Biography:

Zhang Qiang, Professor of Tsinghua University, has won National Outstanding Youth Science Fund, National Outstanding Youth Science Fund, Young Talents of the Ten Thousand Talents Program of the Central Organization Department, Newton Advanced Fellowship of the Royal Society of England , 2017 Crowwell Safety Ball Highly Cited Scientist . He is the editor of the international journal J Energy Chem, the editor of Adv Mater Interfaces , Sci China Mater , Sci China Chem , Philos Trans A , and the guest editor of Energy Storage Mater and Adv Funct Mater . Acting as a special reviewer or arbitrator of journals such as Nature Energy , Nature Nanotech , Nature Catal , Sci Adv , JACS , Adv Mater , Angew Chem and other journals. He presided over the national key R & D projects, the National Natural Science Foundation of China, the Doctoral Fund of the Ministry of Education, and the key projects of the Beijing Science and Technology Commission. As first author / corresponding author. Adv Mater, J. Am Chem Soc , Angew Chem Int Ed, Nature Commun, Sci Adv, Chem........... And other published SCI indexed papers 100 over papers; citations issued 17,000 more than once, The h- factor is 76 .

research content:

With the concept of sustainable development and green chemistry, the development of atomic reorganization, molecular assembly, macroscopic flow and process amplification in the transformation of materials

1) Exploring new principles of catalysis at the nanoscale and using nanomaterials to develop efficient chemical processes

2) Development of advanced functional materials synthesis methodology for new micro / nano composite structures

3) Develop nano-reactor technology and develop new processes for efficient and advanced materials and energy conversion.

4) Develop carbon-based composite materials for energy storage, and explore its macro preparation technology.

Classic achievements:

Angew. Chem. Int. Ed .: Regulating Lithium Ion Solvation Layer to Enhance Lithium Metal Battery Stability

Professor Zhang Qiang‘s group at Tsinghua University improved the uniformity of SEI and lithium deposition by adjusting the composition and structure of the lithium ion solvation layer in the liquid electrolyte, thereby enhancing the cycle stability of lithium metal batteries in the liquid electrolyte. In the liquid electrolyte, the components of SEI are mainly derived from the solvated layer of lithium ions. Therefore, regulating the lithium ion solvation layer can significantly improve the uniformity of SEI and inhibit the formation of lithium dendrites. In this work, fluoroethylene carbonate (FEC) and lithium nitrate (LiNO ₃ ) are introduced into the electrolyte at the same time through the solvation of a mixed solution of ether esters, and the composition and structure of the solvated layer of lithium ions are changed to generate rich The SEI of LiF and LiN _x O _y enhance the uniformity of SEI and obtain a uniform lithium deposition morphology. The electrolyte can be used in button and soft-pack batteries to achieve high coulomb efficiency and long cycle life, and can run stably under low and high temperature conditions, which greatly improves the cycle stability of lithium metal batteries. Computational simulation of molecular dynamics and first-principles, further revealed the composition and structure of the solvated layer of lithium ions in the new electrolyte, strengthened people‘s understanding of the solvated layer at the molecular level, and provided a basis for the subsequent design of electrolyte New ideas. Related results were published on Angew. Chem. Int. Ed. Under the title " Highly Stable Lithium Metal Batteries Enabled by Regulating the Solvation of Lithium Ions in Nonaqueous Electrolytes " .

Literature link: Highly Stable Lithium Metal Batteries Enabled by Regulating the Solvation of Lithium Ions in Nonaqueous Electrolytes (Angew. Chem. Int. Ed. 2018, DOI: 10.1002 / anie.201801513, the first author is Zhang Xueqiang, and the corresponding author is Professor Zhang Qiang)

Adv. Energy Mater .: Conductive and catalytic three-phase interface for uniform nucleation and controlled growth of Li2S in lithium-sulfur batteries

