2.3mA a c, Schematics of inorganic (a), organic (b) and dye-sensitized (c) solar cells. I and I 3 are iodide and triiodide, respectively. The I and I 3 ions transfer electrons to the oxidized dye molecules, thus completing the internal electrochemical circuit between the photoanode and the counter-electrode. d,e, Schematics of an organic LED (d) and a photodetector (e). The cylinder in d represents an applied voltage Graphene-based transparent contact to a GaN-based UV LED is superior to an ITO contact based on cost, transparency, and, heat and current spreading. However, critical issues such as reliability and degradation of graphene films require and are the subject of further investigation. Semiconductor Today, 6, 8,

17 Dye Sensitized Solar Cell (DSSC) with Pt film 染料敏化電池 (Dye-Sensitized Solar Cell,DSSC) 又稱為有機染料太陽能電池, 具有結構簡單 材料成本低及製程簡單的優點, 而且還可以用印刷方式進行大面積的大量生產 染料敏化電池的結構由兩片玻璃基板 兩片 TCO 與電極, 而與其他薄膜太陽能電池最大的不同在於其中間使用液態的電解液 再加入光觸媒與染料, 其中電極材料以 Pt 為主, 電解液則以碘離子 (I 3- /I - ) 為主, 另外以奈米二氧化鈦 (TiO 2 ) 做為光觸媒, 利用染料吸收太陽光, 達成太陽能發電 Dye Sensitized Solar Cell (DSSC) with carbon film Representation of a dye-sensitized TiO 2 solar cell and the processes involved in energy conversion (S represents the dye sensitizer and I - /I 3- is the charge mediator) 6 CO H 2 O -sunlight C 6 H 12 O H 2 O + 6 O 2 J. Braz. Chem. Soc., Vol. 14, No. 6, , MenuSeq=69390&siteId=lamp&menuUIType=top Dye Sensitized Solar Cell (DSSC) with Graphene layer Capacitors: capacitance and voltage range ChemSusChem, 5(2)(2012) Chem. Soc. Rev., 39 (2010) Nanotechnology, 23 (2012) (F/g) 所謂的電化學電容器 (Electrochemical Capacitor) 又稱為超級電容器 (Supercapacitor), 有別於傳統的介電電容器 (Dielectric Capacitor) 元件, 是以電活性材料或多孔性物質來儲存能量的電容器元件 類似於充電電池, 但比傳統的充電電池具有更高的比功率和高比電容, 並且有很高的循環壽命與穩定性, 其比功率可達到每公斤千瓦數量級以上, 迴圈壽命在萬次以上 因此電化學電容器在電動車以及消費性電子具有極其重要的應用前景 若其容量能進一步提高, 則可望取代電池使用 ACS NANO, 4 (2010)

18 Carbon-Based Supercapacitors 電雙層電容器 (Electrical Double-Layer Capacitor; EDLC): 利用高表面積電極材料與電解質溶液之間的庫侖靜電力, 造成電荷分離的現象, 進而形成電雙層來達到儲存電能的目的 事實上, 這種電容器在電極與電解質溶液之間沒有電荷轉移, 因此並沒有法拉第電流產生, 只靠靜電力吸引而造成電荷分離, 來儲存電能 Carbon-Based Supercapacitors 偽電容器 (Pseudocapacitor): 利用電極與電解液間快速可逆的法拉第電荷轉移來儲存電量, 也就是利用電極表面上被覆的電化學活性物種來進行氧化還原 (Redox) 或電吸附 / 脫附 (Electrosorption/Desorption) 的可逆反應 (Reversible Reaction) 由於牽涉到法拉第電荷轉移, 因此電荷的儲存遠大於傳統的介電電容器及電雙層電容器 Electrical double-layer capacitor (EDLC) Charged (left) and discharged (right) states Pseudocapacitor J. Mater. Chem. A, 2, (2014) Possible strategies to improve both energy and power densities for electrochemical capacitors. Nature Materials 7, (2008) The capacitive performance for carbon and pseudocapacitor electrodes Working principle of Li-ion battery (LiCoO 2 ) (LiNiO 2 ) (LiMn 2 O 4 ) (LiFePO 4 ) (Li/Graphite) + Current collector Al Current collector Cu J. Mater. Chem., 2010, 20, 溶劑 :propylene carbonate, ethylene carbonate, dimethyl carbonate, propiolic acid, butyrolactone 溶質 :LiPF 6 LiBF 4 LiClO 4 LiAsF 6 LiCF 3 SO 3 LiBr 電池放電時, 正極發生還原作用, 吸收電子, 進行陰極反應 ; 負極發生氧化作用, 放出電子, 進行陽極反應 充電時, 正負極剛好發生相反的反應 習慣上電池只由外端分正負極, 正極在放電時進行陰極反應, 充電時進行陽極反應 張彥博等人, 工業材料雜誌, 267 期, 61-70, 2009/03-72-

