PDMS/GO 복합체 박막의 리튬 금속 표면 개질: 리튬전극의 성장 제어 및 리튬금속전지(LMB) 성능 향상 Surface Modification of Li Metal Electrode with PDMS/GO Composite Thin Film: Controlled Growth of Li Layer and Improved Performance of Lithium Metal Battery (LMB)원문보기
리튬금속전지(LMB)는 매우 큰 이론 용량을 갖지만 단락(short circuit), 수명 감소 등을 야기하는 덴드라이트(dendrite)가 형성되는 큰 문제점을 갖고 있다. 본 연구에서는 poly(dimethylsiloxane) (PDMS)에 graphene oxide (GO) nanosheet를 고르게 분산시킨 PDMS/GO 복합체를 합성하였고 이를 박막 형태로 코팅하여 덴드라이트의 형성을 물리적으로 억제할 수 있는 막의 효과를 이끌어내었다. PDMS의 경우, 그 자체로는 이온 전도체가 아니기 때문에 리튬 이온의 통로를 형성시켜 리튬 이온의 이동을 원활하게 하기 위하여 5wt% 불산(HF)으로 에칭하여 PDMS/GO 박막이 이온전도성을 가질 수 있도록 하였다. 주사전자현미경(scanning electron microscopy, SEM)을 통해 전면 및 단면을 관찰하여 PDMS/GO 박막의 형상을 확인하였다. 그리고 PDMS/GO 박막을 리튬금속전지에 적용하여 실시한 배터리 테스트 결과, 100번째 사이클까지 쿨롱 효율(columbic efficiency)이 평균 87.4%로 유지되었고, 박막이 코팅되지 않은 구리 전극보다 과전압이 감소되었음을 전압 구배(voltage profile)를 통해 확인하였다.
리튬금속전지(LMB)는 매우 큰 이론 용량을 갖지만 단락(short circuit), 수명 감소 등을 야기하는 덴드라이트(dendrite)가 형성되는 큰 문제점을 갖고 있다. 본 연구에서는 poly(dimethylsiloxane) (PDMS)에 graphene oxide (GO) nanosheet를 고르게 분산시킨 PDMS/GO 복합체를 합성하였고 이를 박막 형태로 코팅하여 덴드라이트의 형성을 물리적으로 억제할 수 있는 막의 효과를 이끌어내었다. PDMS의 경우, 그 자체로는 이온 전도체가 아니기 때문에 리튬 이온의 통로를 형성시켜 리튬 이온의 이동을 원활하게 하기 위하여 5wt% 불산(HF)으로 에칭하여 PDMS/GO 박막이 이온전도성을 가질 수 있도록 하였다. 주사전자현미경(scanning electron microscopy, SEM)을 통해 전면 및 단면을 관찰하여 PDMS/GO 박막의 형상을 확인하였다. 그리고 PDMS/GO 박막을 리튬금속전지에 적용하여 실시한 배터리 테스트 결과, 100번째 사이클까지 쿨롱 효율(columbic efficiency)이 평균 87.4%로 유지되었고, 박막이 코팅되지 않은 구리 전극보다 과전압이 감소되었음을 전압 구배(voltage profile)를 통해 확인하였다.
Although Lithium metal battery (LMB) has a very large theoretical capacity, it has a critical problem such as formation of dendrite which causes short circuit and short cycle life of the LMB. In this study, PDMS/GO composite with evenly dispersed graphene oxide (GO) nanosheets in poly (dimethylsilox...
Although Lithium metal battery (LMB) has a very large theoretical capacity, it has a critical problem such as formation of dendrite which causes short circuit and short cycle life of the LMB. In this study, PDMS/GO composite with evenly dispersed graphene oxide (GO) nanosheets in poly (dimethylsiloxane) (PDMS) was synthesized and coated into a thin film, resulting in the effect that can physically suppress the formation of dendrite. However, PDMS has low ion conductivity, so that we attained improved ion conductivity of PDMS/GO thin film by etching technic using 5wt% hydrofluoric acid (HF), to facilitate the movement of lithium (Li) ions by forming the channel of Li ions. The morphology of the PDMS/GO thin film was observed to confirm using SEM. When the PDMS/GO thin film was utilized to lithium metal battery system, the columbic efficiency was maintained at 87.4% on average until the 100th cycles. In addition, voltage profiles indicated reduced overpotential in comparison to the electrode without thin film.
Although Lithium metal battery (LMB) has a very large theoretical capacity, it has a critical problem such as formation of dendrite which causes short circuit and short cycle life of the LMB. In this study, PDMS/GO composite with evenly dispersed graphene oxide (GO) nanosheets in poly (dimethylsiloxane) (PDMS) was synthesized and coated into a thin film, resulting in the effect that can physically suppress the formation of dendrite. However, PDMS has low ion conductivity, so that we attained improved ion conductivity of PDMS/GO thin film by etching technic using 5wt% hydrofluoric acid (HF), to facilitate the movement of lithium (Li) ions by forming the channel of Li ions. The morphology of the PDMS/GO thin film was observed to confirm using SEM. When the PDMS/GO thin film was utilized to lithium metal battery system, the columbic efficiency was maintained at 87.4% on average until the 100th cycles. In addition, voltage profiles indicated reduced overpotential in comparison to the electrode without thin film.