Tsinghua University Zhang Qiang and Beijing Institute of Technology Huang Jiaqi‘s research team collaborated to propose a three-phase interface with strong chemical adsorption, high electrical conductivity, and high electrocatalytic activity. This coordinated three-phase interface can effectively adjust the kinetic behavior of soluble lithium polysulfide, thereby achievinguniform nucleation and controlled growth of thedischarge product Li ₂ S. Through this unique three-phase interface forthe effective regulation ofLi ₂ S deposition, at a rate of up to 6C, the lithium-sulfur battery exhibits aspecific discharge capacityof up to 916 mAh g ⁻¹ , even after 500 cycles at 6C Get up to 459 mAh g ⁻¹ specific capacity. This work created a new idea for energy chemistry to regulate the electrochemical redox reaction process from the perspective of interface chemistry, and also promoted the development of energy storage and conversion systems based on multi-electron redox reactions. Related research results werepublished on Adv. Energy Mater. Under the title of Conductive and Catalytic Triple ‐ Phase Interfaces Enabling Uniform Nucleation in High ‐ Rate Lithium–Sulfur Batteries .

Literature link: Conductive and Catalytic Triple-Phase Interfaces Enabling Uniform Nucleation in High-Rate Lithium–Sulfur Batteries

Joule: Composite lithium metal negative electrode for molten carbon filled with coral-like carbon fibers

Professor Zhang Qiang‘s research team at Tsinghua University published an article entitled "Coralloid Carbon Fiber-Based Composite Lithium Anode for Robust Lithium Metal Batteries" in the new journal of the energy sector under Cell Press. The surface is modified to a lithium-friendly surface, so that liquid molten metal lithium can be quickly sucked into the carbon fiber skeleton (CF / Ag) with a silver coating to produce a high-performance composite lithium metal anode (CF / Ag-Li). The silver coating on the one hand can modify any conductive skeleton into a lithium-philic conductive skeleton that can siphon liquid molten lithium, on the other hand, it can also reduce the metal lithium deposition overpotential, and obtain excellent cycle stability and branchlessness at high rates. The crystal has no cyclic appearance of "dead lithium". The designed composite lithium metal negative electrode can also be directly assembled with a sulfur positive electrode and a lithium iron phosphate positive electrode into a lithium-sulfur battery and a lithium iron phosphate battery with excellent performance.

Literature links: Zhang R, Chen X, Shen X, Zhang XQ, Chen XR, Cheng XB, Yan C, Zhao CZ, Zhang Q. Coralloid Carbon Fibers based Composite Lithium Anode for Robust Lithium Metal Batteries. Joule 2018, 10.1016 / j. joule.2018.02.001.

Angewandte Chemie-International Edition: incorporating lithium nitrate into carbonate electrolyte for high voltage lithium metal batteries

Researcher Huang Jiaqi of Beijing Institute of Technology ( corresponding author ) and Professor Zhang Qiang of Tsinghua University introduced a strategy of introducing a small amount of copper fluoride (CuF ₂ ) as a dissolution accelerator to make LiNO3 directly soluble in the ethylene carbonate / diethyl carbonate electrolyte in. As the solvation structure of the solution changed, the insolubility of LiNO ₃ in the carbonate electrolyte also changed. Therefore, LiNO ₃ can protect Li metal anodes in high-voltage Li metal batteries. When a LiNi _0.8 0Co _0.15 Al _0.05 O ₂ cathode is paired with a Li metal anode, the battery exhibits a very high capacity retention rate and the average Coulombic efficiency is higher than 99.5% under a cycle at 0.5C. This work expresses a deep understanding of the chemistry of solvents containing LiNO ₃ carbonate electrolytes, and demonstrates a lithium metal anode compatible system that combines both high voltage and safety in a carbonate electrolyte system. Related research results were published on Angewandte Chemie-International Edition under the title " Solvation Chemistry of Lithium Nitrate in Carbonate Electrolyte for High-Voltage Lithium Metal Battery " .

Literature link: " Solvation Chemistry of Lithium Nitrate in Carbonate Electrolyte for High-Voltage Lithium Metal Battery " (Angew. Chem. Int. Ed. DOI: 10.1002 / anie.201807034)

Angew. Chem. Int. Ed.: Supramolecular Capsules for Reversible Storage / Transfer of Polysulfides in Lithium-Sulfur Batteries

Professor Zhang Qiang (corresponding author) from Tsinghua University introduced the use of cucurbituron (CB) as a supramolecular capsule for the reversible storage / release of soluble polysulfides in lithium-sulfur (Li-S) batteries to control the Dissolved and published a research paper entitled " A Supramolecular Capsule for Reversible Polysulfide Storage / Delivery in Lithium-Sulfur Batteries " on Angew. Chem. Int. Ed . The Li-S battery using the supramolecular capsule separator coating has a higher Coulomb efficiency, and the capacity is increased from 300 mAh · g ^-1 to 900 mAh · g ^-1 under 4.2 mg · cm ^-2 sulfur load , and the performance is significantly improved . The application of supramolecular capsules provides a new perspective for deep understanding of complex multi-electron conversion reactions. It is an efficient strategy to improve the performance of Li-S batteries and similar application systems.

