The development of high-performance solid-state electrolytes(SSEs)capable of reconciling high ionic conductivity with robust mechanical strength is crucial for advancing safe lithium-metal batteries(LMBs).In this stud...The development of high-performance solid-state electrolytes(SSEs)capable of reconciling high ionic conductivity with robust mechanical strength is crucial for advancing safe lithium-metal batteries(LMBs).In this study,we synthesized a novel BAB-type triblock copolymer PuPyMA-b-PEO-b-PuPyMA and used it to prepare SSEs.The copolymer design incorporates polyethylene oxide(PEO)segments to achieve ionic conduction,while uracil ketone(uPy)groups are introduced to provide quadruple hydrogen bonding.This molecular architecture leverages microphase separation and supramolecular interactions to optimize performance.The optimized electrolyte,PPMP-30 with w(uPyMA)=30%,n(EO)/n(Li^(+))=25/1,exhibits outstanding comprehensive properties at room temperature:an ionic conductivity of 4.0×10^(-4)S·cm^(-1),a high Li^(+)transference number of 0.41,and an extended electrochemical stability window up to 5.6 V(vs.Li^(+)/Li).Li//Li symmetric cells demonstrate exceptional interfacial stability and lithium dendrite suppression,cycling stably for over 650 h at 0.05 mA·cm^(-2).When assembled into LiFePO_(4)//Li cells,the electrolyte enables a high initial discharge capacity(about 160 mAh·g^(-1)at 0.1 C),excellent cycling stability(85.0%capacity retention after 120 cycles),and good rate capability with significant capacity recovery upon returning to low rates.These results highlight the significant potential of this tetrahedral hydrogen-bonded block copolymer electrolyte in overcoming the ionic conductivity-mechanical strength trade-off for practical solid-state LMBs.展开更多
Modified calcium carbonate (CaCO3) nanoparticles with cubic- and spindle-like configuration were synthesized in situ by the typical bobbling (gas-liquid-solid) method. The modifiers, such as sodium stearate, octadecyl...Modified calcium carbonate (CaCO3) nanoparticles with cubic- and spindle-like configuration were synthesized in situ by the typical bobbling (gas-liquid-solid) method. The modifiers, such as sodium stearate, octadecyl dihydrogen phosphate (ODP) and oleic acid (OA), were used to obtain hydrophobic nanoparticles. The different modification effects of the modifiers were investigated by measuring the active ratio, whiteness and the contact angle. Moreover, transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetry analysis (TGA analysis) were employed to characterize the obtained products. A preliminary reaction mechanism was discussed. According to the results, the active ratio of CaCO3 modified by ODP was ca. 99.9% and the value of whiteness was 97.3% when the dosage of modifiers reached 2%. The contact angle was 122.25° for the CaCO3 modified in the presence of sodium stearate, ODP and OA. When modified CaCO3 was filled into PVC, the mechanical properties of products were improved greatly such as rupture intensity, pull intensity and fuse temperature. The compatibility and affinity between the modified CaCO3 nanoparticles and the organic matrixes were greatly improved.展开更多
Novel self-assembled calcium carbonate(CaCO3)crystals exhibiting the morphology of well-defined needles were synthesized by a simple precipitation reaction in the presence of octadecyl dihydrogen phosphate(ODP)as a cr...Novel self-assembled calcium carbonate(CaCO3)crystals exhibiting the morphology of well-defined needles were synthesized by a simple precipitation reaction in the presence of octadecyl dihydrogen phosphate(ODP)as a crystal additive.The CaCO3 obtained by this method is hydrophobic,making it likely to be used widely in industry.The resulting products were characterized by powder X-ray diffraction,field emission scanning electron microscopy,Fourier transform infrared spectroscopy and contact angle experiments.The results indicated that ODP plays an important role in determining the structure,morphology and hydrophobicity of CaCO3 crystals.展开更多
Keggin-type phenylimido-polyoxometalates α-[PM12O39NPh]3- (M = W and Mo) have been systematically investigated on the electronic structures, redox as well as nonlinear optical (NLO) properties by density functional t...Keggin-type phenylimido-polyoxometalates α-[PM12O39NPh]3- (M = W and Mo) have been systematically investigated on the electronic structures, redox as well as nonlinear optical (NLO) properties by density functional theory (DFT). The strong M≡N bond confirmed by natural bond orbital (NBO) analysis comprises one σ bond and two π bonds, the same as Mo≡N in [Mo6O18NPh]2-. Furthermore, phenylimido segment effectively modifies the electronic properties of α-[PM12O39NPh]3-. On one hand, when enlarging the inorganic cluster from {Mo6O18} to {PMo12O39}, the energy gap between HOMO and LUMO in α-[PMo12O39NPh]3- decreased, resulting in enormously anodic shift for the reduction potential, while the excitation energy is less and the total second-order polarizability β0 is up to 438.3×10?30 esu, which is nearly 10 times larger than that of [Mo6O18NPh]2-. On the other hand, when metal W in α-[PM12O39NPh]3- is substituted by Mo, the interaction between Mo and N is enhanced and the redox ability becomes stronger. The β0 value for α-[PMo12O39NPh]3- is more than 5 times higher than that of α-[PW12O39NPh]3?. It indicates that changing appropriate metal or enlarging the inorganic cluster will improve the redox properties and second-order nonlinear response. Moreover, the electron transition for three compounds mentioned above occurred mainly from organoimido segment (as the electron donor) to polyanion cluster (as the acceptor). As a result, α-[PMo12O39NPh]3- may be a promising candidate for oxidant and nonlinear optical material.展开更多
基金supported by the 2024 Capital Construction Funds within the Provincial Budget of Jilin Provincial Development and Reform Commission[2024C018-2].
