Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural ...Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN.展开更多
Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmis...Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmission electron microscopy,and the mechanical and thermal properties of th e composites were also tested. The results showed that the silicate layers were delam inated or partially exfoliated in the PVC matrix. The impact strength of the mat erial with 2 1% MMT was almost two times as high as that of pure PVC, while the tensi le strength decreased little. However, the mechanical strength of the composites began to decrease with further increasing the amount of MMT. The TGA resul ts showed that the temperature,at which a 50% weight loss of the composites occurred,was higher than that of pure PVC. The vicat softening temperatures of composites were enhanced with increasing MMT content.展开更多
基金financial support from the National Natural Science Foundation of China(No.52377220)the Natural Science Foundation of Hunan Province,China(No.kq2208265)。
文摘Sc and Zn were introduced into O3-NaMn_(0.5)Ni_(0.5)O_(2)(NaMN)using the combination of solution combustion and solid-state method.The effect of Sc and Zn dual-substitution on Na^(+) diffusion dynamics and structural stability of NaMN was investigated.The physicochemical characterizations suggest that the introduction of Sc and Zn broaden Na^(+) diffusion channels and weaken the Na—O bonds,thereby facilitating the diffusion of sodium ions.Simulations indicate that the Sc and Zn dual-substitution decreases the diffusion barrier of Na-ions and improves the conductivity of the material.The dual-substituted NaMn_(0.5)Ni_(0.4)Sc_(0.04)Zn_(0.04)O_(2)(Na MNSZ44)cathode delivers impressive cycle stability with capacity retention of 71.2%after 200 cycles at 1C and 54.8%after 400 cycles at 5C.Additionally,the full cell paired with hard carbon anode exhibits a remarkable long-term cycling stability,showing capacity retention of 64.1%after 250 cycles at 1C.These results demonstrate that Sc and Zn dual-substitution is an effective strategy to improve the Na^(+) diffusion dynamics and structural stability of NaMN.
文摘Nanocomposites were prepared by a simple technique of emulsion polymerization using VC monomer and Na + montmorillonite. The nano structure of the composites was studied with the aid of X ray diffraction and t ransmission electron microscopy,and the mechanical and thermal properties of th e composites were also tested. The results showed that the silicate layers were delam inated or partially exfoliated in the PVC matrix. The impact strength of the mat erial with 2 1% MMT was almost two times as high as that of pure PVC, while the tensi le strength decreased little. However, the mechanical strength of the composites began to decrease with further increasing the amount of MMT. The TGA resul ts showed that the temperature,at which a 50% weight loss of the composites occurred,was higher than that of pure PVC. The vicat softening temperatures of composites were enhanced with increasing MMT content.
