천연흑연 박리를 통한 그래핀 잉크 생산 및 프린팅 = Fabrication of Printed Graphene Pattern Via Exfoliation and Ink Formulation of Natural Graphite

다국어 초록 (Multilingual Abstract)

The remarkable mechanical, electrical, and thermal properties of graphene have recently sparked tremendous interest in various research fields. One of the most promising methods to produce large quantities of graphene dispersion is liquid-phase exfoliation (LPE) which utilizes ultrasonic waves or shear stresses to exfoliate bulk graphite into graphene flakes that are a few layers thick. Graphene dispersion produced via LPE can be transformed into graphene ink to further boost graphene’s applications, but producing high-quality graphene more economically remains a challenge. To overcome this shortcoming, an advanced LPE process should be developed that uses relatively cheap natural graphite as a graphene source. In this study, a flow-LPE process was used to exfoliate natural graphite to produce graphene that was three times cheaper and seven times larger than synthetic graphite. The optimal exfoliation conditions in the flow-LPE process were determined in order to produce high-quality graphene flakes. In addition, the structural and electrical properties of the flakes were characterized. The electrical properties of the exfoliated graphene were investigated by carrying out an ink formulation process to prepare graphene ink suitable for inkjet printing, and fabricating a printed graphene pattern. By utilizing natural graphite, this study offers a potential protocol for graphene production, ink formulation, and printed graphene devices in a more industrial-comparable manner.

국문 초록 (Abstract)

그래핀의 우수한 기계적, 전기적, 열적 성질은 최근 몇 년 동안 여러 연구 분야에서 지대한 관심을 불러일으켰다. 그래핀을 생산하는 대표적인 방법인 습식공정 중 액상박리(liquid-phase exfoliation, LPE)는 초음파 및 높은 전단응력을 이용하여 벌크흑연을 그래핀으로 박리하는 기술이다. 액상박리에 의해 생산된 그래핀 분산액은 그래핀 잉크로 전환되어 그 활용폭을 더 넓힐 수 있는 장점이있지만 고품질의 그래핀을 생산하고 가격경쟁력을 확보해야 한다. 위 조건을 만족하기 위해서 그래핀을 효율적으로 박리할 수있는 공정 확보와 더불어 상대적으로 가격이 저렴한 천연흑연 기반의 그래핀 분산액 및 잉크를 생산해야 한다. 본 연구에서는합성흑연 보다 약 3배 정도 저렴하고 그 크기는7배 이상 큰 천연흑연을 흐름반응기 액상박리 공정을 이용하여 박리를 시도하고공정의 최적화와 박리된 그래핀의 구조적, 전기적 특성을 분석하였다. 천연흑연 기반 그래핀의 전기적 특성을 분석하기 위해잉크 정제화 공정을 거쳐 그래핀 잉크를 생산하고 인쇄 장비를 사용하여 그래핀 패턴을 제작하였다. 본 연구를 통해 보다 경제적인그래핀 분산액 및 잉크를 생산하고 그래핀 인쇄 소자를 개발할 수 있는 방법을 제시할 수 있을 것으로 기대된다.

참고문헌 (Reference)

1 Parvez, K, "Water-based and inkjet printable inks made by electrochemically exfoliated graphene" 149 : 213-221, 2019

2 Choi, C. H, "Visible to infrared plasmonic absorption from silver nanostructures enabled by microreactor-assisted solution deposition" 19 (19): 1265-1272, 2017

3 Chae, H, "Thermoelectric temperature sensors by printingwith a simple office inkjet printer" 4 : 151-155, 2016

4 Jo, G, "The application of graphene as electrodes in electrical and optical devices" 23 (23): 112001-, 2012

5 Htwe, Y. Z. N, "Surfactant-assisted water-based graphene conductive inks for flexible electronic application" 125 : 402-412, 2021

6 Backes, C, "Spectroscopic metrics allow in situ measurement of mean size and thickness of liquid-exfoliated few-layer graphene nanosheets" 8 (8): 4311-4323, 2016

7 Paton, K. R, "Scalable production of large quantities of defect-free few-layer graphene by shear exfoliation in liquids" 13 (13): 624-630, 2014

8 Li, J, "Scalable fabrication and integration of graphene microsupercapacitors through full inkjet printing" 11 (11): 8249-8256, 2017