19 Working principle, materials, and electrolytes of Li-ion battery ( 正極材料 ) ( 負極材料 ) Graphene-based Li-ion battery ( 負極 ) ( 正極 ) V 2 O 5 nanowire/graphene composite Energy Environ. Sci., 2011,4, ( 陽極 ) ( 陰極 ) Graphene-wrapped nanosilicon 傳統負極材料仍以類石墨材料為主, 然而, 低理論電容量 (372 mah/g) 成為未來高能量鋰離子電池發展之瓶頸 RSC Adv., 2011, 1, SnO 2 graphene composite Energy Environ. Sci., 2011,4, 中東玩完! 石墨烯電池充電 10 分鐘跑 1000 公里! 翻轉產業石墨烯手機充電 5 秒 OK 重慶 3 月發布全球首批量產石墨烯手機, 展示可彎折的石墨烯觸摸螢幕 ( 右 ) 和首批量產的石墨烯手機 ( 左 ) ( 新華社 ) 2013 年 10 月 31 日, 上海交大發布含有石墨烯的柔性材料可作為一種透明導電材料, 應用在可彎曲 可折疊電子顯示器 ( 新華社 ) 據 世界報 此前消息, 西班牙 Graphenano 公司 ( 一家以工業規模生產石墨烯的公司 ) 同西班牙科爾瓦多大學合作研究出首例石墨烯聚合材料電池, 其儲電量是目前市場最好產品的三倍, 用此電池提供電力的電動車最多能行駛 1000 公里, 而其充電時間不到 8 分鐘 這種石墨烯聚合材料電池的使用壽命較長, 是傳統氫化電池的四倍, 鋰電池的兩倍 且因石墨烯的特性, 此電池的重量僅為傳統電池的一半, 使得裝載該電池的汽車更加輕量化, 進而提高汽車燃油效率 能想像手機不必攜帶行動電源, 只要出門前充電 5 秒, 電量就可以使用長達半個月嗎? 這樣的技術在石墨烯的幫助下未來將可以實現 目前全球已有超過 200 個機構和 1000 多名研究人員從事石墨烯研發, 然而中國在石墨烯研發上, 目前已申請超過 2200 項專利, 占世界的 3 分之

20 华为 Mate 8, 一个赤裸裸的石墨烯电池炒作案例 電子元件熱管理 (Thermal management) 的重要性 高功率電子元件在運作時為了盡快散熱, 通常會加裝金屬散熱片, 因為金屬具有較高的導熱係數, 常用材料包括銅 鋁或鋁的合金, 但是金屬表面的熱輻射係數很低, 在沒有對流傳熱的條件下, 匯集到金屬表面的熱量很難散發出去 因此, 如何提高熱量跨越氣 - 固相界面, 以獲得更高的金屬材料散熱效果, 已成為亟待解決的問題 配備風扇強制冷卻與金屬鰭片之散熱器 高功率 LED 金屬燈杯與金屬鰭片散熱器 常見物體的放射率 ( 係數 ) 參考值 石墨烯於導熱膠材之應用 W/mK Conductive-Materials.htm TIM 資料出處 : 紅外線熱像儀在微小元件機械性質量測與系統整合創新產品開發應用研討會 銅 鋁金屬材料的導熱性極佳, 但是散熱性卻不佳 目前金屬部品的外表處理技術大都不能提高散熱性能, 甚至有些會產生明顯熱阻效應 ( 例如, 電鍍 陽極氧化 真空鍍 ) 通過散熱塗層技術改善金屬表面的熱輻射效率, 已是提高金屬材料散熱性能的重要途徑 熱界面材料 (thermal interface materials, TIM) 主要在填補兩種材料接合或接觸時產生的微孔隙及表面凹凸不平的孔洞, 減少熱傳遞的阻抗, 提高散熱性 /02/16/all-about-tim/

