Quasi solid-state lithium-metal batteries(QSSLMBs)hold significant promise for enhanced energy density when compared to conventional battery systems.Nevertheless,current QSSLMBs face challenges in lithium dendrites an...Quasi solid-state lithium-metal batteries(QSSLMBs)hold significant promise for enhanced energy density when compared to conventional battery systems.Nevertheless,current QSSLMBs face challenges in lithium dendrites and electrode-electrolyte interfacial side reactions driven by excessive active free solvent molecules.Herein,a metal–organic framework(MOF)with chemically grafted soft multiether molecules(D-Gluconic acid,2,4:3,5-di-O-methylene-,denoted as G)has been proposed to serve as a solid-state electrolyte(SSE).The as-obtained M-G based electrolyte(MGE)comprises structured MOF channels with semi-immobilized solvent-like sites(G molecules),which replace liquid molecules to coordinate with Li+ions.The MGE reduces the demand for solvents compared with traditional quasi-solid-state electrolytes,thus suppressing interface side reactions.This arrangement also facilitates achieving an elevated Li+transference number(0.64)and a broad electrochemical stability window(5.4 V).Ultimately,the solid-state Li//Li symmetrical battery displays an extended lifetime surpassing 1500 h under 1mA cm^(−2).The solid-state LiFePO4//Li battery utilizing the flame-retarded MGE attains an impressive capacity retention of 95.75%over 600 cycles.The MOF-based functionalization strategy introduces an innovative approach to designing a high-performance SSE for advanced solid-state lithium metal batteries.展开更多
We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nano...We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nanofluids in order to show the effect of corona structure on the phase behavior, dispersion, as well as rheology properties. Results demonstrate novel liquid-like behaviors without solvent at room temperature. Fe3O4 magnetic nanoparticles content is bigger than 8% and its size is about 23 nm. For the solvent-free nanofluids,the long chain corona has the internal plasticization, which can decrease the loss modulus of system, while the short chain of corona results in the high viscosity of nanofluids. Long alkyl chains of modifiers lead to lower viscosity and better flowability of nanofluids. The rheology and viscosity of the nanofluids are correlated to the microscopic structure of the corona, which provide an in-depth insight into the preparing nanofluids with promising applications based on their tunable and controllable physical properties.展开更多
水飞蓟素是水飞蓟种子提取出的黄酮类生物活性成分,具有保肝利胆等多种药理功能,其中水飞蓟宾活性及含量最高,本研究利用天然低共熔溶剂(Natural Deep Eutectic Solvent,NADES),对水飞蓟宾的高效提取工艺与机理进行研究。以粉碎脱脂后...水飞蓟素是水飞蓟种子提取出的黄酮类生物活性成分,具有保肝利胆等多种药理功能,其中水飞蓟宾活性及含量最高,本研究利用天然低共熔溶剂(Natural Deep Eutectic Solvent,NADES),对水飞蓟宾的高效提取工艺与机理进行研究。以粉碎脱脂后的水飞蓟种壳粉为原料,用初步筛选所得较优NADES,即:氯化胆碱+1,4-丁二醇进行提取,HPLC法测定水飞蓟宾含量,在单因素实验基础上,采用响应面法对该NADES提取水飞蓟宾工艺进行优化。结果表明:料液比1:20 g/mL,提取温度77.0℃、时间5.6 h,模型预测水飞蓟宾得率可达4.29%,与实验值4.30%基本一致。基于片段活度系数类导体屏蔽模型(Conductor-like Screening Model for Segment Activity Coefficient,COSMO-SAC),分别对水飞蓟宾和溶剂分子(NADES与传统溶剂乙醇)进行结构与能量优化,通过量子化学计算,得到水飞蓟宾在两种溶剂中的无限稀释活度系数的对数分别为-6.922和-6.043,分子间相互作用能分别为-51.62和-25.47 kJ/mol,以探讨不同溶剂提取水飞蓟宾效果差异机理。展开更多
基金supported by the National Key Research and Development Program of China(grant nos.2022YFB2402200 and 2019YFA0705600)the National Natural Science Foundation of China(grant nos.92372001,92372203,22121005,and 52072186)+1 种基金the Science and Technology Plans of Tianjin(grant no.23JCYBJC00170)the Fundamental Research Funds for the Central Universities(grant nos.63233017,63231002,and 63231198).
