Separators play a critical role in lithium-ion batteries.However,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications und...Separators play a critical role in lithium-ion batteries.However,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh conditions.Here,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and continuously.With an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion batteries.In addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.展开更多
Lithium-sulfur(Li-S)batteries with attractive capacity give remarkable potential for prospective high-capacity application scenarios but suffer a fatal flaw of short cyclability before large-scale commercialization es...Lithium-sulfur(Li-S)batteries with attractive capacity give remarkable potential for prospective high-capacity application scenarios but suffer a fatal flaw of short cyclability before large-scale commercialization especially owing to polysulfide(Li_(2)S_(n))transmembrane shuttling.To efficiently restrain chronic Li_(2)S_(n) shuttle and expedite Li^(+)transfer,herein,a novel electriferous charge-mosaic S(TMC@Lys-Li)separator preparation approach is recommended.Interfacial polymerizations of lithiated lysine and trimesoyl chloride establish an electriferous charge-mosaic polyamide functional layer.Substituted Li within the charge-mosaic layer offers transition or replacement sites for smoothing Li^(+)migrations,which constructs efficient Li^(+)fast-transfer private channels and accelerates the Li^(+)transfer rate to 9.4 times.Negatively charged polyamide skeleton synchronously heightens Li_(2)S_(n) rejections by combining Donnan and steric effects.S(TMC@Lys-Li)replenishes Li for homogenizing Li nucleation and growth,endowing stable plating/stripping behaviors over 250 cycles for Li-Cu batteries.Assembled Li-S cells thus exhibit excellent specific capacity and cyclability at multiple application scenarios such as long periods,high areal capacity,and fast charge,holding 78.1%retention after 500 cycles at 1 C.The superior thermal stability and self-discharge of S(TMC@Lys-Li)dramatically strengthen battery thermal runaway resistance even at155℃,which ensures security for Li-S battery high-power and high-temperature operations.Above alluring features enable charge-mosaic separators to be potentially adopted in practical Li-S batteries demanding strict security,high-capacity density,and fast charge technology.展开更多
To improve the performances of HDPE-based separators, polyether chains were incorporated into HDPE membranes by blending with poly（ethylene-block-ethylene glycol） （PE-b-PEG） via thermally induced phase separation ...To improve the performances of HDPE-based separators, polyether chains were incorporated into HDPE membranes by blending with poly（ethylene-block-ethylene glycol） （PE-b-PEG） via thermally induced phase separation （TIPS） process. By measuring the composition, morphology, crystallinity, ion conductivity, etc, the influence of PE-b-PEG on structures and properties of the blend separator were investigated. It was found that the incorporated PEG chains yielded higher surface energy for HDPE separator and improved affinity to liquid electrolyte. Thus, the stability of liquid electrolyte trapped in separator was increased while the interfacial resistance between separator and electrode was reduced effectively. The ionic conductivity of liquid electrolyte soaked separator could reach 1.28 ×10^-3 S.cm^-1 at 25℃, and the electrochemical stability window was up to 4.5 V （versus Li^＋/Li）. These results revealed that blending PE-b-PEG into porous HDPE membranes could efficiently improve the performances of PE separators for lithium batteries.展开更多
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...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.展开更多
Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as p...Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as precursor. The unique and delicate structure where three-dimensional interconnected bacterial cellulose（BC） network embedded in two-dimensional GO skeleton could not only work as an effective barrier to retard polysulfide diffusion during the charge/discharge process to enhance the cyclic stability of the Li–S battery, but also offer a continuous electron transport pathway for the improved rate capability.As a result, by utilizing pure sulfur as cathodes, the Li–S batteries assembled with PBC/GO interlayer can still exhibit a capacity of nearly 600 mAh·g^-1 at 3C and only 0.055% capacity decay per cycle can be observed over 200 cycles. Additionally, the cost-efficient and environmentfriendly raw materials may enable the PBC/GO sandwich interlayer to be an advanced configuration for Li–S batteries.展开更多