Literature link: A Supramolecular Capsule for Reversible Polysulfide Storage / Delivery in Lithium-Sulfur Batteries (Angew. Chem. Int. Ed., 2017, DOI: 10.1002 / anie.201710025)

Adv. Mater .: Three-dimensional mesoporous van der Waals heterojunction for electrocatalysis

The team of Professor Zhang Qiang of Tsinghua University and Professor Zhang Bingsen of the Institute of Metal Research, Chinese Academy of Sciences , published the latest research results " 3D Mesoporous van der Waals Heterostructures for Trifunctional Energy Electrocatalysis " on Adv . In this paper, the researchers prepared a three-dimensional mesoporous graphene / nitrogen-doped molybdenum sulfide van der Waals heterojunction (G @ N-MoS ₂ ) by a two-step chemical vapor deposition (CVD) method . The study uses mesoporous magnesium oxide as a template, firstly CVD a layer of mesoporous graphene skeleton with methane as a carbon source, and then introduces a Mo / S / N source to grow in situ nitrogen doped molybdenum sulfide nanosheets on the graphene skeleton to form a layer The van der Waals heterojunction also replicated the three-dimensional mesoporous structure of magnesia. This material design and synthesis idea can not only effectively control the physical structure and electronic structure of each component (three-dimensional mesopores / doping), but also can build hybrid materials with strong coupling at the interface (Van Dehua heterojunction). Due to its special structure and electronic regulation, G @ N-MoS ₂ exhibits highly efficient three-functional electrocatalytic performance, the hydrogen evolution (HER) activity on the N-MoS ₂ side is significantly improved, and the oxygen reduction (ORR) on the graphene side And oxygen precipitation (OER) activity is also greatly enhanced. The design concept and synthesis methodology of the material provide new ideas and inspiration for the research of two-dimensional materials and energy electrocatalysis. The authors of this research are Tang Cheng, Zhong Ling, Zhang Bingsen, Wang Haofan, and Zhang Qiang (corresponding authors).

Literature link : 3D Mesoporous van der Waals Heterostructures for Trifunctional Energy Electrocatalysis , (Adv. Mater., 2017, DOI: 10.1002 / adma.201705110)

AM: a dual-function perovskite-type accelerator for stabilizing polysulfides in lithium-sulfur batteries

Professor Zhang Qiang from the Department of Chemical Engineering of Tsinghua University and Huang Jiaqi‘s research group from Beijing Institute of Technology published a research paper entitled "A Bifunctional Perovskite Promoter for Polysulfide Regulation toward Stable Lithium–Sulfur Batteries" in Advanced Materials, and proposed a dual-function perovskite Nanoparticles with a structure of Ba _0.5 Sr _0.5 Co _0.8 Fe _0.2 O _{3 − δ} (denoted as PrNPs) can be used as accelerators to fix LiPSs, promote LiPS transformation, and regulate Li ₂ S deposition.

Literature link: A Bifunctional Perovskite Promoter for Polysulfide Regulation toward Stable Lithium–Sulfur Batteries (Adv. Mater, 2017, DOI: 10.1002 / adma.201705219)

Nat. Commun: Surface defect-rich perovskite hydroxide under p-region metal regulation-Electrocatalytic oxygen evolution beyond IrO2