* AI 자동 식별 결과로 적합하지 않은 문장이 있을 수 있으니, 이용에 유의하시기 바랍니다.
제안 방법
In this study, the PDMS/GO composite based on Li metal electrode was designed to improve the performance of Li metal battery by effectively suppressing the growth of Li dendrite. The composite of PDMS/GO film was prepared by mixing exfoliated GO nanosheets and PDMS.
대상 데이터
These were used to synthesize GO nanosheets. PDMS elastomer (Sylgard 184A) and crosslinker (Sylgard 184B) were purchased from Dow corning and used to synthesize poly (dimethylsiloxane). Then, tetrahydrofuran (THF) was purchased from Samchun and used as a solvent for PDMS/GO composite.
, 30 wt%) were purchased from Ducsan. Phosphoric acid (H3PO4, 85 wt%) and Graphite powder were purchased from Daejung. These were used to synthesize GO nanosheets.
Sulfuric acid (H2SO4, 98 wt%), potassium permanganate (KMnO4) and hydrogen peroxide (H2O2, 30 wt%) were purchased from Ducsan. Phosphoric acid (H3PO4, 85 wt%) and Graphite powder were purchased from Daejung.
이론/모형
Graphene oxide (GO) nanosheets were synthesized by modified Hummer’s method.
성능/효과
In conclusion, HF-etched PDMS/GO thin film suppresses the formation of dendrite through high mechanical strength and chemical resistance, and prevents direct contact between highly reactive Li metal and electrolyte, resulting in improved performance of lithium metal battery through solving the low columbic efficiency and short lifespan and increse of overpotential.
참고문헌 (31)
H. Sohn, Q. Xiao, A. Seubsai, Y. Ye, J. Lee, H. Han, S. Park, G. Chen, and Y. Lu, "Thermally robust porous bimetallic ( $Ni_xPt_{1-x}$ ) alloy mesocrystals within carbon framework: High-performance catalysts for oxygen reduction and hydrogenation reactions", ACS Appl. Mater. Interfaces, 11, 21435 (2019).
D. Seok, Y. Jeong, K. Han, D. Y. Yoon, and H. Sohn, "Recent progress of electrochemical energy devices: Metal oxide-carbon nanocomposites as materials for next-generation chemical storage for renewable energy", Sustainability, 11, 3694 (2019).
F. Dai, R. Yi, H. Yang, Y. Zhao, L. Luo, M. L. Gordin, H. Sohn, S. Chen, C. Wang, S. Zhang, and D. Wang, "Minimized volume expansion in hierarchical porous silicon upon lithiation", ACS Appl. Mater. Interfaces, 11, 13257 (2019).
K. B. Hwang, H. Sohn, and S. H. Yoon, "Mesostructured niobium-doped titanium oxide-carbon ( $Nb-TiO_2-C$ ) composite as an anode for high-performance lithium-ion batteries", J. Power Sources, 378, 225 (2018).
H. Sohn, D. H. Kim, R. Yi, D. Tang, S.-E. Lee, Y. S. Jung, and D. Wang, "Semimicro-size agglomerate structured silicon-carbon composite as an anode material for high performance lithium-ion batteries", J. Power Sources, 334, 128 (2016).
H. Sohn, D. Kim, J. Lee, and S. Yoon, "Facile synthesis of mesostructured $TiO_2$ -graphitized carbon ( $TiO_2-gC$ ) composite through the hydrothermal process and its application as the anode of lithium ion batteries", RSC Adv., 6, 39484 (2016).
D. Tang, Q. Huang, R. Yi, F. Dai, M. L. Gordin, S. Hu, S. Chen, Z. Yu, H. Sohn, J. Song, and D. Wang, "Room-temperature synthesis of mesoporous $Sn/SnO_2$ composite as anode for sodium-ion batteries", Euro. J. Inorg. Chem., 2016, 1950 (2016).
H. Sohn, M. L. Gordin, M. Regula, D. H. Kim, Y. S. Jung, J. Song, and D. Wang, "Porous spherical polyacrylonitrile-carbon nanocomposite with high loading of sulfur for lithium-sulfur batteries", J. Power Sources, 302, 70 (2016).
Y. Gao, Z. Yan, J. L. Gray, X. He, D. Wang, T. Chen, Q. Huang, Y. C. Li, H. Wang, S. H. Kim, T. E. Mallouk, and D. Wang, "Polymer-inorganic solid-electrolyte interphase for stable lithium metal batteries under lean electrolyte conditions", Nat. Mater., 18, 384 (2019).