文摘The development of high-performance solid-state electrolytes(SSEs)capable of reconciling high ionic conductivity with robust mechanical strength is crucial for advancing safe lithium-metal batteries(LMBs).In this study,we synthesized a novel BAB-type triblock copolymer PuPyMA-b-PEO-b-PuPyMA and used it to prepare SSEs.The copolymer design incorporates polyethylene oxide(PEO)segments to achieve ionic conduction,while uracil ketone(uPy)groups are introduced to provide quadruple hydrogen bonding.This molecular architecture leverages microphase separation and supramolecular interactions to optimize performance.The optimized electrolyte,PPMP-30 with w(uPyMA)=30%,n(EO)/n(Li^(+))=25/1,exhibits outstanding comprehensive properties at room temperature:an ionic conductivity of 4.0×10^(-4)S·cm^(-1),a high Li^(+)transference number of 0.41,and an extended electrochemical stability window up to 5.6 V(vs.Li^(+)/Li).Li//Li symmetric cells demonstrate exceptional interfacial stability and lithium dendrite suppression,cycling stably for over 650 h at 0.05 mA·cm^(-2).When assembled into LiFePO_(4)//Li cells,the electrolyte enables a high initial discharge capacity(about 160 mAh·g^(-1)at 0.1 C),excellent cycling stability(85.0%capacity retention after 120 cycles),and good rate capability with significant capacity recovery upon returning to low rates.These results highlight the significant potential of this tetrahedral hydrogen-bonded block copolymer electrolyte in overcoming the ionic conductivity-mechanical strength trade-off for practical solid-state LMBs.
基金Supported by the National Natural Science Foundation of China (Grant No. 50372025)
文摘Modified calcium carbonate (CaCO3) nanoparticles with cubic- and spindle-like configuration were synthesized in situ by the typical bobbling (gas-liquid-solid) method. The modifiers, such as sodium stearate, octadecyl dihydrogen phosphate (ODP) and oleic acid (OA), were used to obtain hydrophobic nanoparticles. The different modification effects of the modifiers were investigated by measuring the active ratio, whiteness and the contact angle. Moreover, transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetry analysis (TGA analysis) were employed to characterize the obtained products. A preliminary reaction mechanism was discussed. According to the results, the active ratio of CaCO3 modified by ODP was ca. 99.9% and the value of whiteness was 97.3% when the dosage of modifiers reached 2%. The contact angle was 122.25° for the CaCO3 modified in the presence of sodium stearate, ODP and OA. When modified CaCO3 was filled into PVC, the mechanical properties of products were improved greatly such as rupture intensity, pull intensity and fuse temperature. The compatibility and affinity between the modified CaCO3 nanoparticles and the organic matrixes were greatly improved.
基金supported by "the Eleventh Five" Science Technology Research of Jilin Education Hall(2009-200)
文摘Novel self-assembled calcium carbonate(CaCO3)crystals exhibiting the morphology of well-defined needles were synthesized by a simple precipitation reaction in the presence of octadecyl dihydrogen phosphate(ODP)as a crystal additive.The CaCO3 obtained by this method is hydrophobic,making it likely to be used widely in industry.The resulting products were characterized by powder X-ray diffraction,field emission scanning electron microscopy,Fourier transform infrared spectroscopy and contact angle experiments.The results indicated that ODP plays an important role in determining the structure,morphology and hydrophobicity of CaCO3 crystals.
基金Supported by National Natural Science Foundation of China (Grant No. 20573016)Training Fund of NENU’S Scientific Innovation Project (Grant No. NENU- STC07017)+1 种基金Science Foundation for Young Teachers of Northeast Normal University (Grant No. 20070304)Program for Changjiang Scholars and Innovative Research Team in University (PCSIRT)
文摘Keggin-type phenylimido-polyoxometalates α-[PM12O39NPh]3- (M = W and Mo) have been systematically investigated on the electronic structures, redox as well as nonlinear optical (NLO) properties by density functional theory (DFT). The strong M≡N bond confirmed by natural bond orbital (NBO) analysis comprises one σ bond and two π bonds, the same as Mo≡N in [Mo6O18NPh]2-. Furthermore, phenylimido segment effectively modifies the electronic properties of α-[PM12O39NPh]3-. On one hand, when enlarging the inorganic cluster from {Mo6O18} to {PMo12O39}, the energy gap between HOMO and LUMO in α-[PMo12O39NPh]3- decreased, resulting in enormously anodic shift for the reduction potential, while the excitation energy is less and the total second-order polarizability β0 is up to 438.3×10?30 esu, which is nearly 10 times larger than that of [Mo6O18NPh]2-. On the other hand, when metal W in α-[PM12O39NPh]3- is substituted by Mo, the interaction between Mo and N is enhanced and the redox ability becomes stronger. The β0 value for α-[PMo12O39NPh]3- is more than 5 times higher than that of α-[PW12O39NPh]3?. It indicates that changing appropriate metal or enlarging the inorganic cluster will improve the redox properties and second-order nonlinear response. Moreover, the electron transition for three compounds mentioned above occurred mainly from organoimido segment (as the electron donor) to polyanion cluster (as the acceptor). As a result, α-[PMo12O39NPh]3- may be a promising candidate for oxidant and nonlinear optical material.
