본 연구에서는 구리 이온(Cu2+ ion) 제거를 위한 산화철(Fe3O4)/다공성 탄소 복합체를 합성하였으며, 이를 바탕으로 구리 이온 제거에 대한 특성 평가를 실시하였다. SEM, XRD 분석을 진행하여 수열합성(hydrothermal) 반응을 이용한 산화철/다공성 탄소 복합체의 형태와 구조를 확인하였다. BET 분석을 통해 비표면적과 기공 크기를 확인하였으며, UV-vis 장비를 통해 성능 평가를 실시하여 자성이 있는 Fe3O4와 다공성 탄소와의 시너지효과를 통해 액체 상태에서 존재하는 구리 이온을 제거할 수 있는 가능성을 제시하였다.

본 연구에서는 탄소나노튜브/화이버/폴리머 복합소재 구조에 대한 재료 물성 및 강성 추정을 다룬다. 수정된 Halpin-Tsai 모델을 적용한 멀티 스케일 해석은 탄소나노튜브의 함유량 비율, CNT 두께-길이 비율, 화이버 부피 함유량, 그리고 화이버 보강각도 변화에 따라서 수행되었다. 본 연구에서 제시한 멀티-스케일 접근방법은 기존 모델을 적용하여 얻은 결과와 비교하여 검증하였다. 매개변수 해석을 통하여 CNT의 적절한 함유량은 적층된 CNTFPC 구조의 구조성능의 향상시킬 수 있는 중요한 특성을 규명하였다.

Carbon molecular sieve (CMS) membrane surpasses the upper-bound trade-off and plasticization phenomenon of polymer membrane. Recently, supported CMS membranes have been investigated to provide both high performance and mechanical strength. Herein, we have investigated the supported CMS hollow fiber membranes on low-cost alumina hollow fiber. To prepare the thin and uniform layers, the dip-coating parameters for intermediate and polymeric layers were varied in terms of the withdrawal rate and solution viscosity, respectively. Then, in order to confirm its feasibility in real industry, mixture gas was permeated through prepared CMS membranes. Moreover, the property of long-term stability was characterized in harsh conditions and further modified.

Nickel oxide(NiO) thin films, nanorods, and carbon nanotube(CNT)/NiO core-shell nanorod structures are fabricated by sputtering Nickel at different deposition time on alumina substrates or single wall carbon nanotube templates followed by oxidation treatments at different temperatures, 400 and 700 oC. Structural analyses are carried out by scanning electron microscopy and x-ray diffraction. NiO thinfilm, nanorod and CNT/NiO core-shell nanorod structurals of the gas sensor structures are tested for detection of H2S gas. The NiO structures exhibit the highest response at 200 oC and high selectivity to H2S among other gases of NO, NH3, H2, CO, etc. The nanorod structures have a higher sensing performance than the thin films and carbon nanotube/NiO core-shell structures. The gold catalyst deposited on NiO nanorods further improve the sensing performance, particularly the recovery kinetics.

본 연구에서는 해수를 유도용액으로 사용하고 하수처리수를 공급수로 사용하는 정삼투막 공정의 유기/바이오 오염물에 의한 막오염을 저감하기 위해 폴리도파민/탄소 나노 튜브 복합 분리막을 제작하였다. 분리막은 기존 계면중합반응에 탄소 나노 튜브를 첨가하여 초박형 복합 분리막을 제조한 후, 폴리도파민으로 코팅시켜 제조하였다. 제작 된 분리막은 알긴산나트륨(Sodium alginate)용액과 미생물(Pseudomonas aeruginosa PA01) 부착 실험을 통하여 수투과도와 막오염도를 평가하였다. 그 결과, 폴리도파민/탄소 나노 튜브 복합 분리막은 복합되지 않은 분리막에 비하여 높은 수투과도와 낮은 막오염 성능을 보였다.

We carried out a dynamic instability assessment of carbon nanotube reinforced composite (CNTRC) and carbon nanotubes/fiber/polymer composite (CNTFPC) skew plates based on the high-order shear deformation plate theory (HSDT). The multiscale interactions between carbon nanotube (CNT) ratios and skew angles on the dynamic instability for various length-thickness ratios are studied using a two-dimensional finite element model developed for this study. The results were verified by those reported in the literature show the interactions between the CNT reinforcement and skew angles in the skew laminate. Numerical examples show the importance of CNT reinforcement when assessing the dynamic instability of CNTRC and CNTFPC skew plates.

Multiwall carbon nanotubes (MWCNT) with two different (L/D) aspect ratios (7±2 μm/140±30 nm and 0.5–2 μm/8–15 nm) were surface treated using nitric acid (HNO3) and polyethyleneimine (PEI) prior to their deposition on carbon fibers (CF). Before the hierarchical reinforcement with CF-MWCNT, the CFs were treated with 3-glycidoxypropyltrimethoxysilane, a coupling agent (Z6040) and with poly(amidoamine) (PAMAM) a dendrimer containing an ethylenediamine core and amine surface groups. The MWCNT were deposited on the CF using two methods, by electrostatic attraction and by chemical reactions. The changes in the CF surface morphology after the MWCNT deposition were analyzed using SEM, which revealed a higher density and uniform coverage for the PAMAM-treated CF and the short MWCNTs. The interfacial adhesion of the composite materials was evaluated using the single fiber fragmentation technique. The results indicated an improvement in the interfacial shear strength with the addition of the short-MWCNTs treated with acid solutions and grafted onto the surface of the CF fiber using electrostatic attraction.

