关键词：
zinc-bromine battery;high voltage;high energy density;K+-conducting membrane;hybrid electrolytes
摘要：
<jats:title>Abstract</jats:title><jats:p>The zinc‐bromine redox flow battery (ZBB) is an ideal device of energy storage systems. Nevertheless, its energy density is relatively low compared to those of Li‐ion batteries, due to its low output voltage. Herein, a high‐voltage aqueous hybrid zinc‐bromine battery system (AHZBBs) was developed, where K<jats:sup>+</jats:sup>‐conducting membrane was used to segregate neutral‐alkaline hybrid electrolytes and redox couples of Br<jats:sub>2</jats:sub>/Br<jats:sup>−</jats:sup>and [Zn(OH)<jats:sub>4</jats:sub>]<jats:sup>2−</jats:sup>/Zn at the positive and negative electrode. Benefited from an efficient and stable cathode catalyst (carbon‐manganite nanoflakes), this AHZBB delivered a high average output voltage of 2.15 V and energy density of 276.7 Wh/kg without capacity attenuation after 200 cycles. More importantly, this work provides an efficient avenue to elevating the output voltage and energy density, and will strongly encourage studies on redox flow batteries.</jats:p>
通讯作者：
Dr. Junpei Yue<&wdkj&>Prof. Xiongwei Wu<&wdkj&>Prof. Yuping Wu
作者机构：
Institute of Advanced Materials School of Energy Science and Engineering, Nanjing Tech University, Nanjing, 211816 Jiangsu Province, P.R. China;[Jun Mo; Jun Liu; Prof. Canming Liu; Dr. Xianxiang Zeng; Prof. Wenxin Zhou] College of Science, College of Agronomy, Hunan Agricultural University, Changsha, 410128 China;[Jie Huang] Chenzhou Branch Company of Sinopec Hunan Sale Co. LTD, Chenzhou, 423000 P.R. China;[Dr. Junpei Yue] CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190 China;[Dr. Xinhai Yuan; Prof. Yuping Wu] Institute of Advanced Materials School of Energy Science and Engineering, Nanjing Tech University, Nanjing, 211816 Jiangsu Province, P.R. China<&wdkj&>College of Science, College of Agronomy, Hunan Agricultural University, Changsha, 410128 China
通讯机构：
[Dr. Junpei Yue; Prof. Xiongwei Wu] C;[Prof. Yuping Wu] I;CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190 China<&wdkj&>Institute of Advanced Materials School of Energy Science and Engineering, Nanjing Tech University, Nanjing, 211816 Jiangsu Province, P.R. China<&wdkj&>College of Science, College of Agronomy, Hunan Agricultural University, Changsha, 410128 China<&wdkj&>College of Science, College of Agronomy, Hunan Agricultural University, Changsha, 410128 China<&wdkj&>CAS Key Laboratory of Molecular Nanostructure and Nanotechnology, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190 China
关键词：
zinc-bromine battery;high voltage;high energy density;K+-conducting membrane;hybrid electrolytes
摘要：
Water splitting is considered to be a very promising alternative to greenly produce hydrogen, and the key to optimizing this process is the development of suitable electrocatalysts. Here, a sacrificial-counter-electrode method to synthesize a MoS x /carbon nanotubes/Pt catalyst (0.55 wt% Pt loading) is developed, which exhibits a low overpotential of 25 mV at a current density of 10 mA cm(-2), a low Tafel slope of 27 mV dec(-1), and excellent stability under acidic conditions. The theory calculations and experimental results confirm the high hydrogen evolution activity that is likely due to the fact that the S atoms in MoS x can be substituted with O atoms during a potential cycling process when using Pt as a counter-electrode, where the O atoms act as bridges between the catalytic PtO x particles and the MoS x support to generate a MoS x -O-PtO x structure, allowing the Pt atoms to donate more electrons thus facilitating the hydrogen evolution reaction process.
摘要：
用VGCF为模板,用共沉淀方法辅助合成了棒状结构的LiNi1/3Co1/3Mn1/3O2。通过X-射线衍射仪(XRD)、X射线能谱仪(EDX)、扫描电子显微镜(SEM)对其结构进行了表征,并研究了其电化学性能。结果表明:该材料为棒状且表面多孔,并表现出了良好的电化学性能。在0. 2 C(1 C=170 m A/g)的电流密度下,其容量为160 m Ah/g以上,在1 C下经过250个循环后容量仍然有115. 2 m Ah/g,对于制备其他棒状结构的锂离子正极材料提供了一定的借鉴。
作者机构：
[Wu, An-Jun; Ma, Qiang; Wu, Xiong-Wei; Peng, Chang; Deng, Q; Lu, Xiang-Yang; Deng, Qi; Zeng, Xian-Xiang; Zhou, Chun-Jiao] Hunan Agr Univ, Coll Sci, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;[Yin, Ya-Xia; Guo, Yu-Guo] Chinese Acad Sci, Inst Chem, CAS Key Lab Mol Nanostruct & Nanotechnol, CAS Res Educ Ctr Excellence Mol Sci,BNLMS, Beijing 100190, Peoples R China.;[Yin, Ya-Xia; Guo, Yu-Guo] Univ Chinese Acad Sci, Beijing 100049, Peoples R China.
