• Bulletin of the Korean Chemical Society
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• 제34권4호
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• pp.1237-1239
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• 2013

• Carbon letters
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• 제27권
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• pp.18-25
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• 2018

In this study, graphene oxide(GO) was used as drug carriers to amorphize poorly watersoluble drugs via a co-spray drying process. Two poorly water-soluble drugs, fenofibrate and ibuprofen, were investigated. It was found that the drug molecules could be in the graphene nanosheets in amorphous or nano crystalline forms and thus have a significantly enhanced dissolution rate compared with the counterpart crystalline form. In addition, the dissolution of the amorphous drug enwrapped with the graphene oxide was higher than that of the amorphous drug in activated carbon (AC) even though the AC possessed a larger specific surface area than that of the graphene oxide. The amorphous formulations also remained stable under accelerated storage conditions ($40^{\circ}C$ and 75% relative humidity) for a study period of 14 months. Therefore, graphene oxide could be a potential drug carrier and amorphization agent for poorly water-soluble drugs to enhance their bioavailability.

• 공업화학
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• 제25권6호
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• pp.581-585
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• 2014

Reduced graphene oxide (RGO)를 수용성 고분자인 poly(styrene sulfonate) (PSS)로 wrapping한 수분산성 그래핀 치환체인 G-PSS와 전도성 고분자인 poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate) (PEDOT/PSS)의 복합화에 관하여 연구하였다. G-PSS의 존재 하에서 PEDOT/PSS의 제자리 화학 중합 반응을 수행하여 복합체(GP)를 얻었다. 생성물의 XPS, IR 및 Raman 분석을 통하여 모노머인 EDOT의 중합이 원활하게 진행되어 PEDOT/PSS가 생성됨과 동시에 그래핀과 복합화되었다는 것을 확인할 수 있었다. 또한 GP는 $4.46{\times}10^2S/m$의 전도도를 나타냈으며, 0.5%의 농도까지 물에 분산이 되어 G-PSS보다 전기적 특성 및 수분산성 모두 우수하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.261-262
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• 2023

Nanomaterials are being actively studied in the fields of cement and concrete. However, research on other nanomaterials is insufficient because much of the carbon-based nanomaterials are made up of carbon nanotubes. Therefore, in this study, carbon-based water-soluble graphene oxide was mixed into mortar according to the cement replacement rate to conduct a characteristic evaluation. As a result, as the substitution rate of graphene oxide increased, workability decreased, and there was no effect of enhancing compressive strength. In addition, it was confirmed that the compressive strength decreased due to a large amount of air bubbles when the mixture was mixed for the purpose of improving workability.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.59-59
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• 2010

Graphene has attracted much interest because of its fascinating electronic structure with excellent electron mobility. However, there are some difficulties in making graphene of large and uniform area for real applications. One alternative is graphite oxide. Since graphite oxide is water soluble, it can be sprayed or spin-coating onto any substrates for applications such as Transparent Conducting Film (TCF) and Field Effect Transistor (FET). In this talk, chemical and physical properties of graphite oxide will be discussed. In addition, possible applications made of graphite oxide (GO) will be introduced.

• Bulletin of the Korean Chemical Society
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• 제33권2호
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• pp.449-452
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• 2012

A polyaniline-gold composite was prepared via the polymerization of aniline hydrochloride with or without water-soluble graphite oxide using auric acid as an oxidant. The reaction products were characterized using Xray photoelectron spectroscopy. The thermal stability and embedded crystallinity of the composites were also investigated using thermogravimetric and X-ray diffraction analyses. The electrical properties of the composites were examined using cyclic voltammetric measurements at room temperature and temperature-dependent DC conductivity within 300-500 K. Compared to pure graphene oxide and polyaniline-gold composite, the polyaniline-gold-graphene composite exhibited higher crystallinity and thermal stability, and higher current density response under equivalent conditions.

• Carbon letters
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• 제13권1호
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• pp.29-33
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• 2012

A novel strategy for the simultaneous reduction and functionalization of graphene oxide (G-O) was developed using polyallylamine hydrochloride (PAAH) as a multi-functional agent. The G-O functionalization by PAAH was carried out under basic conditions to catalyze the epoxide ring opening reaction of G-O with abundant amine groups of PAAH. We found that G-O was not only functionalized with PAAH but also reduced under the reaction condition. Moreover, the synthesized PAAH-functionalized G-O sheets were soluble in water and applicable to the synthesis of nanocomposites with gold nanoparticles.

• 폴리머
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• 제38권1호
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• pp.38-42
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• 2014

Poly[(9,9-bis((6'-(N,N,N-trimethylammonium)hexyl)-2,7-fluorene)-alt-(9,9-bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-9-fluorene)) dibromide(WPF-6-oxy-F)]와 graphene oxide(GO)를 혼합하여 WPF-6-oxy-F-GO를 제조한 후 공기 중에서 감마선을 조사하였다. WPF-6-oxy-F-GO 복합재는 유기태양전지(organic solar cells, OSCs)의 정공수송층(hole transporting layer, HTL)으로서 적용하였다. GO와 비교해 보았을 때, 조사된 WPF-6-oxy-F-GO의 면저항(sheet resistance, $R_{sheet}$)은 약 2배 정도 감소하였다. 이는 감마선 조사를 통하여 WPF-6-oxy-F와 GO 사이의 C-N 결합의 형성으로 인한 ${\pi}-{\pi}$ 공유 결합의 영향과 효율적인 packing 때문이다. 결과적으로, 조사된 WPF-6-oxy-F-GO를 정공수송층으로 적용하였을 때 유기태양전지의 효율은 6.10%까지 증가하였다. 수용성 고분자 WPF-6-oxy-F-GO는 정공수송층으로서 사용되고 있는 PEDOT:PSS를 대체하는 대안 소재로서, 높은 효율과 저가의 유기태양전지를 구현할 수 있을 것으로 기대된다.