Cobalt oxide-porous carbon composite derived from CO₂ for the enhanced performance of lithium-ion battery

Choi, Won Yeong,Lee, Dong Kyu,Kim, Hee-Tak,Choi, Jang Wook,Lee, Jae W. Elsevier 2019 Journal of CO₂ utilization Vol.30 No.-

<P><B>Abstract</B></P> <P>As the necessity of eco-friendly energy storage devices grows, lithium-ion batteries (LIBs) have emerged as a promising alternative. While metal oxides, due to their high theoretical capacity, have been investigated as anode materials for LIBs, shortcomings such as poor electrical conductivity and segregation of metal oxide are obstacles in actual practice. To solve these problems, this study synthesized cobalt oxide/porous carbon (Co/CPC) composites through a facile one-step thermal process under gaseous carbon dioxide (CO<SUB>2</SUB>) atmosphere. As-prepared composites showed cobalt oxide nanoparticles well-integrated with the CO<SUB>2</SUB>-derived porous carbon (CPC) and exhibited superior electrochemical performance via a synergistic effect of the cobalt oxide and the CPC. The composites demonstrated a reversible capacity of 1179 mA h·g<SUP>−1</SUP> at a current density of 1000 mA·g<SUP>−1</SUP> and stably retained this capacity over 300 cycles. Therefore, Co/CPC composites prepared from CO<SUB>2</SUB> can be economical and eco-friendly anode materials due to their green synthesis route and outstanding electrochemical performance.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Co<SUB>3</SUB>O<SUB>4</SUB>/Carbon composite was synthesized via one thermal step at 1 atm. </LI> <LI> CO<SUB>2</SUB> was used as both carbon source and oxidizing agent simultaneously. </LI> <LI> Co<SUB>3</SUB>O<SUB>4</SUB> nanoparticles are evenly inserted in the porous carbon layer. </LI> <LI> The composite stably retained 1179 mA h g<SUP>−1</SUP> at 1 A g<SUP>−1</SUP> over 300 cycles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Polarity-tuned Gel Polymer Electrolyte Coating of High-voltage LiCoO₂ Cathode Materials

Park, Jang-Hoon,Cho, Ju-Hyun,Kim, Jong-Su,Shim, Eun-Gi,Lee, Yun-Sung,Lee, Sang-Young The Korean Electrochemical Society 2011 한국전기화학회지 Vol.14 No.2

We demonstrate a new surface modification of high-voltage lithium cobalt oxide ($LiCoO_2$) cathode active materials for lithium-ion batteries. This approach is based on exploitation of a polarity-tuned gel polymer electrolyte (GPE) coating. Herein, two contrast polymers having different polarity are chosen: polyimide (PI) synthesized from thermally curing 4-component (pyromellitic dianhydride/biphenyl dianhydride/phenylenediamine/oxydianiline) polyamic acid (as a polar GPE) and ethylene-vinyl acetate copolymer (EVA) containing 12 wt% vinyl acetate repeating unit (as a less polar GPE). The strong affinity of polyamic acid for $LiCoO_2$ allows the resulting PI coating layer to present a highly-continuous surface film of nanometer thickness. On the other hand, the less polar EVA coating layer is poorly deposited onto the $LiCoO_2$, resulting in a locally agglomerated morphology with relatively high thickness. Based on the characterization of GPE coating layers, their structural difference on the electrochemical performance and thermal stability of high-voltage (herein, 4.4 V) $LiCoO_2$ is thoroughly investigated. In comparison to the EVA coating layer, the PI coating layer is effective in preventing the direct exposure of $LiCoO_2$ to liquid electrolyte, which thus plays a viable role in improving the high-voltage cell performance and mitigating the interfacial exothermic reaction between the charged $LiCoO_2$ and liquid electrolytes.