通讯机构：
[Deng, Q; Lu, XY] H;[Guo, Yu-Guo] C;[Guo, Yu-Guo] U;Hunan Agr Univ, Coll Sci, Coll Biosci & Biotechnol, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, Inst Chem, CAS Key Lab Mol Nanostruct & Nanotechnol, CAS Res Educ Ctr Excellence Mol Sci,BNLMS, Beijing 100190, Peoples R China.
关键词：
vanadium redox flow batteries;electrocatalysis;carbon fibers;heteroatoms gradient distribution;long service life
摘要：
The fundamental understanding of electrocatalytic reaction process is anticipated to guide electrode upgradation and acquirement of high-performance vanadium redox flow batteries (VRFBs). Herein, a carbon fiber prototype system with a heteroatom gradient distribution has been developed with enlarged interlayer spacing and a high graphitization that improve the electronic conductivity and accelerate the electrocatalytic reaction, and the mechanism by which gradient-distributed heteroatoms enhance vanadium redox reactions was elucidated with the assistance of density functional theory calculations. All these contributions endow the obtained electrode prominent redox reversibility and durability with only 1.7% decay in energy efficiency over 1000 cycles at 150 mA cm(-2) in the VRFBs. Our work sheds light on the significance of elaborated electrode design and impels the in-depth investigation of VRFBs with long service life.
期刊：
Advanced Energy Materials,2019年9(13):1803854- ISSN：1614-6832
通讯作者：
Wu, Xiong-Wei
作者机构：
[Ma, Qiang; Wu, Xiong-Wei; Deng, Qi; Zeng, Xian-Xiang] Hunan Agr Univ, Coll Agron, Coll Sci, Changsha 410128, Hunan, Peoples R China.;[Ma, Qiang; Zuo, Tong-Tong; Wu, Xiong-Wei; Yue, Junpei; Yin, Ya-Xia; Liang, Jia-Yan] Chinese Acad Sci, CAS Res Educ Ctr Excellence Mol Sci, Inst Chem, CAS Key Lab Mol Nanostruct & Nanotechnol, Beijing 100190, Peoples R China.;[Wu, Xiong-Wei; Deng, Qi] Hunan Prov Yin Feng New Energy Co LTD, Changsha 410000, Hunan, Peoples R China.
通讯机构：
[Wu, Xiong-Wei] H;[Wu, Xiong-Wei] C;Hunan Agr Univ, Coll Agron, Coll Sci, Changsha 410128, Hunan, Peoples R China.;Chinese Acad Sci, CAS Res Educ Ctr Excellence Mol Sci, Inst Chem, CAS Key Lab Mol Nanostruct & Nanotechnol, Beijing 100190, Peoples R China.;Hunan Prov Yin Feng New Energy Co LTD, Changsha 410000, Hunan, Peoples R China.
关键词：
composite polymer electrolytes;dendrite-free;lithium metal batteries;viscoelastic and nonflammable interfaces
摘要：
<jats:title>Abstract</jats:title><jats:p>Herein, a composite polymer electrolyte with a viscoelastic and nonflammable interface is designed to handle the contact issue and preclude Li dendrite formation. The composite polymer electrolyte (cellulose acetate/polyethylene glycol/Li<jats:sub>1.4</jats:sub>Al<jats:sub>0.4</jats:sub>Ti<jats:sub>1.6</jats:sub>P<jats:sub>3</jats:sub>O<jats:sub>12</jats:sub>) exhibits a wide electrochemical window of 5 V (vs Li<jats:sup>+</jats:sup>/Li), a high Li<jats:sup>+</jats:sup> transference number of 0.61, and an excellent ionic conductivity of above 10<jats:sup>−4</jats:sup> S cm<jats:sup>−1</jats:sup> at 60 °C. In particular, the intimate contact, low interfacial impedance, and fast ion‐transport process between the electrodes and solid electrolytes can be simultaneously achieved by the viscoelastic and nonflammable layer. Benefiting from this novel design, solid lithium metal batteries with either LiFePO<jats:sub>4</jats:sub> or LiCoO<jats:sub>2</jats:sub> as cathode exhibit superior cyclability and rate capability, such as a discharge capacity of 157 mA h g<jats:sup>−1</jats:sup> after 100 cycles at C/2 and 97 mA h g<jats:sup>−1</jats:sup> at 5C for LiFePO<jats:sub>4</jats:sub> cathode. Moreover, the smooth and uniform Li surface after long‐term cycling confirms the successful suppression of dendrite formation. The viscoelastic and nonflammable interface modification of solid electrolytes provides a promising and general strategy to handle the interfacial issues and improves the operative safety of solid lithium metal batteries.</jats:p>
关键词：
