Hanwha Chemical Research and Development Center

Daejeon, South Korea

Hanwha Chemical Research and Development Center

Daejeon, South Korea
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Song M.Y.,Chonbuk National University | Bang E.Y.,Hanwha Chemical Research and Development Center | Mumm D.R.,University of California at Irvine | Park H.R.,Chonnam National University
Ceramics International | Year: 2012

LiNi 1-yCo yO 2 (y = 0.1, 0.3 and 0.5) were synthesized by solid state reaction method at 750°C and 850°C from LiOH·H 2O, NiO and Co 3O 4 as starting materials. The electrochemical properties of the synthesized LiNi 1-yCo yO 2 were investigated. The synthesized LiNi 1-yCo yO 2 had a α-NaFeO 2 structure with a space group of R3̄m. Among all of the prepared LiNi 1-yCo yO 2 (y = 0.1, 0.3 and 0.5) samples, LiNi 0.7Co 0.3O 2 calcined at 850°C for 40 h had the largest first discharge capacity of 146.2 mAh/g and a relatively low discharge capacity fading rate. © 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.


Bang E.Y.,Hanwha Chemical Research and Development Center | Mumm D.R.,University of California at Irvine | Park H.R.,Chonnam National University | Song M.Y.,Chonbuk National University
Ceramics International | Year: 2012

LiNi 1-yCo yO 2 (y = 0.1, 0.3 and 0.5) are synthesized by a solid-state reaction method at 800°C and 850°C from Li 2CO 3, NiO and Co 3O 4 as starting materials. The electrochemical properties of the synthesized LiNi 1-yCo yO 2 are investigated. The synthesized LiNi 1-yCo yO 2 has an α-NaFeO 2 structure with a rhombohedral system (space group; R3̄m). Among all of the prepared LiNi 1-yCo yO 2 (y = 0.1, 0.3 and 0.5) samples, LiNi 0.5Co 0.5O 2 calcined at 800°C for 40 h has the best cycling performance (capacity fading rate 1.4 mAh/g/cycle) and a relatively large first discharge capacity (147.6 mAh/g). LiNi 0.5Co 0.5O 2 calcined at 800°C for 40 h has a large value of I 0 0 3/I 1 0 4. The low degree of displacement of the nickel and lithium ions in this sample is believed to have led to its relatively large first discharge capacity and best cycling performance. © 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.


Kim J.,University of Notre Dame | Ok Kim D.,Hanwha Chemical Research and Development Center | Wook Kim D.,Hanwha Chemical Research and Development Center | Sagong K.,Hanwha Chemical Research and Development Center
Journal of Solid State Chemistry | Year: 2015

This paper describes the synthetic effort for a Zn-MOF imparting Ti-H as a preferential binding site potentially capturing H2 molecules via Kubas-type interaction. The formation mechanism of Ti-H innate to the final material was potentially demonstrated to follow a radical dissociation rather than a β-hydrogen elimination and a C-H reductive elimination. © 2015 Elsevier Inc. All rights reserved.


Kim J.,Seoul National University | Han J.,Seoul National University | Seo M.,Seoul National University | Kang S.,Seoul National University | And 2 more authors.
Journal of Materials Chemistry A | Year: 2013

A chlorine-assisted method for synthesizing porous boron nitride (BN) is developed. Large scale fabrication is possible by this method under moderate conditions. B and N sources, TiB2 and TiN, respectively, are reacted under a chlorine atmosphere to yield a porous turbostratic BN that displayed a higher surface area (960 m2 g-1) and a larger micropore volume (0.38 cm3 g-1) than have been reported by others. The products exhibit a high hydrogen uptake, as high as 1.01 wt% at 77 K and 1 bar. These results also indicate that the porous BN is a good candidate for testing as a catalyst support and gas sorption material. © The Royal Society of Chemistry 2013.