증류에 의한 올레핀/파라핀 분리는 끓는점이 유사하여 에너지 소모가 높기 때문에, 분리막을 이용한 연구가 많이 진행 중이다. 특히 CMS 분리막은 sieving separation에 의한 투과/분리 성능이 우수하다. 따라서 본 연구에서는 중공사형 α-alumina 지지체에 γ-alumina 중간층을 형성한 후 Matrimid로 코팅하여 열분해함으로써 높은 기계적 강도와 충진 밀도를 갖는 중공사형 CMS 복합막을 제조하였다. 제조된 CMS 분리막은 20 - 35 GPU 프로필렌 투과도와 10 이상의 프로필렌/프로판 분리도를 보였다. 이 연구는 2014년 정부(미래창조과학부)의 재원으로 국가과학 기술연구회 융합연구단 사업(No. CRC-14-01-KRICT)의 지원을 받아 수행된 연구입니다.

The aim of the work was to investigate the thermo-electrical properties of low cost and rapidly produced randomly oriented carbon/carbon (C/C) composite. The composite body was fabricated by combining the high-pressure hot-pressing (HP) method with the lowpressure impregnation thermosetting carbonization (ITC) method. After the ITC method step selected samples were graphitized at 3000°C. Detailed characterization of the samples’ physical properties and thermal properties, including thermal diffusivity, thermal conductivity, specific heat and coefficient of thermal expansion, was carried out. Additionally, direct current (DC) electrical conductivity in both the in-plane and through-plane directions was evaluated. The results indicated that after graphitization the specimens had excellent carbon purity (99.9 %) as compared to that after carbonization (98.1). The results further showed an increasing trend in thermal conductivity with temperature for the carbonized samples and a decreasing trend in thermal conductivity with temperature for graphitized samples. The influence of the thickness of the test specimen on the thermal conductivity was found to be negligible. Further, all of the specimens after graphitization displayed an enormous increase in electrical conductivity (from 190 to 565 and 595 to 1180 S/cm in the through-plane and in-plane directions, respectively).

Heavy metals are typical contaminant in water and need to be removed because they are non-biodegradable and can accumulate in human body. To remove metal and other contaminants from water, chemical absorbents are widely used due to their low cost. Herein, hybrid materials comprised of amylose and single wall carbon-nanotube (swCNT) was developed as the absorbent for water purification. A high adsorption properties of carbon-nanotubes have been utilized in designing effective absorbent but its poor dispersity in water is a limiting factor for practical use. Single wall carbon-nanotube was hybridized with amylose chain produced by enzyme reaction of amylosucrase and their tendency to self-assemble in aqueous environment. The amylose-swCNT microparticles were characterized by FE-SEM and turned out to be spherical structure with CNTs embedded throughout the amylose matrix. The ability of amylose-CNT microparticles to remove copper was examined. Concentration of copper was decreased after reaction with amylose-swCNT microparticles. Although amount of decreasing copper was less than swCNT on same total mass, Adsorption efficiency of amylose-swCNT microparticles was good because their swCNT content was only 10% of total mass.

Isroaniso matrix precursor synthesized from commercially available petroleum pitch was stabilized in air. The influence of oxygen mass gain during stabilization on the yield of matrix precursor was studied. Additionally, the influence of pressure on the yield of the stabilized matrix precursor in a real system was studied. The fourier transform infrared spectrometry (FTIR), thermogravimetric analysis (TGA), yield, yield rate, and yield impact were used to check the effect of stabilization and pressure on the yield of the matrix precursor and the end properties of the composite thereafter. The results showed that the yield increased with stabilization duration up to 20 h whereas it decreased for stabilization duration beyond 20 h. Further results showed that the stabilized matrix precursor for a duration of 5 h could withstand almost two-fold greater hot-pressing pressure without resulting in exudation as compared to that of a 1 h stabilized matrix precursor. The enhanced hot-pressing pressure significantly improved the yield of the matrix precursor. As a consequence, the densification and mechanical properties were increased significantly. Further, the matrix precursor stabilized for a duration of 20 h or more failed to provide proper and uniform binding of the reinforcement.

본 연구에서는 유연성을 갖는 전극 제조를 위해 환원된 그래핀 옥사이드/단일벽 탄소나노튜 브 복합체를 금이 코팅된 PET 기판 위에 스프레이 코팅하였다. 제조된 플렉시블한 전극의 전기 용량 값 은 1 M의 황산 전해질과 100 mV s-1 의 주사속도에서 82 F g-1 으로 측정 되었으며, 이 용량 값은 500 번의 굽힘 시험 후에 38 F g-1 로 감소되는 현상을 확인 하였다. 또한, 이러한 결과는 정전류 충 방전과 전기화학 임피던스법을 포함한 전기화학적 분석 결과와도 부합하는 결과를 나타내었다. 유연성을 갖는 환원된 그래핀 옥사이드/단일벽 탄소나노튜브 복합체 전극은 500회의 반복적인 굽힘 시험 후에도 대략 50%의 초기 전기 용량 값을 유지 할 수 있었으며, 이러한 여러 가지 전기화학적 특성을 고려하여 볼 때 미래 개발 가능한 플렉시블한 에너지 저장 매체로써의 적용이 가능 하다는 점을 확인 할 수 있었 다.