The team of Zhang Qiang (corresponding author) of the Department of Chemical Engineering of Tsinghua University and Zhang Bingsen‘s team of the Institute of Metal Research of the Chinese Academy of Sciences jointly proposed the concept of metal regulation in the p-region to prepare a surface defect-rich perovskite water oxidation catalyst. The p-region metal refers to a metal element in the third main group to the seventh main group of the periodic table of the elements. Under certain conditions (such as in an alkaline electrolyte solution), it can be lost from the solid phase surface of the catalyst to form a large number of surface defects. Using this feature, the authors designed and prepared a tin-nickel-iron (SnNiFe) ternary perovskite system, in which tin was introduced as a typical p-region metal. Under the conditions of electrochemical activation, tin on the surface of perovskite is lost and a large number of oxygen vacancies are generated as highly active surface defect sites. The activated perovskite exhibits ultra-high oxygen precipitation activity. Its overpotential at a current density of 10 mA cm ^-2 is only 350 mV. Compared with the precious metal IrO ₂ catalyst, the overpotential is reduced by 20 mV under the same conditions. The reaction kinetics also improved significantly. At the same time, the stability of oxygen evolution of SnNiFe catalyst is also better than IrO _2. After operating at 20,000 s at a constant potential with an initial current density of 10 mA cm ^-2 , SnNiFe can maintain 60% of the initial current density. ₂ can only keep 40%. The author further constructs an "oxygen pool" model to describe the electrochemical process of defect-rich surfaces, in which reactants merge into the surface oxygen pool and accelerate the electrochemical reaction eventually leading to the precipitation of products from the oxygen pool. The research results were published in Nature Communications under the title " Regulating p-block metals in perovskite nanodots for efficient electrocatalytic water oxidation " .

Reference link: Regulating p-block metals in perovskite nanodots for efficient electrocatalytic water oxidation (Nat. Commun., 2017 , 8, 934, DOI: 10.1038 / s41467-017-01053-x)

PNAS: anion-immobilized flexible composite electrolyte protects lithium metal anodes

Tsinghua University Zhang Qiang‘s research team PNAS (Proceedings of the National Academy of Sciences of the United States of America) published an article that proposed the use of anion-fixed inorganic ceramic materials (aluminum-doped Li _6.75 La ₃ Zr _1.75 Ta _0.25 O ₁₂ , LLZTO) Build a flexible composite solid electrolyte (PEO-LiTFSI-LLZTO, PLL) membrane with an organic polymer material (PEO-LiTFSI) to inhibit the growth of metal lithium negative electrode dendrites. The composite electrolyte anion (TFSI ^- ) is a polymer matrix and ceramic filler bound, form a space charge layer of uniformly distributed, uniform distribution of lithium ions and thus the guide to achieve deposition of metal lithium dendrite-free. The dissociation of anions and lithium ions in the lithium salt helps to reduce the crystallinity of the polymer, and a fast and stable lithium ion transmission channel is constructed. The addition of the inorganic fast ionic conductor LLZTO will broaden the electrochemical window of the polymer electrolyte and show excellent electrolyte-electrode interface stability and electrochemical cycling performance. The composite solid electrolyte membrane provides a barrier at extremely high temperatures, blocks positive and negative short circuits, and improves battery cycle efficiency and safety.

Literature link: An Anion-Immobilized Composite Electrolyte for Dendrite-Free Lithium Metal Anodes. Proceedings of the National Academy of Sciences of the United States of America (PNAS, 2017, doi: 10.1073 / pnas.1708489114)

Nature Communications: Nanodiamonds inhibit lithium dendrite growth

From Professor Zhang Qiang Tsinghua University (Corresponding author) research team, Drexel University Professor Yury Gogotsi (corresponding author) research team and research professor at Huazhong University of Science JIANG Jianjun team in Nature Communications entitled the " nanodiamonds the suppress value at The Growth of Lithium dendrites "article. This article reports a co-deposition method inspired by the electroplating industry, using nanodiamond as an additive, and adding it to the electrolyte of a classic lithium ion battery (LiPF ₆ as the solute and EC / DEC as the solvent) to suppress lithium dendrite Growth. By constructing a two-electrode system similar to an electrolytic cell (copper foil is used as a positive electrode, lithium foil is used as a negative electrode), ODA functional group-modified nano-diamond particles are added and dispersed in an ester-based electrolyte. This results in uniform and non-dendritic lithium deposition and stable electrochemical cycling performance.