Metal-organic framework(MOF)/polymer composites have attracted extensive attention in the recent years.However,it still remains challenging to efficiently and effectively fabricate these composite materials.In this st...Metal-organic framework(MOF)/polymer composites have attracted extensive attention in the recent years.However,it still remains challenging to efficiently and effectively fabricate these composite materials.In this study,we propose a facile one-pot electrospinning strategy for preparation of HKUST-1/polyacrylonitrile(PAN)nanofibrous membranes from a homogeneous stock solution containing HKUST-1 precursors and PAN.MOF crystallization and polymer solidification occur simultaneously during the electrospinning process,thus avoiding the issues of aggregation and troublesome multistep fabrication of the conventional approach.The obtained HKUST-1/PAN electrospun membranes show uniform MOF distribution throughout the nanofibers and yield good mechanical properties.The membranes are used as separators in Li-metal full batteries under harsh testing conditions,using an ultrathin Li-metal anode,a high mass loading cathode,and the HKUST-1/PAN nanofibrous separator.The results demonstrate significantly improved cycling performance(capacity retention of 83.1%after 200 cycles)under a low negative to positive capacity ratio(N/P ratio of 1.86).The improvement can be attributed to an enhanced wettability of the separator towards electrolyte stemmed from the nanofibrous structure,and a uniform lithium ion flux stabilized by the open metal sites of uniformly distributed HKUST-1 particles in the membrane during cycling.展开更多
To improve the electrolyte wettability and thermal stability of polypropylene （PP） separators, nano- SiO2/poly（vinyl alcohol）-coated PP composite separators were prepared using a simple but efficient sol-gel and d...To improve the electrolyte wettability and thermal stability of polypropylene （PP） separators, nano- SiO2/poly（vinyl alcohol）-coated PP composite separators were prepared using a simple but efficient sol-gel and dip-coating method. The effects of the tetraethoxysilane （TEOS） dosage on the morphology, wettability, and thermal stability of the composite separators were investigated using Fourier-transform infrared spectroscopy, scanning electron microscopy, and contact-angle measurements. All the composite separators gave a smaller contact angle, higher electrolyte uptake, and lower thermal shrinkage compared with the PP separator, indicating enhanced wettability and thermal stability. Unlike the case for a traditional physical mixture, Si-O-C covalent bonds were formed in the coating layer. The composite separator with a TEOS dosage of 7.5 wt% had a unique porous structure combining hierarchical pores with interstitial voids, and gave the best wettability and thermal stability. The ionic conductivity of the composite separator containing 7.5 wt% TEOS was 1.26 mS/cm, which is much higher than that of the PP separator （0.74 mS/cm）. The C-rate and cycling performances of batteries assembled with the composite separator containing 7.5 wt% TEOS were better than those of batteries containing PP separators.展开更多
Porous materials have become a burgeoning research interest in materials science because of their intrinsic porous characteristics,versatile chemical compositions,and abundant functionalities.Recently,inspired by natu...Porous materials have become a burgeoning research interest in materials science because of their intrinsic porous characteristics,versatile chemical compositions,and abundant functionalities.Recently,inspired by natural superwetting surfaces originating from the cooperation of surface energy and surface geometry,porous membranes with special wettabilities are finding emerging opportunities associated with a wide variety of environmental and energy-related applications.This review will present an overview of the state-of-the-art research on the designed fabrications and applications of superwetting porous membranes based on zeolites,metal–organic frameworks(MOFs),porous organic materials(POMs),and mesoporous materials.General synthetic strategies for the fabrication of porous membranes(e.g.,hydrothermal/solvothermal crystallization,interfacial polymerization,electrospinning,etc.),and principles for tuning the wettability of porous membranes through surface energy modulation are introduced.Furthermore,their emerging applications as oil–water separation membranes,lithium-ionbattery separators,self-cleaning layers,and anticorrosion coatings are demonstrated.Finally,we emphasize on future perspectives regarding the development of superwetting porous membranes for practical applications.展开更多
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0450402)the National Key Research and Development Program of China(Nos.2018YFE0202201 and 2021YFA0715700)+3 种基金the National Natural Science Foundation of China(Nos.22293044,U1932213,51732011,22105194,and 92163130)the Major Basic Research Project of Anhui Province(No.2023z04020009)the New Cornerstone Investigator Programcarried out at the USTC Center for Micro and Nanoscale Research and Fabrication。
文摘Separators play a critical role in lithium-ion batteries.However,the restrictions of thermal stability and inferior electrical performance in commercial polyolefin separators significantly limit their applications under harsh conditions.Here,we report a cellulose-assisted self-assembly strategy to construct a cellulose-based separator massively and continuously.With an ultrahigh ionic conductivity in electrolytes of 3.7 mS·cm^(-1) and the ability to regulate ion transport,the obtained separator is a promising alternative for high-performance lithium-ion batteries.In addition,integrated with high thermal stability,the cellulose-based separator endows batteries with high safety at high temperatures,greatly expanding the application scenarios of energy storage devices in extreme environments.
