Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures....Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.展开更多
Long chain phosphate esters bearing at least one or two aryl groups have been synthesized and used for the preparation of stable multi-walled carbon nanotube (MWCNT) hybrids. The non-covalent interaction ester/MWCNT h...Long chain phosphate esters bearing at least one or two aryl groups have been synthesized and used for the preparation of stable multi-walled carbon nanotube (MWCNT) hybrids. The non-covalent interaction ester/MWCNT has been investigated by several techniques (SEM, UV-vis, 31P-NMR, RAMAN). The used phosphate ester derivatives demonstrated the ability to produce an excellent dispersion of MWCNT in CHCl3. The obtained dispersions showed a great stability from one to at least three weeks in the range of concentration considered. Thermal analysis showed an increase in the decomposition temperature for the hybrids with respect to pristine MWCNT.展开更多
A LiCaPO4:Eu2+ phosphor with high photoluminescence was synthesized using a polymerizable complex (PC) method employing a water-soluble polyethylene glycol-conjugated phosphate ester (PEG-P). PEG-P could be obtained f...A LiCaPO4:Eu2+ phosphor with high photoluminescence was synthesized using a polymerizable complex (PC) method employing a water-soluble polyethylene glycol-conjugated phosphate ester (PEG-P). PEG-P could be obtained from a reaction among polyethylene glycol 300, phosphorus pentoxide, and pyrophosphoric acid. The PEG-P prepared was stable in an aqueous condition. A transparent solution and gel were obtained when the PEG-P was used as a source of P during the PC method, whereas the use of H3PO4 caused an undesirable precipitate. The LiCaPO4:Eu2+ obtained via the PC method employing the PEG-P showed higher emission intensity than those synthesized by a solid state reaction method and the PC method employing H3PO4. The high luminescence properties of the sample synthesized using the PEG-P may be attributed to high homogeneity of constituents in the sample.展开更多
The effect of styrene on unsaturated phosphate ester polymers was investigated. Copolymerization was carried out by adding different proportions of styrene when the unsaturated phosphate was polymerized to obtain an u...The effect of styrene on unsaturated phosphate ester polymers was investigated. Copolymerization was carried out by adding different proportions of styrene when the unsaturated phosphate was polymerized to obtain an unsaturated phosphate-styrene copolymer. The structure and crosslink density of the copolymer was determined by fourier transform infrared (FTIR) spectra and gel fraction (G) testing. The heat resistance and flame retardancy of the polymer were tested by thermogravimetric (TGA) analysis, limiting oxygen index (LOI) and micro-combustion calorimeter (MCC). The infrared test proved that the styrene was successfully introduced into the polymer system. The gelation test results showed that the introduction of the rigid benzene ring increased the crosslink density of the copolymer. The tensile strength increased from 17.84 MPa to 34.63 MPa, and the impact strength remained stable within a certain range. At the same time, the solid ultraviolet absorption test results showed that the light transmittance of the materials was higher than 90%. The TG and DTG spectra showed that the heat resistance of the polymer was improved, but the residual carbon ratio was reduced from 30.47% to 25.54%. The LOI value decreased from 29.0% to 26.1%, and the UL-94 vertical burn rating was all V-0.展开更多
基金supported by the National Natural Science Foundation of China (grant No.52072322)the Department of Science and Technology of Sichuan Province (CN) (grant no.23GJHZ0147,23ZDYF0262,2022YFG0294)Research and Innovation Fund for Graduate Students of Southwest Petroleum University (No.:2022KYCX111)。
文摘Safety remains a persistent challenge for high-energy-density lithium metal batteries(LMBs).The development of safe and non-flammable electrolytes is especially important in harsh conditions such as high temperatures.Herein,a flame-retardant,low-cost and thermally stable long chain phosphate ester based(tributyl phosphate,TBP)electrolyte is reported,which can effectively enhance the cycling stability of highly loaded high-nickel LMBs with high safety through co-solvation strategy.The interfacial compatibility between TBP and electrode is effectively improved using a short-chain ether(glycol dimethyl ether,DME),and a specially competitive solvation structure is further constructed using lithium borate difluorooxalate(LiDFOB)to form the stable and inorganic-rich electrode interphases.Benefiting from the presence of the cathode electrolyte interphase(CEI)and solid electrolyte interphase(SEI)enriched with LiF and Li_(x)PO_(y)F_(z),the electrolyte demonstrates excellent cycling stability assembled using a 50μm lithium foil anode in combination with a high loading NMC811(15.4 mg cm^(-2))cathode,with 88%capacity retention after 120 cycles.Furthermore,the electrolyte exhibits excellent high-temperature characteristics when used in a 1-Ah pouch cell(N/P=0.26),and higher thermal runaway temperature(238℃)in the ARC(accelerating rate calorimeter)demonstrating high safety.This novel electrolyte adopts long-chain phosphate as the main solvent for the first time,and would provide a new idea for the development of extremely high safety and high-temperature electrolytes.
文摘Long chain phosphate esters bearing at least one or two aryl groups have been synthesized and used for the preparation of stable multi-walled carbon nanotube (MWCNT) hybrids. The non-covalent interaction ester/MWCNT has been investigated by several techniques (SEM, UV-vis, 31P-NMR, RAMAN). The used phosphate ester derivatives demonstrated the ability to produce an excellent dispersion of MWCNT in CHCl3. The obtained dispersions showed a great stability from one to at least three weeks in the range of concentration considered. Thermal analysis showed an increase in the decomposition temperature for the hybrids with respect to pristine MWCNT.
文摘A LiCaPO4:Eu2+ phosphor with high photoluminescence was synthesized using a polymerizable complex (PC) method employing a water-soluble polyethylene glycol-conjugated phosphate ester (PEG-P). PEG-P could be obtained from a reaction among polyethylene glycol 300, phosphorus pentoxide, and pyrophosphoric acid. The PEG-P prepared was stable in an aqueous condition. A transparent solution and gel were obtained when the PEG-P was used as a source of P during the PC method, whereas the use of H3PO4 caused an undesirable precipitate. The LiCaPO4:Eu2+ obtained via the PC method employing the PEG-P showed higher emission intensity than those synthesized by a solid state reaction method and the PC method employing H3PO4. The high luminescence properties of the sample synthesized using the PEG-P may be attributed to high homogeneity of constituents in the sample.
文摘The effect of styrene on unsaturated phosphate ester polymers was investigated. Copolymerization was carried out by adding different proportions of styrene when the unsaturated phosphate was polymerized to obtain an unsaturated phosphate-styrene copolymer. The structure and crosslink density of the copolymer was determined by fourier transform infrared (FTIR) spectra and gel fraction (G) testing. The heat resistance and flame retardancy of the polymer were tested by thermogravimetric (TGA) analysis, limiting oxygen index (LOI) and micro-combustion calorimeter (MCC). The infrared test proved that the styrene was successfully introduced into the polymer system. The gelation test results showed that the introduction of the rigid benzene ring increased the crosslink density of the copolymer. The tensile strength increased from 17.84 MPa to 34.63 MPa, and the impact strength remained stable within a certain range. At the same time, the solid ultraviolet absorption test results showed that the light transmittance of the materials was higher than 90%. The TG and DTG spectra showed that the heat resistance of the polymer was improved, but the residual carbon ratio was reduced from 30.47% to 25.54%. The LOI value decreased from 29.0% to 26.1%, and the UL-94 vertical burn rating was all V-0.