Y. Liu, D. Lin, P. Y. Yuen, K. Liu, J. Xie, R. H. Dauskardt, and Y. Cui, "An artificial solid electrolyte interphase with high Li-ion conductivity, mechanical strength, and flexibility for stable lithium metal anodes", Adv. Mater., 29, 1605531 (2017).
J. A. Seo, J. K. Koh, J. H. Koh, and J. H. Kim, "Preparation and characterization of plasticized Poly(vinyl chloride)-g-Poly(oxyethylene methacrylate) graft copolymer electrolyte membranes", Membr. J., 29, 30 (2019).
Y. Jeong, D. Seok, S. Lee W. H. Shin, and H. Sohn, "Polymer/inorganic nanohybrid membrane on lithium metal electrode: Effective control of surficial growth of lithium layer and its improved electrochemical performance", Membr. J., In Press (2020).
K. Liu, A. Pei, H. R. Lee, B. Kong, N. Liu, D. Lin, Y. Liu, C Liu, P. Hsu, Z. Bao, and Y. Cui, "Lithium metal anodes with an adaptive "solid-liquid" interfacial protective layer", J. Am. Chem. Soc., 139, 4815 (2017).
W. Liu, W. Li, D. Zhuo, G. Zheng, Z. Lu, K. Liu, and Y. Cui, "Core-shell nanoparticle coating as an interfacial layer for dendrite-free lithium metal anodes", ACS Cent. Sci., 3, 135 (2017).
G. Zheng, C. Wang, A. Pei, J. Lopez, F. Shi, Z. Chen, A. D. Sendek, H.-W. Lee, Z. Lu, H. Schneider, M. M. Safont-Sempere, S. Chu, Z. Bao, and Y. Cui, "High-performance lithium metal negative electrode with a soft and flowable polymer coating", ACS Energy Lett., 1, 1247 (2016).
A. A. Assegie, J.-H. Cheng, L.-M. Kuo, W.-N. Su, and B.-J. Hwang, "Polyethylene oxide film coating enhances lithium cycling efficiency of an anode-free lithium-metal battery", Nanoscale, 10, 6125 (2018).
B. Zhu, Y. Jin, X. Hu, Q. Zheng, S. Zhang, Q. Wang, and J. Zhu, "Poly(dimethylsiloxane) thin film as a stable interfacial layer for high performance lithium-metal battery anodes", Adv. Mater., 29, 1603755 (2017).
T. Foroozan, F. A. Soto, V. Yurkiv, S. Sharifi-Asl, R. Deivanayagam, Z. Huang, R. Rojaee, F. Mashayek, P. B. Balbuena, and R. Shahbazian-Yassar, "Synergistic effect of graphene oxide for impeding the dendritic plating of Li", Adv. Funct. Mater., 28, 1705917 (2018).
J. Mohanta, D. K. Padhi, and S. Si, "Li ion conductivity in PEO-graphene oxide nanocomposite polymer electrolytes: A study on effect of the counter anion", J. Appl. Polym. Sci., 135, 46336 (2018).
F. J. Yang, Y. F. Huang, M. Q. Zhang, and W. H. Ruan, "Significant improvement of ionic conductivity of high-graphene oxide-loading ice-templated poly (ionic liquid) nanocomposite electrolytes", Polymer, 153, 438 (2018).
H. Yu, B. Zhang, C. Bulin, R. Li, and R. Xing, "High-efficient synthesis of graphene oxide based on improved hummers method", Sci. Rep., 6, 36143 (2016).
N. I. Kovtyukhova, P. J. Ollivier, B. R. Martin, T. E. Mallouk, S. A. Chizhik, E. V. Buzaneva, and A. D. Gorchinskiy, "Layer-by-layer assembly of ultrathin composite films from micron-sized graphite oxide sheets and polycations", Chem. Mater., 11, 771 (1999).
J. Chen, Y. Li, L. Huang, C. Li, and G. Shi, "High-yield preparation of graphene oxide from small graphite flakes via an improved hummers method with a simple purification process", Carbon, 81, 826 (2015).
D. C. Marcano, D. V. Kosynkin, J. M. Berlin, A. Sinitskii, Z. Sun, A. Slesarev, L. B. Alemany, W. Lu, and J. M. Tour, "Improved synthesis of graphene oxide", ACS Nano, 4, 4806 (2010).
D. Konios, M. M. Stylianakis, E. Stratakis, and E. Kymakis, "Dispersion behaviour of graphene oxide and reduced graphene oxide", J. Colloid Interface Sci., 430, 108 (2014).
H. Ha, J. Park, K. Ha, B. D. Freeman, and C. J. Ellison, "Synthesis and gas permeability of highly elastic poly(dimethylsiloxane)/graphene oxide composite elastomers using telechelic polymers", Polymer, 93, 53 (2016).
※ AI-Helper는 부적절한 답변을 할 수 있습니다.