基金supported by the Natural Science Foundation of Shandong Province(ZR2022QB050)the Liaocheng University Doctoral Initial Fund(318052137)。
文摘Lithium-sulfur(Li-S)batteries with attractive capacity give remarkable potential for prospective high-capacity application scenarios but suffer a fatal flaw of short cyclability before large-scale commercialization especially owing to polysulfide(Li_(2)S_(n))transmembrane shuttling.To efficiently restrain chronic Li_(2)S_(n) shuttle and expedite Li^(+)transfer,herein,a novel electriferous charge-mosaic S(TMC@Lys-Li)separator preparation approach is recommended.Interfacial polymerizations of lithiated lysine and trimesoyl chloride establish an electriferous charge-mosaic polyamide functional layer.Substituted Li within the charge-mosaic layer offers transition or replacement sites for smoothing Li^(+)migrations,which constructs efficient Li^(+)fast-transfer private channels and accelerates the Li^(+)transfer rate to 9.4 times.Negatively charged polyamide skeleton synchronously heightens Li_(2)S_(n) rejections by combining Donnan and steric effects.S(TMC@Lys-Li)replenishes Li for homogenizing Li nucleation and growth,endowing stable plating/stripping behaviors over 250 cycles for Li-Cu batteries.Assembled Li-S cells thus exhibit excellent specific capacity and cyclability at multiple application scenarios such as long periods,high areal capacity,and fast charge,holding 78.1%retention after 500 cycles at 1 C.The superior thermal stability and self-discharge of S(TMC@Lys-Li)dramatically strengthen battery thermal runaway resistance even at155℃,which ensures security for Li-S battery high-power and high-temperature operations.Above alluring features enable charge-mosaic separators to be potentially adopted in practical Li-S batteries demanding strict security,high-capacity density,and fast charge technology.
基金financially supported by the National Natural Science Foundation of China (Nos. 20974094, U1134002)
文摘To improve the performances of HDPE-based separators, polyether chains were incorporated into HDPE membranes by blending with poly（ethylene-block-ethylene glycol） （PE-b-PEG） via thermally induced phase separation （TIPS） process. By measuring the composition, morphology, crystallinity, ion conductivity, etc, the influence of PE-b-PEG on structures and properties of the blend separator were investigated. It was found that the incorporated PEG chains yielded higher surface energy for HDPE separator and improved affinity to liquid electrolyte. Thus, the stability of liquid electrolyte trapped in separator was increased while the interfacial resistance between separator and electrode was reduced effectively. The ionic conductivity of liquid electrolyte soaked separator could reach 1.28 ×10^-3 S.cm^-1 at 25℃, and the electrochemical stability window was up to 4.5 V （versus Li^＋/Li）. These results revealed that blending PE-b-PEG into porous HDPE membranes could efficiently improve the performances of PE separators for lithium batteries.
基金Project supported by the Beijing Science and Technology ProjectChina(Grant No.Z13111000340000)+1 种基金the National Basic Research Program of China(Grant No.2012CB932900)the National Natural Science Foundation of China(Grant Nos.51325206 and 51421002)
文摘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.
基金financially supported by the Ministry of Science and Technology of China(No.2012CB933403)the National Natural Science Foundation of China(Nos.51425302 and 51302045)the Beijing Municipal Science and Technology Commission(No.Z121100006812003)
文摘Herein, a facile strategy for the synthesis of sandwich pyrolyzed bacterial cellulose（PBC）/graphene oxide（GO） composite was reported simply by utilizing the large-scale regenerated biomass bacterial cellulose as precursor. The unique and delicate structure where three-dimensional interconnected bacterial cellulose（BC） network embedded in two-dimensional GO skeleton could not only work as an effective barrier to retard polysulfide diffusion during the charge/discharge process to enhance the cyclic stability of the Li–S battery, but also offer a continuous electron transport pathway for the improved rate capability.As a result, by utilizing pure sulfur as cathodes, the Li–S batteries assembled with PBC/GO interlayer can still exhibit a capacity of nearly 600 mAh·g^-1 at 3C and only 0.055% capacity decay per cycle can be observed over 200 cycles. Additionally, the cost-efficient and environmentfriendly raw materials may enable the PBC/GO sandwich interlayer to be an advanced configuration for Li–S batteries.