Cathodes;Ions;Iron compounds;Lithium metallography;Lithium-ion batteries;Microspheres;Scanning electron microscopy;Sodium compounds;Transition metals;Discharge capacities;High capacity;Hollow microsphere;Layered material;Layered Structures;Powder X ray diffraction;Specific capacities;Transition metal layers;Lithium compounds
摘要：
Li-rich layered Li2MnO3 is of great attraction for high energy lithium ion batteries. However, its cycling is still needed for improvements. Here we report a hollow microsphere-structured xLi(2)MnO(3)center dot(1-x)LiNiO2 (x = 0.3-0.7) that is synthesized by using in-situ template-sacrificial strategy. Powder X-ray diffraction (XRD) and scanning electron microscope (SEM) characterizations prove that thexLi(2)MnO(3)center dot(1-x)LiNiO2 (x = 0.3-0.7) are based on monoclinic Li2MnO3 with alpha-NaFeO2 layered structure in which Li+ ions are orderly arranged in the transition metal layers, and the hollow-microspheres have diameters of similar to 3 mu m. Electrochemical results show that the optimal ratio of Li2MnO3/LiNiO(2 )is 0.6/0.4. As a consequence, the stabilized discharge capacity of 0.6Li(2)MnO(3)center dot 0.4LiNiO(2) (0.6LLMNO) is similar to 210 mAh g(-1) after the first few cycles. This shows that appropriate amount Ni substitution for Mn in Li2MnO3 helps to improve the specific capacity and cycling stability. (C) 2019 Elsevier B.V. All rights reserved.
摘要：
A carbon sheet-decorated graphite felt electrode was synthesized by in situ polymerization and subsequent high-temperature calcination under an inert atmosphere. The resultant material brings an improved wettability, numerous defect sites, and abundant O, N and P elements as additional catalytic sites to elevate the reaction kinetics and efficiency of vanadium redox flow batteries (VRF6s). The unique CS modifier enriches electrolyte diffusion pathways, which even show a unique capillary flow. The GF@CS displays a high catalytic activity towards the VO2+/VO2+, V3+/VO2+ and V2+/V3+ oxidation-reduction couples and a reduced cathodic and anodic peak potential difference of 355 mV (vs. 564 mV for GF). The improvement to the electrode results in a GF@CS-based battery presenting an increased capacity of 20.8 Ah L-1 compared to 13.0 Ah L-1 of the GF-based battery and an increase in power density from 225 mA cm(-2) to 300 mA cm(-2). Furthermore, the battery exhibited a 74.79% energy efficiency (EE) at 150 mA cm(-2), with no attenuation even at 300 cycles. GF@CS greatly elevates the reaction kinetics and efficiency of VRFBs. (C) 2019 Elsevier Ltd. All rights reserved.
通讯机构：
[Guo, YG; Wan, LJ] C;[Guo, YG; Wan, LJ] U;Chinese Acad Sci, Key Lab Mol Nanostruct & Nanotechnol, Res Educ Ctr Excellence Mol Sci, BNLMS,Inst Chem, Beijing 100190, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China.
摘要：
The fast-ionic-conducting ceramic electrolyte is promising for next-generation high-energy-density Li-metal batteries, yet its application suffers from the high interfacial resistance and poor interfacial stability. In this study, the compatible solid-state electrolyte was designed by coating Li1.4Al0.4Ti1.6(PO4)(3) (LATP) with polyacrylonitrile (PAN) and polyethylene oxide (PEO) oppositely to satisfy deliberately the disparate interface demands. Wherein, the upper PAN constructs soft-contact with LiNi0.6Mn0.2Co0.2O2, and the lower PEO protects LATP from being reduced, guaranteeing high-voltage tolerance and improved stability toward Li-metal anode performed in one ceramic. Moreover, the core function of LATP is amplified to guide homogeneous ions distribution and hence suppresses the formation of a space-charge layer across interfaces, uncovered by the COMSOL Multiphysics concentration field simulation. Thus, such a bifunctional modified ceramic electrolyte integrates the respective superiority to render Li-metal batteries with excellent cycling stability (89% after 120 cycles), high Coulombic efficiency (exceeding 99.5% per cycle), and a dendrite-free Li anode at 60 degrees C, which represents an overall design of ceramic interface engineering for future practical solid battery systems.