Seo M.S.,Seoul National University | Kim J.H.,Seoul National University | Kim J.M.,Seoul National University | Han J.S.,Seoul National University | And 3 more authors.
Carbon | Year: 2013

Pore structure of carbide-derived carbon (CDC) was tunable by chlorination of Ti(C1-xAx) solid-solution carbides (A = O or N). High-energy ball milling method was used to synthesize various nanocrystalline Ti(C1-xAx) phases. We were able to obtain specific dimension of pore volumes in the range of micropore (<2 nm) or mesopore size (2-50 nm), depending on the compositions of the precursors. The substitutional atoms and their contents effectively modify the characteristics of pores i.e., pore size, volume and their distributions. The micropore volume density, total pore volume density and specific surface area (SSA) of Ti(C0.7O0.3) CDCs were found 1.55 cm 3/g, 1.72 cm3/g and 3100 m2/g, respectively. In contrast, Ti(C0.5N0.5) CDCs showed enhancement of mesopore formation with 3.34 cm3/g, 3.45 cm3/g and 522 m2/g for mesopore volume density, total pore volume density and SSA, respectively. © 2013 Elsevier Ltd. All rights reserved.


Kim J.,Hanwha Chemical Research and Development Center | Kim D.O.,Hanwha Chemical Research and Development Center | Kim D.W.,Hanwha Chemical Research and Development Center | Park J.,Hanwha Chemical Research and Development Center | Jung M.S.,Hanwha Chemical Research and Development Center
Inorganica Chimica Acta | Year: 2012

The specific yield of postsynthetic modification for modified IRMOF-16 (HCC-1), synthesized using 1,4-di(4-carboxy-2-hydroxyphenyl)benzene as organic ligand and Zn(NO 3) 2·6H 2O as metal source, respectively, has been investigated with the variation of its BET surface area, reaction time and organic-metal precursor. Two kinds of HCC-1 having different values of BET surface area (HCC-1H: 3000 m 2/g and HCC-1L: 2000 m 2/g) were prepared via solvothermal method for the study of effect of BET surface area, whereas isopropoxytitanatrane and tetrabenzyl titanium were adopted as organic-metal precursors It was observed that even if the specific yields of postsynthetic modification for both organic-metal precursors increased with the value of BET surface area of HCC-1, isopropoxytitanatrane showed relatively higher values than those of tetrabenzyl titanium during the entire range of reaction. These observations led us to conclude that HCC-1H has higher specific number of -OH groups, active sites for postsynthetic modification, and tetrabenzyl titanium experiences more difficulty in diffusing deep into HCC-1 due to its relatively larger molecular size. For the effect of reaction time, while it increased slowly with the reaction time until 48 h and then leveled off for HCC-1H, it increased during the entire range of reaction time for HCC-1L. © 2012 Elsevier B.V. All rights reserved.


Kim J.,Hanwha Chemical Research and Development Center | Kim D.O.,Hanwha Chemical Research and Development Center | Kim D.W.,Hanwha Chemical Research and Development Center | Sagong K.,Hanwha Chemical Research and Development Center
Journal of Solid State Chemistry | Year: 2013

To accomplish the postsynthetic modification of MOF with organic-metal precursors (OMPs) described in our previous researches more efficiently, synthesis of MOF (HCC-2) possessing relatively larger pore size as well as higher number of hydroxyl functional side groups per its base unit than those of HCC-1 has been successfully conducted via adopting 1,4-di-(4-carboxy-2,6- dihydroxyphenyl)benzene as an organic ligand and Zn(NO 3) 2·6H 2O as a metal source, respectively. Also, optimization about the Activation process of HCC-2 was performed to maximize its BET (Brunauer-Emmett-Teller) surface area which was proved to be proportional to the number of exposed active sites on which its postsynthetic modification occurred. However, Activation process having been validated to be so effective with the acquirement of highly-purified HCC-1 (CO 2 supercritical drying step followed by vacuum drying step) was less satisfactory with the case of HCC-2. This might be attributed to relatively higher hydrophilicity and bulkier molecular structure of organic ligand of HCC-2. However, it was readily settled by simple modification of above Activation process. Moreover, indispensable residues composed of both DMF and its thermally degraded derivatives which were chemically attached via coordination bond with hydroxyl functionalities even after Activation process III might enable their H 2 adsorption properties to be seriously debased compared to that of IRMOF-16 having no hydroxyl functionalities. © 2012 Elsevier Inc. All rights reserved.