전기방사 기술을 이용한 리튬 이온배터리 양극용 리튬-니켈-코발트 산화물 나노 구조체 제조 및 전기화학적 특성

서영민,장기훈,안희준,Seo, Yeongmin,Jang, Kihun,Ahn, Heejoon 한국섬유공학회 2016 한국섬유공학회지 Vol.53 No.6

Lithium-ion batteries are products of next-generation energy storage technology that find various applications, e.g., in compact electronic devices and power sources of smart grids, because of their high energy density, low self-discharge, and long life cycles. To be utilized as a power source for a smart grid, lithium-ion batteries require not only a high energy density, but also a high power density. Power density is related to the amount of lithium-ion movement per hour and the surface area of battery electrodes. In this study, an electrospinning technique was used to fabricate a lithium-nickel-cobalt oxide nano-web (LNCOw) with a high specific surface area. The morphology of the LNCOw was investigated by field-emission scanning electron microscopy (FE-SEM), which showed that the LNCOw had an average fiber diameter of 350 nm. Thermogravimetric analysis was performed to determine the optimal temperature for LNCOw synthesis. Furthermore, X-ray diffraction analysis confirmed that the nano-webs consisted of $LiNi_{0.7}Co_{0.3}O_2$. Finally, the specific capacity of LNCOw electrodes was found to be 133.4 mAh/g at 0.2 C-rate, as measured using chronopotentiometry.

Understanding the Critical Role of the Ag Nanophase in Boosting the Initial Reversibility of Transition Metal Oxide Anodes for Lithium-Ion Batteries

Lee, Daehee,Wu, Mihye,Kim, Dong-Hyun,Chae, Changju,Cho, Min Kyung,Kim, Ji-Young,Lee, Sun Sook,Choi, Sungho,Choi, Youngmin,Shin, Tae Joo,Chung, Kyung Yoon,Jeong, Sunho,Moon, Jooho American Chemical Society 2017 ACS APPLIED MATERIALS & INTERFACES Vol.9 No.26

<P>The initial reversible capacity, a critical impediment in transition metal oxide-based anodes, is augmented in conversion-reaction-involved CoO anodes for lithium-ion batteries, by incorporating a chemically synthesized Ag nanophase. With an increase in the added amount of Ag nanophase from 5 to 15 wt %, the initial capacity loss decreases linearly up to 31.7%. The Ag nanophase maintains its pristine metallic nature without undergoing phase transformations, even during repeated vigorous electrochemical reactions of the active CoO phase. Complementary ex situ chemical/physical analyses suggest that the Ag nanophase promotes the catalytic generation of reversible gel-like/polymeric films wherein lithium ions are stored capacitively in the low-voltage region below 0.7 V during discharging. These scientific findings would provide a heretofore unrecognized pathway to resolving a major issue associated with the critical irreversibility in conversion-type transition metal oxide anodes.</P>

Polarity-tuned Gel Polymer Electrolyte Coating of High-voltage LiCoO_2 Cathode Materials

박장훈,이윤성,조주현,김종수,심은지,이상영 한국전기화학회 2011 한국전기화학회지 Vol.14 No.2

We demonstrate a new surface modification of high-voltage lithium cobalt oxide (LiCoO_2) cathode active materials for lithium-ion batteries. This approach is based on exploitation of a polarity-tuned gel polymer electrolyte (GPE) coating. Herein, two contrast polymers having different polarity are chosen: polyimide (PI) synthesized from thermally curing 4-component (pyromellitic dianhydride/biphenyl dianhydride/phenylenediamine/oxydianiline) polyamic acid (as a polar GPE) and ethylene-vinyl acetate copolymer (EVA) containing 12 wt% vinyl acetate repeating unit (as a less polar GPE). The strong affinity of polyamic acid for LiCoO_2 allows the resulting PI coating layer to present a highly-continuous surface film of nanometer thickness. On the other hand, the less polar EVA coating layer is poorly deposited onto the LiCoO_2, resulting in a locally agglomerated morphology with relatively high thickness. Based on the characterization of GPE coating layers, their structural difference on the electrochemical performance and thermal stability of high-voltage (herein, 4.4 V) LiCoO_2 is thoroughly investigated. In comparison to the EVA coating layer, the PI coating layer is effective in preventing the direct exposure of LiCoO_2 to liquid electrolyte, which thus plays a viable role in improving the high-voltage cell performance and mitigating the interfacial exothermic reaction between the charged LiCoO_2 and liquid electrolytes.