Literature link: Nanodiamonds suppress the growth of lithium dendrites (Nat. Commun. 2017, 8, 336, doi: 10.1038 / s41467-017-00519-2)

Adv. Mater .: Application of thermal exfoliation layered MOF in lithium-sulfur batteries

Nanocarbons with a two-dimensional graphene-like / graphene oxide structure have high physical and chemical characteristics due to their high aspect ratio, making them great applications in electrochemical energy storage, gas adsorption and separation, and catalysis. Recently, a professor at Tsinghua University, Zhang Qiang . Mater Adv . On issued a document, entitled " Thermal Exfoliation of Layered Metal-Organic Frameworks INTO Ultrahydrophilic Graphene Stacks and Their Applications in Li-S Batteries" . In this work, copper salt 4,4‘-bipyridine MOF was used to form a two-dimensional layered structure. In the two-dimensional structure, [Cu ₂ Cl ₂ C ₁₀ H ₈ N ₂ ] _n crystals are formed by π-π conjugate interaction . Due to the weak van der Waals force of the crystal, it is easy to be thermally peeled into a polymer crystal with a thickness of about 10 μm and a nanometer size.

Article link: Thermal Exfoliation of Layered Metal–Organic Frameworks into Ultrahydrophilic Graphene Stacks and Their Applications in Li–S Batteries ( Adv. Mater. 2017, 10.1002 / adma.201702829)

Adv. Mater: Bifunctional transition metal hydroxysulfide-room temperature vulcanization and its application in zinc-air batteries

Professor Zhang Qiang (corresponding author) of Tsinghua University used a concise room temperature vulcanization method to make use of the difference in solubility products of metal sulfides and metal hydroxy compounds to immerse metal hydroxy compounds in high-concentration sulfur ion solutions to prepare metal hydroxy sulfides. The method avoids the problems that the traditional hydrothermal method or chemical vapor deposition method requires high temperature and organic contamination of the reactants for preparing the sulfide. The reaction can proceed at room temperature, avoiding agglomeration. The research group took cobalt aluminum and cobalt iron hydroxy compounds as representatives, prepared materials cobalt aluminum hydroxy sulfide and cobalt iron hydroxy sulfide, and performed XPS, XRD, SEM, TEM and other characterizations and corresponding electrochemical tests, which proved the effectiveness of the method. Sex. Among them, the relative standard hydrogen electrode potential corresponding to the current density of 10 mA / cm ² during the OER process of cobalt iron hydrosulfide is 1.588V, and the half-wave potential of the ORR process is corresponding to the standard hydrogen electrode potential 0.721V. Compared with platinum and iridium-based electrocatalysts in zinc-air batteries, this substance corresponds to a smaller overpotential of 0.86V at 20mA / cm ² , a higher specific capacity of 898mAh / g, and a long cycle life. Therefore, it is used as an air electrode for a rechargeable zinc-air battery. The achievement was published in the journal Advanced Materials under the title "Bifunctional Transition Metal Hydroxysulfides: Room-Temperature Sulfurization and Their Applications in Zn-Air Batteries".

Literature link: Bifunctional Transition Metal Hydroxysulfides: Room-Temperature Sulfurization and Their Applications in Zn–Air Batteries (Adv. Mater. 2017, DOI: 10.1002 / adma.201702327)

Angew. Chem. Int. Ed .: Lithophilic conductive framework regulates lithium nucleation

Zhang Qiang‘s research team at Tsinghua University published an article titled "Lithiophilic Sites in Doped Graphene Guide Uniform Lithium Nucleation for Dendrite-Free Lithium Metal Anode" in Angewandte Chemie International Edition. Nitrogen-doped graphene (NG) was used as the three-dimensional conductive skeleton in the article. In the battery electrode, this three-dimensional conductive skeleton combines the advantages of the high specific surface area of the graphene material. The introduction of nitrogen-doped sites improves the lithium-philicity of the material, reduces the resistance to metal lithium deposition, and increases the nucleation sites. Growth makes the battery‘s Coulomb efficiency more than 98% to about 200 turns.

Literature links: Zhang R, Chen XR, Chen X, Zhang XQ, Cheng XB, Yan C, Zhang Q *. Lithiophilic Sites in Doped Graphene Guide Uniform Lithium Nucleation for Dendrite-Free Lithium Metal Anodes . Angewandte Chemie Interational Edition . 2017, doi : 10.1002 / anie.201702099.