9 Peña-Bahamonde, J, "Recent advances in graphene-based biosensor technology with applications in life sciences" 16 (16): 1-17, 2018

10 Choi, C. H, "Rapid exfoliation for few-layer enriched black phosphorus dispersion via a superhydrophobic silicon-nanowire-embedded microfluidic process" 22 (22): 699-706, 2020

11 Pei, L, "Rapid and efficient intense pulsed light reduction of graphene oxide inks for flexible printed electronics" 7 (7): 51711-51720, 2017

12 Htwe, Y. Z. N, "Optimization of graphene conductive ink using solvent exchange techniques for flexible electronics applications" 274 : 116719-, 2021

13 Falkovsky, L. A, "Optical properties of graphene" 129 (129): 012004-, 2008

14 Cohen-Tanugi, D, "Mechanical strength of nanoporous graphene as a desalination membrane" 14 (14): 6171-6178, 2014

15 Obraztsov, Alexander N, "Making graphene on a large scale" 4 (4): 212-213, 2009

16 Coleman, J. N, "Liquid-phase exfoliation of nanotubes and graphene" 19 (19): 3680-3695, 2009

17 Coleman, J. N, "Liquid exfoliation of defect-free graphene" 46 (46): 14-22, 2013

18 Coleman, J. N, "Liquid exfoliation of defect-free graphene" 46 (46): 14-22, 2013

19 Shi, P. C, "Large-scale production of high-quality graphene sheets by a non-electrified electrochemical exfoliation method" 3 (3): 507-513, 2018

20 Jun, H. Y, "Integrated graphene study with advanced liquid-phase exfoliation, general inkformulation for diverse printing processes, and high-performing printed energy storage device revealing rheological impact on printed graphene device"

21 Torrisi, F, "Inkjet-printed graphene electronics" 6 (6): 2992-3006, 2012

22 Song, J. W, "Inkjet printing of single-walled carbon nanotubes and electrical characterization of the line pattern" 19 (19): 095702-, 2008

23 Basak, I, "Inkjet printing of PEDOT : PSS based conductive patterns for 3D forming applications" 12 (12): 2915-, 2020

24 Li, J, "Inkjet printing of MoS2" 24 (24): 6524-6531, 2014

25 Jun, H. Y, "Inkjet Printing of Few‐Layer Enriched Black Phosphorus Nanosheets for Electronic Devices" 7 (7): 2100577-, 2021

26 Jun, H. Y, "Ink formulation and printing parameters for inkjet printing of two dimensional materials : a mini review" 11 (11): 3441-, 2021

27 Jang, D, "Influence of fluid physical properties on ink-jet printability" 25 (25): 2629-2635, 2009

28 Hernandez, Y, "High-yield production of graphene by liquid-phase exfoliation of graphite" 3 (3): 563-568, 2008

29 Lotya, M, "High-concentration, surfactant-stabilized graphene dispersions" 4 (4): 3155-3162, 2010

30 Khan, U, "High-concentration solvent exfoliation of graphene" 6 (6): 864-871, 2010

31 Phiri, J, "High-concentration shear-exfoliated colloidal dispersion of surfactant-polymerstabilized few-layer graphene sheets" 52 (52): 8321-8337, 2017

32 Garcia de Abajo, F. J, "Graphene plasmonics : challenges and opportunities" 1 (1): 135-152, 2014

33 Li, X, "Graphene hybridization for energy storage applications" 47 (47): 3189-3216, 2018

34 O’Neill, A, "Graphene dispersion and exfoliation in low boiling point solvents" 115 (115): 5422-5428, 2011

35 Liu, W, "Fast production of high-quality graphene via sequential liquid exfoliation" 7 (7): 27027-27030, 2015

36 Bahadır, E. B, "Applications of graphene in electrochemical sensing and biosensing" 76 : 1-14, 2016

37 Choi, C. H, "Air-water interfacial fluidic sonolysis in superhydrophobic silicon-nanowire-embedded system for fast water treatment" 358 : 1594-1600, 2019

38 Da Costa, T. H, "A paper-based electrochemical sensor using inkjet-printed carbon nanotube electrodes" 4 (4): S3044-, 2015

39 Hu, G, "A general ink formulation of 2D crystals for wafer-scale inkjet printing" 2020