The Surface Functionalization of Cobalt Nanoparticles and S8 Adsorption on reduced Graphene Oxide Sheets enhanced by Functional Oxygen Groups for Lithium-Sulfur Batteries

Wook Ahn(안욱),Neema Karima(네마 카리마),Kelvin Jenerali Nyamtara(켈빈 제네랄리) 한국신재생에너지학회 2023 한국신재생에너지학회 학술대회논문집 Vol.2023 No.6

Metal–organic frameworks-derived porous carbon/Co₃O₄ composites for rechargeable lithium–oxygen batteries

Song, Myeong Jun,Kim, Il To,Kim, Young Bok,Kim, Jiwon,Shin, Moo Whan Elsevier 2017 ELECTROCHIMICA ACTA Vol.230 No.-

<P><B>Abstract</B></P> <P>Lithium–oxygen (Li–O<SUB>2</SUB>) batteries are promising candidates for high<B>-</B>performance energy storage systems because of their tremendous energy density, which significantly exceeds that of conventional Li–ion batteries. Cobalt oxide (Co<SUB>3</SUB>O<SUB>4</SUB>) is considered an effective catalyst for non<B>-</B>aqueous Li-O<SUB>2</SUB> batteries owing to its excellent oxygen reduction and oxygen evolution reaction activity. However, low electrical conductivity and agglomeration of Co<SUB>3</SUB>O<SUB>4</SUB> can degrade the electrochemical performance properties. We present a facile method of synthesizing porous carbon/Co<SUB>3</SUB>O<SUB>4</SUB> composites derived from metal–organic frameworks (MOFs) via post-thermal treatment for use as the cathode in rechargeable Li–O<SUB>2</SUB> batteries. Use of cobalt-containing MOFs as a sacrificial template produces uniformly distributed Co<SUB>3</SUB>O<SUB>4</SUB> nanoparticles in the carbonaceous matrix, alleviating the problems of using only Co<SUB>3</SUB>O<SUB>4</SUB> as the cathode material. As-synthesized porous carbon/Co<SUB>3</SUB>O<SUB>4</SUB> composites show superior electrochemical performance, for example, a low overpotential and high reversible capacity of about 9850mAhg<SUP>−1</SUP> at a current density of 100mAg<SUP>−1</SUP>. They also exhibit excellent cyclability up to the 320th cycle, with a limited capacity of 500mAhg<SUP>−1</SUP> at a current density of 200mAg<SUP>−1</SUP>. The improvement is attributed to the catalytic activity and mesoporous structure of uniformly distributed Co<SUB>3</SUB>O<SUB>4</SUB> nanoparticles in the carbonaceous matrix.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We develop porous carbon/Co<SUB>3</SUB>O<SUB>4</SUB> composites for Li–O<SUB>2</SUB> batteries. </LI> <LI> Porous carbon/Co<SUB>3</SUB>O<SUB>4</SUB> composites are derived from cobalt-containing MOFs. </LI> <LI> Co<SUB>3</SUB>O<SUB>4</SUB> nanoparticles catalyze both ORR and OER in a rechargeable Li–O<SUB>2</SUB> system. </LI> <LI> The porous structure of the composites realizes a high discharge capacity. </LI> <LI> The uniform distribution of Co<SUB>3</SUB>O<SUB>4</SUB> realizes effective catalytic effects. </LI> </UL> </P>

Atomic Layer Deposition of Cobalt Oxide Thin Films for Lithium-ion Battery

박재민,임완규,한별,이원준 한국진공학회 2014 한국진공학회 학술발표회초록집 Vol.2014 No.8

A facile preparation of Si-Co/reduced graphene oxide nanocomposite anodes for lithium-ion batteries