Chem: implantable solid electrolyte interface film inhibits dendrite growth

Professor Zhang Qiang‘s research team at Tsinghua University and his collaborators at Henan Normal University used electrochemical deposition to pre-deposit a stable solid electrolyte interface film on the surface of metallic lithium, and use this interface film to protect lithium-sulfur and lithium-ternary batteries Metal lithium negative electrode, to obtain very stable battery cycling performance. The solid electrolyte interface film is obtained by a constant current electrochemical deposition method in a composite electrolyte additive of Li ₂ S ₅ and LiNO ₃ . The obtained film layer has a double-layer structure, in which the upper layer is a solvolytic organic layer, the lower layer is an inorganic layer obtained by decomposition of an additive, and the inorganic layer is Li ₂ S, Li ₃ N, Li ₂ SO _x , LiNO _x , LiF Consists of a uniformly distributed mosaic structure. The team also demonstrated through detailed experiments that the specific species composition brought by Li ₂ S as Li ₂ S ₅ can regulate the crystallinity of the solid electrolyte interface membrane, thereby improving the lithium ion conductivity of the membrane layer.

The Li ₂ S ₅ -LiNO ₃ composite additive has the best dispersion performance in the LiTFSI-DOL / DME electrolyte system, and has also achieved excellent battery cycle performance in lithium-sulfur batteries. However, currently commercially available high-capacity cathode materials such as ternary lithium-rich phase oxides mainly use carbonate-based electrolyte systems such as EC / DEC and the like. Polysulfides such as Li ₂ S ₅ will react with carbonate electrolytes, and the dissolution and dispersion properties of LiNO ₃ in such electrolytes are also poor. These problems severely limit polysulfide electrolytes in ternary lithium-rich anodes. Application in materials. In order to separate the battery activation process from the cyclic process and obtain a lithium metal negative electrode that can be stably circulated in all lithium metal batteries in the system, the group pioneered the electrodeposition method to pre-deposit a layer of negative electrode on the surface of the lithium sheet. Protective layer. This protective layer can not only achieve stable cycling of lithium metal negative electrodes in lithium-sulfur batteries, but also obtain excellent cycling performance in lithium-ternary batteries.

Literature link : Implantable Solid Electrolyte Interphase in Lithium Metal Batteries. (Chem, 2017, DOI: 10.1016 / j.chempr.2017.01.003)

JACS: Spatial Heterogeneity Control Enables Ultra-Long Cycle Performance for High-Load Sulfur Electrodes

Professor Zhang Qiang (corresponding author) from Tsinghua University and others have introduced an external healing agent, polysulfide, to simulate the process of biological self-healing--fibrinolysis--to make the sulfur particulate (SMiP) cathode work stably. An optimal capacity (~ 3.7 mAh cm ^-2 ) with almost no decay after 2000 cycles under a high load of 5.6 mg _(S) cm ^-2 was obtained . The inert SMiP is activated by the dissolution of the polysulfide, and the unstable phase transfer is mediated by the spatial heterogeneity of the polysulfide, which makes the solid compound nucleate and grow uniformly.

Literature link : Healing High-Loading Sulfur Electrodes with Unprecedented Long Cycling Life: Spatial Heterogeneity Control (J. Am. Chem. Soc., 2017, DOI : 10.1021 / jacs.6b12358)

Adv. Mater .: Electrocatalyst for nano-carbon material oxygen reduction: doping, edge, defect

On January 9th, Advanced Materials published on-line analysis of the research progress of carbon reduction of carbon materials oxygen reduction electrocatalysis " Nanocarbon for Oxygen Reduction Electrocatalysis: Dopants, Edges, and Defects " by Tsinghua University‘s research group (corresponding author) online .

Recently, Professor Zhang Qiang Tsinghua University research group to address these issues Carbon materials, controversy, from doping, edge defect analysis of the origin of the active carbon material such as a comprehensive summary of aspects of the system are discussed in terms of the electronic structure of the spin density doping The adsorption mechanism of oxygen reduction intermediates , edges, and defects , and OO bond cleavage were discussed in depth. This report has great guiding significance for understanding the catalytic process of non-metal oxygen reduction.