Kim D.O.,Hanwha Chemical Research and Development Center | Park J.,Hanwha Chemical Research and Development Center | Ahn G.R.,Hanwha Chemical Research and Development Center | Jeon H.J.,Hanwha Chemical Research and Development Center | And 5 more authors.
Inorganica Chimica Acta | Year: 2011

For the preparation of MOFs which can be modified via postsynthetic modification, a homologous series of p-terphenyl-4,4′-dicarboxylic acid having hydroxyl side groups, ranging from 0 to 4, as functional groups have been synthesized. Then the modified IRMOF-16, named as HCC-1, has been successfully synthesized via solvothermal and microwave method using 1,4-di(4-carboxy-2- hydroxyphenyl)benzene as organic ligand and Zn(NO3) 2·6H2O as metal source, respectively. A series of structural analyses have identified that it has the same crystal structure and dimensions as those of IRMOF-16. Despite the successful synthesis, conventional method of activation did not proved to be adequate for HCC-1 because of structural collapse. However, this problem could be minimized with the help of continuous CO2 supercritical drying (SCD) process. © 2011 Elsevier Ltd. All rights reserved.


Jang E.R.,Yonsei University | Ryu M.,Ajou University | Park J.E.,Yonsei University | Kim J.-H.,Hanwha Chemical Research and Development Center | And 2 more authors.
Journal of Biological Chemistry | Year: 2010

We screened a protoberberine backbone derivative library for compounds with anti-proliferative effects on p53-defective cancer cells. A compound identified from this small molecule library, cadein1 (cancer-selective death inducer 1), an isoquinolinium derivative, effectively leads to a G2/M delay and caspase-dependent apoptosis in various carcinoma cells with nonfunctional p53. The ability of cadein1 to induce apoptosis in p53-defective colon cancer cells was tightly linked to the presence ofa functionalDNAmismatch repair(MMR)system, which is an important determinant in chemosensitivity. Cadein1 was very effective in MMR+/p53- cells, whereas it was not effective in p53+ cells regardless of theMMRstatus. Consistently, when the function ofMMRwas blocked with short hairpinRNAinSW620 (MMR+/p53 -) cells, cadein1 was no longer effective in inducing apoptosis. Besides, the inhibition of p53 increased the pro-apoptotic effect of cadein1 in HEK293(MMR+/p53+) cells, whereas it did not affect the response to cadein1 in RKO (MMR-/p53+) cells. The apoptotic effects of cadein1 depended on the activation of p38 but not on the activation of Chk2 or other stress-activated kinases in p53-defective cells. Taken together, our results show that cadein1 may have a potential to be an anti-cancer chemotherapeutic agent that is preferentially effective on p53-mutant colon cancer cells with functional MMR. © 2010 by The American Society for Biochemistry and Molecular Biology, Inc.


Gallagher K.G.,Argonne National Laboratory | Kang S.-H.,Argonne National Laboratory | Park S.U.,Hanwha Chemical Research and Development Center | Han S.Y.,Hanwha Chemical Research and Development Center
Journal of Power Sources | Year: 2011

A lithium-ion positive electrode is proposed that contains both high energy density and efficient pulse power capability, even at low state-of-charge (SOC). The pulse power capability at low SOC is attractive for applications, such as plug-in hybrid electric vehicles (PHEVs), which require pulse power operation over the entire useable SOC window. A lithium- and manganese-rich transition-metal layered-oxide (LMR-NMC), also classified as a layered-layered oxide material, is blended with a lithium iron phosphate (LFP) to achieve a potentially low-cost, high-performance electrode. The LMR-NMC material provides high energy by delivering cathode material gravimetric energy densities greater than 890 Wh kg-1. The pulse power capability of this material at low SOC is greatly improved by incorporating a modest quantity of LFP. The LFP serves as an internal redox couple to charge and discharge the more rate-limited LMR-NMC material at moderate to low SOCs. © 2011 Elsevier B.V.

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