박아름,유필진 한국공업화학회 2016 한국공업화학회 연구논문 초록집 Vol.2016 No.0

Although Silicon (Si) has been regarded as one of the most promising due to its high theoretical capacity for Li-ion batteries (LIBs), it suffers from excessive volume expansion (~300%) upon Li insertion, resulting in poor discharge stability and rate capability. In order to improve these performances, Si-Co/reduced graphene oxide (rGO) nanocomposites were prepared by mild ball milling of Si nanoparticles, Cobalt (Co) oxide nanoparticles, and rGO nanosheets, followed by thermal reduction to formation of Si-Co alloy. In particular, Si-Co phase inside the Si domains provides the role of the matrix to alleviate the stress caused by volume change of the Si structure and enhances the electron and ion transport during cycling. Furthermore, rGO nanosheets exhibit the conductive framework, which improves the structural flexibility and electrical conductivity. Therefore, the Si-Co/rGO ternary nanocomposite achieved the high-performance LIBs.

Rational design of metal-organic framework-templated hollow NiCo₂O₄ polyhedrons decorated on macroporous CNT microspheres for improved lithium-ion storage properties

Park, Seung-Keun,Yang, Su Hyun,Kang, Yun Chan Elsevier 2018 Chemical Engineering Journal Vol.349 No.-

<P><B>Abstract</B></P> <P>We report three-dimensional (3D) porous microspheres comprising interconnected carbon nanotubes (CNT) decorated with hollow NiCo<SUB>2</SUB>O<SUB>4</SUB> polyhedrons (H-NCO/CNT) for high-performance lithium-ion batteries (LIBs). The rationally designed composites are successfully fabricated via the combination of spray-pyrolysis and solution-based methods. The macroporous CNT microsphere obtained by spray pyrolysis acts as a substrate for the growth of the zeolitic imidazolate framework-67 (ZIF-67) in ethanol solution. During ion exchange and subsequent oxidation processes, the ZIF-67 polyhedrons were converted into hollow NiCo<SUB>2</SUB>O<SUB>4</SUB> polyhedrons consisting of small crystal domains. Rational design of such composite microspheres offers a highly conductive 3D porous network that simultaneously enables fast ion and electron diffusion deep inside the electrodes during cycling. In addition, the hollow polyhedron interiors can accommodate large volume changes and shorten the transport pathway for the ions and electrons. Owing to these structural advantages, high capacity, long cycle life, and excellent rate capability are achieved from H-NCO/CNT microspheres when applied as LIB anodes; the discharge capacity of H-NCO/CNT microspheres remained at 1673 mA h g<SUP>−1</SUP> after 200 cycles at a current density of 1.0 A g<SUP>−1</SUP>. Even when cycled at a high current density of 20.0 A g<SUP>−1</SUP>, a high capacity of 639 mA h g<SUP>−1</SUP> could be achieved.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CNT microspheres decorated with hollow NiCo<SUB>2</SUB>O<SUB>4</SUB> polyhedrons are facilely synthesized. </LI> <LI> ZIF-67 polyhedrons are converted into hollow NiCo<SUB>2</SUB>O<SUB>4</SUB> polyhedrons. </LI> <LI> Unique structured composite microspheres exhibit excellent lithium-ion storage properties. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Three-dimensional interconnected microspheres comprising CNTs decorated with hollow NiCo<SUB>2</SUB>O<SUB>4</SUB> polyhedrons were successfully synthesized via the combination of spray pyrolysis and solution-based methods. The unique features of composite microspheres such as the hollow interiors of polyhedrons and macroporous CNT backbones are beneficial for improved electrochemical performance when applied as LIB anodes. Thus, the electrode exhibited high capacity, long cycle life, and excellent rate capability as an anode material for LIBs.</P> <P>[DISPLAY OMISSION]</P>