Time filter

Source Type

Yoo S.-E.,Chonbuk National University | Seo M.-K.,Korea Institute of Carbon Convergence Technology | Kim B.-S.,Chonbuk National University | Park S.-J.,Inha University
Journal of Industrial and Engineering Chemistry | Year: 2015

In this study, the effect of MoO3 content on the mechanical interfacial properties and the anti-oxidation behaviors of carbon-carbon (C/C) composites were investigated. The MoO3 content was varied to 0, 5, 10, 20, and 30wt% of the resin matrix. These composites were prepared by a one-direction filament winding method, and were subjected to carbonization (heat-treatment at 1100°C). As a result, the anti-oxidation behavior and mechanical interfacial properties improved with increasing MoO3 content at respective heat-treatment temperatures. This is because MoO3 penetrated the composites through the cracks or pores formed during the manufacturing of the C/C composites and preferentially reacted with oxygen, thereby decreasing the rate of oxidation. This disturbed the carbon active species in the composites, increasing the physical cohesion between the interfaces of the carbon fibers and matrices, and improving thermal stability. © 2015 The Korean Society of Industrial and Engineering Chemistry.

Park S.-J.,Inha University | Seo M.-K.,Korea Institute of Carbon Convergence Technology
Springer Series in Materials Science | Year: 2015

Currently, the use of carbon fibers and their composites in space and aerospace applications continues to grow. However, the vast majority of composite molding is used in automotive, marine, industrial, and recreational applications. In this chapter, a brief explanation of various processing methods will be provided and the manufacturing processes typically used to make products found in various applications will be covered. Further, it is classified into two types—open molding and closed molding process—which will be described. © Springer Science+Business Media Dordrecht 2015.

Park S.-J.,Inha University | Kim B.-J.,Korea Institute of Carbon Convergence Technology
Springer Series in Materials Science | Year: 2015

Traditionally, the application of carbon fibers has been limited to very special fields such as aerospace and military because of their high cost. However, various techniques for low-cost carbon fibers are under development in terms of using low-cost precursors, low-cost manufacturing processes, and even functional coating methods. Moreover, future applications of carbon fibers can widen not only as structural reinforcements but also in information technology-based applications such as housings for electric devices, smart cloths, and healthcare items. In this chapter, we will cover the carbon fibers and their composites in recent various applications. In particular, there are classified as a low-cost production technique of carbon fibers for general industries, thin carbon fibers for extreme industries, and functional carbon fibers for smart composites. © Springer Science+Business Media Dordrecht 2015.

Lee H.,Chonbuk National University | Yang S.,Chonbuk National University | Lee J.-H.,Chonbuk National University | Soo Park Y.,Chonbuk National University | Soo Park Y.,Korea Institute of Carbon Convergence Technology
Applied Physics Letters | Year: 2014

We examined the electrooptical properties of a nematic liquid crystal (LC) sample whose substrates were coated with a mixture of carbon nanotube (CNT) and polyimide (PI). The relaxation time of the sample coated with 1.5 wt. % CNT mixture was about 35% reduced compared to the pure polyimide sample. The elastic constant and the order parameter of the CNT-mixture sample were increased and the fast relaxation of LC could be approximated to the mean-field theory. We found the CNT-mixed polyimide formed more smooth surface than the pure PI from atomic force microscopy images, indicating the increased order parameter is related to the smooth surface topology of the CNT-polyimide mixture. © 2014 AIP Publishing LLC.

Chava R.K.,Chonbuk National University | Oh S.-Y.,Chonbuk National University | Oh S.-Y.,Korea Institute of Carbon Convergence Technology | Yu Y.-T.,Chonbuk National University
CrystEngComm | Year: 2016

The interest in hybrid nanoparticles (NPs) arises from their combined and often synergetic properties exceeding the functionality of the individual components. Herein, a general, environmentally friendly, and facile hydrothermal approach to synthesizing the metal-semiconductor, Au@In2O3 core-shell heteronanostructures, is described. These Au@In2O3 core-shell NPs are used as chemiresistive gas sensors for the detection of hydrogen gas in air. The sensor device based on Au@In2O3 core-shell NPs showed ∼4 times greater response and is also more selective to H2 gas compared to the In2O3 NPs sensor device. The enhanced activity can be attributed to the catalytic effect of Au, and synergistic interactions between the Au and In2O3 NPs formed in the core-shell heteronanostructures in such a way that favors the efficient electron transfer at the interface. The hydrogen sensing behavior is dependent on the redox reaction between the H2 and chemisorbed oxygen species. © The Royal Society of Chemistry 2016.

Discover hidden collaborations