Lithium-sulfur(Li-S)batteries have attracted enormous interest due to their super-high theoretical energy density(2600 W·h/kg)in recent years.However,issues such as lithium dendrites and the shuttle effect severe...Lithium-sulfur(Li-S)batteries have attracted enormous interest due to their super-high theoretical energy density(2600 W·h/kg)in recent years.However,issues such as lithium dendrites and the shuttle effect severely hampered the large-scale application of Li-S batteries.Herein,a novel bifunctional gel polymer electrolyte,poly(N,Ndiallyl-N,N-dimethylammonium bis(trifluoromethylsulfonylimide))-P(VDF-HFP)(PDDA-TFSI-P(VDF-HFP),PTP),was prepared by anion exchange reaction to tackle the above problems.Benefited from the interaction between TFSI-and quaternary ammonium ion in PTP,a higher lithium-ion transference number was obtained,which could availably protect Li metal anodes.Meanwhile,due to the adsorption interactions between PDDA-TFSI and polysulfides(LiPSs),the shuttle effect of Li-S batteries could be alleviated effectively.Consequently,the Li symmetric batteries assembled with PTP cycled more than 1000 h and lithium metal anodes were protected effectively.Li-S batteries assembled with this polymer electrolyte show a discharge specific capacity of 813 mA·h/g after 200 cycles and 467 mA·h/g at 3 C,exhibiting excellent cycling stability and C-rates performance.展开更多
A novel unsymmetrical cyanine dye(noted as CD) was applied to dye sensitized nanoporous TiO 2 photoelectrochemical cells. The incident photon to electron conversion efficiency up to 84 34% was achieved, which is notab...A novel unsymmetrical cyanine dye(noted as CD) was applied to dye sensitized nanoporous TiO 2 photoelectrochemical cells. The incident photon to electron conversion efficiency up to 84 34% was achieved, which is notably high for cells employing pure organic dyes. To circumvent the sealing difficulties present in wet type cells, the solid state cell was fabricated using poly(ethyleneoxide)(PEO) based gel network polymer electrolyte as charge transfer material between two electrodes. The resulting solid state cell had an energy conversion efficiency of 0 86%, with open circuit voltage of 0 53 V and short circuit current density of 0 96 mA/cm 2 under 38 1 mW/cm 2 white light illumination. The results show that the gel network polymer electrolyte is appropriate for assembling solid state photoelectrochemical cells.展开更多
基金Project(21935006)supported by the National Natural Science Foundation of China。
文摘Lithium-sulfur(Li-S)batteries have attracted enormous interest due to their super-high theoretical energy density(2600 W·h/kg)in recent years.However,issues such as lithium dendrites and the shuttle effect severely hampered the large-scale application of Li-S batteries.Herein,a novel bifunctional gel polymer electrolyte,poly(N,Ndiallyl-N,N-dimethylammonium bis(trifluoromethylsulfonylimide))-P(VDF-HFP)(PDDA-TFSI-P(VDF-HFP),PTP),was prepared by anion exchange reaction to tackle the above problems.Benefited from the interaction between TFSI-and quaternary ammonium ion in PTP,a higher lithium-ion transference number was obtained,which could availably protect Li metal anodes.Meanwhile,due to the adsorption interactions between PDDA-TFSI and polysulfides(LiPSs),the shuttle effect of Li-S batteries could be alleviated effectively.Consequently,the Li symmetric batteries assembled with PTP cycled more than 1000 h and lithium metal anodes were protected effectively.Li-S batteries assembled with this polymer electrolyte show a discharge specific capacity of 813 mA·h/g after 200 cycles and 467 mA·h/g at 3 C,exhibiting excellent cycling stability and C-rates performance.
文摘A novel unsymmetrical cyanine dye(noted as CD) was applied to dye sensitized nanoporous TiO 2 photoelectrochemical cells. The incident photon to electron conversion efficiency up to 84 34% was achieved, which is notably high for cells employing pure organic dyes. To circumvent the sealing difficulties present in wet type cells, the solid state cell was fabricated using poly(ethyleneoxide)(PEO) based gel network polymer electrolyte as charge transfer material between two electrodes. The resulting solid state cell had an energy conversion efficiency of 0 86%, with open circuit voltage of 0 53 V and short circuit current density of 0 96 mA/cm 2 under 38 1 mW/cm 2 white light illumination. The results show that the gel network polymer electrolyte is appropriate for assembling solid state photoelectrochemical cells.