基金We sincerely thank the State Key Laboratory of Chemical Engineering at Zhejiang University(No.SKL-ChE-20D01)the Program for Guangdong Introducing Innovative and Entrepreneurial Teams(No.2017ZT07C291)+1 种基金Shenzhen Science and Technology Program(No.KQTD20170810141424366)2019 Special Program for Central Government Guiding Local Science and Technology Development:Environmental Purification Functional Materials Research Platform,and Shenzhen Key Laboratory of Advanced Materials Product Engineering(No.ZDSYS20190911164401990)for supporting this research work。
文摘Metal-organic framework(MOF)/polymer composites have attracted extensive attention in the recent years.However,it still remains challenging to efficiently and effectively fabricate these composite materials.In this study,we propose a facile one-pot electrospinning strategy for preparation of HKUST-1/polyacrylonitrile(PAN)nanofibrous membranes from a homogeneous stock solution containing HKUST-1 precursors and PAN.MOF crystallization and polymer solidification occur simultaneously during the electrospinning process,thus avoiding the issues of aggregation and troublesome multistep fabrication of the conventional approach.The obtained HKUST-1/PAN electrospun membranes show uniform MOF distribution throughout the nanofibers and yield good mechanical properties.The membranes are used as separators in Li-metal full batteries under harsh testing conditions,using an ultrathin Li-metal anode,a high mass loading cathode,and the HKUST-1/PAN nanofibrous separator.The results demonstrate significantly improved cycling performance(capacity retention of 83.1%after 200 cycles)under a low negative to positive capacity ratio(N/P ratio of 1.86).The improvement can be attributed to an enhanced wettability of the separator towards electrolyte stemmed from the nanofibrous structure,and a uniform lithium ion flux stabilized by the open metal sites of uniformly distributed HKUST-1 particles in the membrane during cycling.
基金This work was supported by the Natural Science Foundation of Guangdong Province, China （No. 2016A030313475） Dongguan Science and Technology Project, China （No. 201521510201 ）, and the Project for Science and Technology of Guandong Province, China （No. 2015B010135009）. The authors claim that there are no conflicts of interest.
文摘To improve the electrolyte wettability and thermal stability of polypropylene （PP） separators, nano- SiO2/poly（vinyl alcohol）-coated PP composite separators were prepared using a simple but efficient sol-gel and dip-coating method. The effects of the tetraethoxysilane （TEOS） dosage on the morphology, wettability, and thermal stability of the composite separators were investigated using Fourier-transform infrared spectroscopy, scanning electron microscopy, and contact-angle measurements. All the composite separators gave a smaller contact angle, higher electrolyte uptake, and lower thermal shrinkage compared with the PP separator, indicating enhanced wettability and thermal stability. Unlike the case for a traditional physical mixture, Si-O-C covalent bonds were formed in the coating layer. The composite separator with a TEOS dosage of 7.5 wt% had a unique porous structure combining hierarchical pores with interstitial voids, and gave the best wettability and thermal stability. The ionic conductivity of the composite separator containing 7.5 wt% TEOS was 1.26 mS/cm, which is much higher than that of the PP separator （0.74 mS/cm）. The C-rate and cycling performances of batteries assembled with the composite separator containing 7.5 wt% TEOS were better than those of batteries containing PP separators.
基金support from the National Natural Science Foundation of China(grant nos.21621001 and 21835002)the 111 Project(no.B17020)+2 种基金the Jilin Province/Jilin University Co-construction Project-FundsNew Materials(no.SXGJSF2017-3)supporting this work.
文摘Porous materials have become a burgeoning research interest in materials science because of their intrinsic porous characteristics,versatile chemical compositions,and abundant functionalities.Recently,inspired by natural superwetting surfaces originating from the cooperation of surface energy and surface geometry,porous membranes with special wettabilities are finding emerging opportunities associated with a wide variety of environmental and energy-related applications.This review will present an overview of the state-of-the-art research on the designed fabrications and applications of superwetting porous membranes based on zeolites,metal–organic frameworks(MOFs),porous organic materials(POMs),and mesoporous materials.General synthetic strategies for the fabrication of porous membranes(e.g.,hydrothermal/solvothermal crystallization,interfacial polymerization,electrospinning,etc.),and principles for tuning the wettability of porous membranes through surface energy modulation are introduced.Furthermore,their emerging applications as oil–water separation membranes,lithium-ionbattery separators,self-cleaning layers,and anticorrosion coatings are demonstrated.Finally,we emphasize on future perspectives regarding the development of superwetting porous membranes for practical applications.