文摘Quasi solid-state lithium-metal batteries(QSSLMBs)hold significant promise for enhanced energy density when compared to conventional battery systems.Nevertheless,current QSSLMBs face challenges in lithium dendrites and electrode-electrolyte interfacial side reactions driven by excessive active free solvent molecules.Herein,a metal–organic framework(MOF)with chemically grafted soft multiether molecules(D-Gluconic acid,2,4:3,5-di-O-methylene-,denoted as G)has been proposed to serve as a solid-state electrolyte(SSE).The as-obtained M-G based electrolyte(MGE)comprises structured MOF channels with semi-immobilized solvent-like sites(G molecules),which replace liquid molecules to coordinate with Li+ions.The MGE reduces the demand for solvents compared with traditional quasi-solid-state electrolytes,thus suppressing interface side reactions.This arrangement also facilitates achieving an elevated Li+transference number(0.64)and a broad electrochemical stability window(5.4 V).Ultimately,the solid-state Li//Li symmetrical battery displays an extended lifetime surpassing 1500 h under 1mA cm^(−2).The solid-state LiFePO4//Li battery utilizing the flame-retarded MGE attains an impressive capacity retention of 95.75%over 600 cycles.The MOF-based functionalization strategy introduces an innovative approach to designing a high-performance SSE for advanced solid-state lithium metal batteries.
基金supported by National Natural Science Foundations(51073129 and50971104)Aeronautical Science Foundation of China(2010ZF53060)graduate starting seed fund of Northwestern Polytechnical University(Z2011012)
文摘We studied the relationship between corona structure and properties of solvent-free Fe3O4 nanofluids. We proposed a series of corona structures with different branched chains and synthesize different solvent-free nanofluids in order to show the effect of corona structure on the phase behavior, dispersion, as well as rheology properties. Results demonstrate novel liquid-like behaviors without solvent at room temperature. Fe3O4 magnetic nanoparticles content is bigger than 8% and its size is about 23 nm. For the solvent-free nanofluids,the long chain corona has the internal plasticization, which can decrease the loss modulus of system, while the short chain of corona results in the high viscosity of nanofluids. Long alkyl chains of modifiers lead to lower viscosity and better flowability of nanofluids. The rheology and viscosity of the nanofluids are correlated to the microscopic structure of the corona, which provide an in-depth insight into the preparing nanofluids with promising applications based on their tunable and controllable physical properties.
文摘水飞蓟素是水飞蓟种子提取出的黄酮类生物活性成分,具有保肝利胆等多种药理功能,其中水飞蓟宾活性及含量最高,本研究利用天然低共熔溶剂(Natural Deep Eutectic Solvent,NADES),对水飞蓟宾的高效提取工艺与机理进行研究。以粉碎脱脂后的水飞蓟种壳粉为原料,用初步筛选所得较优NADES,即:氯化胆碱+1,4-丁二醇进行提取,HPLC法测定水飞蓟宾含量,在单因素实验基础上,采用响应面法对该NADES提取水飞蓟宾工艺进行优化。结果表明:料液比1:20 g/mL,提取温度77.0℃、时间5.6 h,模型预测水飞蓟宾得率可达4.29%,与实验值4.30%基本一致。基于片段活度系数类导体屏蔽模型(Conductor-like Screening Model for Segment Activity Coefficient,COSMO-SAC),分别对水飞蓟宾和溶剂分子(NADES与传统溶剂乙醇)进行结构与能量优化,通过量子化学计算,得到水飞蓟宾在两种溶剂中的无限稀释活度系数的对数分别为-6.922和-6.043,分子间相互作用能分别为-51.62和-25.47 kJ/mol,以探讨不同溶剂提取水飞蓟宾效果差异机理。