21 Composition of TIM and its filler TIM compositions: 1. Electrically insulating polymer liquid matrixs (0.1~0.2 W/m.K); e.g., epoxies ( 環氧樹脂 ), silicones ( 矽膠 ), urethanes ( 氨基甲酸乙酯 ), and acrylates ( 丙烯酸酯 ) 2. Thermally conductive fillers e.g, Inorganic powders, metal powders, and carbon powders/fibers/flakes. Graphene based silicone thermal greases ( 比表面積太大, 無法增加混摻比例 ) SO: silicone oil NFG RGO GNP 黃振東, 工業材料雜誌, 220 期, 94 年 4 月, Nature Materials 10, (2011) The preparation process for silicone thermal greases by mechanical colloid mill method. W. Yu et al., Physics Letters A, 378 (2014) Thermal conductivity of different thermal greases as a function of loading Increased thermal conductivity of polymer composites Exceptionally high thermal conductivity of thermal grease: Synergistic effects of graphene and alumina 3.11 W/mK silicone oil K K m = K m η 0.5wt% graphene nanoplatelets (GNPs) W/mK A fixed mass ratio of Al2O3 to MgO particles (7:3) silver/ epoxy Synergistic thermal conductivity enhancement of composites with hybrid fillers. Thermal conductivity of PC/ABS composites with different filler loadings. Y. Qi et al., Plastics Research Online, Society of Plastics Engineers (SPE), (2015) /spepro (RGO) Hybrid filler of alumina and graphene in silicone base. Comparison of thermal conductivity and thermal conductivity enhancement (TCE, η) of thermal greases with and without graphene at different filler loading. W. Yu et al., International Journal of Thermal Sciences, 91 (2015)

22 石墨烯於散熱塗料之應用 ( 增強紅外線輻射散熱 ) 在很多需要高效散熱的領域, 由於受空間 尺寸及環境限制, 無法採用加速強制對流的方式將熱量交換出去, 而僅通過熱傳導又不能滿足需求的情況下, 增強紅外線輻射散熱是首選解決方案 薄膜輻射冷卻技術 分子風扇 (Molecular fan, MF) 該石墨烯基之散熱薄膜是一種水性有機 - 無機複合塗料, 主要成份有片狀石墨烯 界面活性劑 分散劑十二烷基磺酸鈉 (SDBS) 聚四氟乙烯 (PTFE) 丙烯酸共聚物乳液 噴塗鋁片 無噴塗鋁鰭片 50 W LED 安裝於散熱器之 IR 影像比較圖 :(a) 無塗覆, (b) 有塗覆 MFgraphene (a) (b) 散熱塗層技術用於提高金屬材料散熱性能 (a) LED 燈泡, (b) 使用噴塗的鋁片可以取代使用鰭片的散熱片 乾式靜電噴塗粉墨 在分子風扇應用於 LED 已獲得幾項優勢 :(1) 崩潰電壓大於 5 kv;(2) 此介電材料已通過 300 十分鐘的測試 ;(3) 有效的溫度冷卻可以使使用壽命從 延長到 小時 ; (4) 50W LED 光強度提高 22.4%, 節能 10.6% Tun-Jen Hsiao et al., Monolayer graphene dispersion and radiative cooling for high power LED, Nanotechnology, 24 (2013) C. T. Lin, Molecular fan, US Patent: US 8,545,933 B2 (2013) Biomedical Applications of Graphene and Graphene Oxide Graphene-based chemical sensors Accounts of Chemical Research, March 12, 2013 DOI: /ar300159f The biosensor consists of a receptor layer, which consists of a biomolecule (e.g., DNA or protein), and a transducer, which is a graphene-based material