Literature link: Nanocarbon for Oxygen Reduction Electrocatalysis: Dopants, Edges, and Defects(Adv. Mater. 2017, DOI: 10.1002 / adma.201604103)

Summary:

Adv Energy Mater: review of functional binders for lithium-sulfur batteries

Lithium-sulfur (Li-S) batteries have a very high theoretical specific capacity (1675 mAhg ^-1 ), and are rich in sulfur content and low in price. They are widely considered to be the development direction of future large-scale energy storage applications. Generally, the positive electrode in a Li-S battery mainly includes four components: a current collector, an electrochemically active sulfur material, a conductive carbon additive, and a polymer binder. Polymer binders are generally inert, non-conductive, and are usually added to the electrode in small doses. However, the polymer binder plays an indispensable role in the sulfur cathode, including: 1) ensuring close contact between the active sulfur particles and the conductive carbon body; 2) providing a strong adhesion to the S / C The active material is bonded to the current collector; 3) The volume change of sulfur during charge and discharge is relieved and the integrity of the electrode structure is maintained. Especially in the case of high area sulfur loading, the role of the polymer binder is critical to maintaining the structural stability of the positive electrode; 4) due to the insulating properties of elemental sulfur and discharge products, polymer adhesion was developed Binders to promote Li ion transport and electron transfer in sulfur cathodes; In addition, for the shuttle effect in Li-S batteries, functional conjugates capable of interacting with polysulfides can also be introduced, 5) capture of soluble polysulfides 6) Promote the redox reaction kinetics of polysulfide, 7) Finally adjust the dissolution and diffusion of soluble polysulfide intermediates.

Zhang Qiang, a professor of Tsinghua University , Professor Chen Renjie Beijing Institute of Technology , Huang Jiaqi researcher at the Joint University of Tokyo professor xiang rong (co-author) in Advanced Energy Materials wrote a paper entitled the " A Review of Functional Binders in Lithium - Sulfur Batteries " review article. This review focuses on the functions and effects of polymer binders, systematically summarizes recent advances in polymer binder research in sulfur cathodes, and classifies binders based on their main functions, including Mechanical properties, electrical / ionic conductivity, polysulfide adjustment and other special functions. In addition, the rational design principles of functional adhesives are proposed. Finally, the key challenges and prospects of high-performance adhesive design are presented.

Literature link: “ A Review of Functional Binders in Lithium–Sulfur Batteries ” (Adv. Energy Mater.DOI: 10.1002 / aenm.201802107)

Chem Review: Energy Chemistry in the "Marriage" of Solid Electrolytes and Metal Lithium

Recently, the team of Professor Zhang Qiang of Tsinghua University combed the material and interface chemistry problems in the matching process between lithium metal electrodes and solid electrolytes, and published a title entitled "Recent Advances in Energy Chemistry"

Between Solid-State Electrolyte and Safe Lithium-Metal Anodes ". In this review, first introduce the problems existing in the matching of solid electrolytes and metallic lithium electrodes. Second, the author introduces the basics that need attention when solving these problems Principles and rules. Based on these basic principles and methods, the author summarizes the high-efficiency strategies proposed in recent years to improve the safety and life of solid metal lithium batteries. Finally, the author discusses these protection strategies, The research and development direction are prospected.

Literature links: Xin-Bing Cheng, Chen-Zi Zhao, Yu-Xing Yao, He Liu, Qiang Zhang, Recent Advances in Energy Chemistry between Solid-State Electrolyte and Safe Lithium-Metal Anodes (Chem, 2018, https: // doi .org / 10.1016 / j.chempr.2018.12.002)

Materials Today review: The status and future prospects of combined application of theory and experiment in lithium-sulfur batteries

Professor Zhang Qiang‘s group from the Department of Chemical Engineering of Tsinghua University was invited to publish a review article entitled " Combining Theory and Experiment in Lithium–Sulfur Batteries: Current Progress and Future Perspectives " in the top international journal Materials Today . This review systematically summarizes the comprehensive application of theoretical calculations and experimental characterizations in lithium-sulfur batteries. It further analyzes the theory and the aspects from X-ray diffraction, Raman spectroscopy, infrared spectroscopy, X-ray absorption spectroscopy, binding energy and nuclear magnetic fields. How experiments are combined and their difficulties provide important guidance and research ideas for the future integration of theories and calculation methods in the field of lithium-sulfur batteries and related energy storage and conversion. Professor Zhang Qiang and Berkeley, University of California, Department of Materials Engineering of Kristin A. Persson professor for the article (Corporate Communication) author, the first author is Tsinghua University Department of Chemical Engineering Dr. Chen Xiang , the second author to the University of California, Berkeley Materials Engineering Department of Dr. Hou Tingzheng.