A dual-regulation strategy of B/N codoped CNT-encapsulated Ni nanoparticles as a catalytic host and separator coating promises high-performance Li-S batteries

A dual-regulation strategy of adopting B/N codoped carbon nanotube-encapsulated nickel nanoparticles(Ni@BNCNT) as a sulfur host and separator coating is proposed for high-performance Li-S batteries. On the cathode side, the 3D conductive network structure of Ni@BNCNT is favorable for high sulfur utilization, and the collaboration between polar metal Ni nanoparticles(NPs) and doped B/N elements facilitates the chemical adsorption of Li polysulfides(Li PSs). In addition, these metal Ni NPs exhibit a satisfactory catalytic effect on the polysulfide conversion. Moreover, using the Ni@BNCNT interlayer can further capture the soluble Li PSs, make them convert quickly, and prevent them from diffusing toward the anode side. The Li-S batteries simultaneously equipped with a S/Ni@BNCNT cathode and Ni@BNCNT interlayer show high reversible capacity and good cycle stability. Additionally, even at a sulfur loading of 3.5 mg cm;and an electrolyte/sulfur ratio of 3 μL mg;, excellent battery performance can be achieved. We believe that this work offers a new strategy based on combining a catalytic host and separator coating to construct high-efficiency Li-S batteries.

Endoplasmic-reticulum-like catalyst coating on separator to enhance polysulfides conversion for lithium-sulfur batteries

Lithium-sulfur(Li-S)batteries with high theoretical specific energy of 2600 Wh kg^(-1) are one of promising candidates for next-generation energy storage devices.However,the severe shuttle effect of intermediate polysulfides leads to rapid capacity decay during battery cycling,especially at high sulfur loading and high current density.Herein,the MnO nanoparticles covered carbon with endoplasmic-reticulum-like structure(MnO@ERC)as separator coating for Li-S batteries is proposed.The MnO@ERC coating can act as upper current collector to enhance electrical conductivity of cathode and decrease the interface impedance of the whole battery.More importantly,both the polar MnO nanoparticles and Mn_(3)O_(4) formed at the end of the charging process can catalyze the conversion of lithium polysulfides,which is convinced by the high adsorption energy and the elongate S–S bond.As a result,Li-S batteries based on MnO@ERC coating separator showed stable cycle for 350 cycles under 0.5C,high discharge specific capacity of 783.6m Ah g^(-1) after 100 cycles at 0.2 C,534.7 m Ah g^(-1) after 100 cycles under the sulfur loading of 5.26 mg cm;and low self-discharge rate of 9.1%after resting 48 h..

Forming solid electrolyte interphase in situ in an ionic conducting Li_(1.5)Al_(0.5)Ge_(1.5)(PO_4)_3-polypropylene(PP) based separator for Li-ion batteries

A new concept of forming solid electrolyte interphases（SEI） in situ in an ionic conducting Li（1.5）Al（0.5）Ge（1.5）（PO4）3-polypropylene（LAGP-PP） based separator during charging and discharging is proposed and demonstrated. This unique structure shows a high ionic conductivity, low interface resistance with electrode, and can suppress the growth of lithium dendrite. The features of forming the SEI in situ are investigated by scanning electron microscopy（SEM） and x-ray photoelectron spectroscopy（XPS）. The results confirm that SEI films mainly consist of lithium fluoride and carbonates with various alkyl contents. The cell assembled by using the LAGP-coated separator demonstrates a good cycling performance even at high charging rates, and the lithium dendrites were not observed on the lithium metal electrode. Therefore, the SEI-LAGP-PP separator can be used as a promising flexible solid electrolyte for solid state lithium batteries.

Designing metal sulfide-based cathodes and separators for suppressing polysulfide shuttling in lithium-sulfur batteries

Lithium-sulfur(Li-S)batteries,known for their high energy density,are attracting extensive research interest as a promising next-generation energy storage technology.However,their widespread use has been hampered by certain issues,including the dissolution and migration of polysulfides,along with sluggish redox kinetics.Metal sulfides present a promising solution to these obstacles regarding their high electrical conductivity,strong chemical adsorption with polysulfides,and remarkable electrocatalytic capabilities for polysulfide conversion.In this review,the recent progress on the utilization of metal sulfide for suppressing polysulfide shuttling in Li-S batteries is systematically summarized,with a special focus on sulfur hosts and functional separators.The critical roles of metal sulfides in realizing high-performing Li-S batteries have been comprehensively discussed by correlating the materials’structure and electrochemical performances.Moreover,the remaining issues/challenges and future perspectives are highlighted.By offering a detailed understanding of the crucial roles of metal sulfides,this review dedicates to contributing valuable knowledge for the pursuit of high-efficiency Li-S batteries based on metal sulfides.

Capillary Zone Electrophoretic Separation of Basic Proteins with Coated Columns Prepared by Sol-Gel Technology

Coated capillary columns were prepared by sol-gel technology and used in the separation of basic proteins with capillary zone electrophoresis. The results indicated that a significant decrease in protein adsorption was obtained and EOF was also diminished to zero in the pH range of 3-10.

The preparation of a novel polydopamine-graft-poly(2-methyl-2-oxazoline) protein-resistant coating and its applications in protein separation

A novel polydopamine-graft-poly（2-methyl-2-oxazoline） （PDA-g-PMOXA） coating was prepared by immobilizing poly（2-methyl-2-oxazoline） （PMOXA） onto material surfaces through polydopamine （PDA） anchored coating for the first time. And then, the chemical composition, hydrophilicity, and protein-resistant properties of the PDA-g-PMOXA coating were studied using X-ray photoelectron spectroscopy （XPS）, contact angel （CA） test, surface plasmon resonance （SPR）, and quartz crystal microbalance with dissipation （QCM-D） measurement. Finally, the coating was applied to the capillary inner surface for protein separation by capillary electrophoresis （CE）.