23 石墨烯熱能腦瘤治療新曙光 Ultrafast and sensitive room temperature NH 3 gas sensors based on chemically reduced graphene oxide Normalized resistance change ranged from 1 ppb to 50 ppm in NH 3 Log log plot of response variation 石墨烯奈米粒子的表面積大, 可攜帶大量化療藥物, 由靜脈注射到腦瘤動物體內, 在磁場導引下, 可使局部藥物濃度提昇 20 倍, 隨即配合聚焦超音波震盪, 產生熱治療腫瘤 動物實驗已證明可完全壓抑腦瘤生長 成果佳 這套有幫助的輔佐性療法, 使熱治療與化學治療可以協同作用, 在局部區域, 以非侵入式療法治療腦瘤, 降低不良副作用, 大幅提升患者在治療期間的生活品質, 未來很有機會應用於治療其它實質腫瘤, 造福更多癌症病人 (d) Selectivity plot of the sensing device exposed to 5 ppm NH 3 compared with 1000 ppm CO or CO 2, 50 ppm SO 2 and other analytes diluted to 1% of saturated vapor concentrations. 5 ppm NH 3 in four cycles Nanotechnology 25 (2014) (9pp): doi: / /25/2/ Tuning gas-sensing properties of reduced graphene oxide using tin oxide nanocrystals Graphene: The Game Changer? (a) Schematic of the novel gas-sensing platform of an RGO sheet decorated with SnO 2 NCs. (b) Schematic of the sensor testing system. J. Mater. Chem., 2012, 22, (c and d) Gas sensing signals of NO 2 and NH 3 from RGO sensors with and without SnO 2 NCs. The sensing signal is normalized by the measured sensor current in air (base line, Ig/Ia =1). (e) SnO 2 NC RGO sensor response to NO 2 at various concentrations. (f) The sensitivity of the SnO 2 NC RGO sensor vs. NO 2 concentration. ACS Nano, 6(7) (2012)

24 Forget Silicon Valley: Manchester University creates 'Graphene City' Graphene Research Centre (GC) National University of Singapore (NUS) Scientific Advisory A. Geim K. Novoselov N. Peres The National Graphene Institute had been built in Manchester at a cost of 61m 日本 韓國都在此中心設立講座以培養人才 华为宣布与曼彻斯特大学合作开发石墨烯技术 NUS established the GC in 2010, under the leadership of Prof. Antonio H. Castro Neto, with a startup fund from NUS of S$ 40 Million (8 億台幣 ), 1,000 m 2 of laboratory space, and a state-of-the-art clean room facility of 800 m 2. With these top-notch facilities, the GC will be one of the best equipped and advanced graphene research centers in the world

25 Korean National Assembly Forum on Graphene Graphene Research Activities in Korean B. H. Hong, Korean Graphene Research Activities and Roadmap, Graphene 2012 B. H. Hong, Korean Graphene Research Activities and Roadmap, Graphene Future Applications of Graphene in Samsung 1 st generation pilot line of Samsung Techwin B. H. Hong, Korean Graphene Research Activities and Roadmap, Graphene

26 中研院李連忠博士團隊成立二維材料 (2D Material) 網 李連忠博士 (Lain-Jong Li) 中央研究院原子與分子科學研究所 全球第三大鋼鐵製造商韓國浦項鋼鐵公司 (Posco) 已收購 XG Sciences 20% 股權, 成為最大股東並得到石墨烯生產的許可, 計畫與具有 XG Sciences 19% 股權的韓國韓華石油化學株式會社 (Hanhwa Chemical) 共同合作, 於 2012 年建廠進行石墨烯之生產 B. H. Hong, Korean Graphene Research Activities and Roadmap, Graphene 2012 本網站致力於提供最新穎的二維材料科技新知 產業脈動, 以及相關市場資訊, 期盼建立知識共享平台, 增進讀者對於二維材料的了解與認識, 掌握科學趨勢, 預見材料科學新變革 同時, 藉由此知識平台, 協助產 官 學 研間的資訊整合, 推動整體產業的技術交流與合作, 提升我國新穎材料研發與創新之競爭力, 保持國際領先地位, 以及增加投資新契機 Conclusion There s plenty of opportunities for Graphene. Keep on moving, Taiwan! 敬請批評與指教 Thank you for your attention!