Recently,abundant resources,low-cost sodium-ion batteries are deemed to the new-generation battery in the field of largescale energy storage.Nevertheless,poor active reaction dynamics,dissolution of intermediates and ...Recently,abundant resources,low-cost sodium-ion batteries are deemed to the new-generation battery in the field of largescale energy storage.Nevertheless,poor active reaction dynamics,dissolution of intermediates and electrolyte matching problems are significant challenges that need to be solved.Herein,dimensional gradient structure of sheet-tube-dots is constructed with CoSe2@CNTs-MXene.Gradient structure is conducive to fast migration of electrons and ions with the association of ether electrolyte.For half-cell,CoSe2@CNTs-MXene exhibits high initial coulomb efficiency(81.7%)and excellent cycling performance(400 mAh g^-1 cycling for 200 times in 2 Ag^−1).Phase transformation pathway from crystalline CoSe2-Na2Se with Co and then amorphous CoSe2 in the discharge/charge process is also explored by in situ X-ray diffraction.Density functional theory study discloses the CoSe2@CNTs-MXene in ether electrolyte system which contributes to stable sodium storage performance owing to the strong adsorption force from hierarchical structure and weak interaction between electrolyte and electrode interface.For full cell,CoSe2@CNTs-MXene//Na3V2(PO4)3/C full battery can also afford a competitively reversible capacity of 280 mAh g^−1 over 50 cycles.Concisely,profiting from dimensional gradient structure and matched electrolyte of CoSe2@CNTs-MXene hold great application potential for stable sodium storage.展开更多
Low efficiency and spectral instability caused by the surface defects have been considerable issues for the mixed-halogen blue emitting perovskite quantum dots light-emitting diodes(PeQLEDs).Here,an in situ surface pa...Low efficiency and spectral instability caused by the surface defects have been considerable issues for the mixed-halogen blue emitting perovskite quantum dots light-emitting diodes(PeQLEDs).Here,an in situ surface passivation to perovskite quantum dots(PeQDs)is realized by introducing the metal cations competitive lattice occupancy assisted with acid-etching,in which the longchain,insulating and weakly bond surface ligands are removed by addition of octanoic acid(OTAC).Meanwhile,the dissolved A-site cations(Na^(+))compete with the protonated oleyl amine and are subsequently anchored to the surface vacancies.The preadded lead bromide,acting as inorganic ligands,demonstrates strong bonding to the uncoordinated surface ions.The as-synthesized PeQDs show the boosted photoluminescence quantum yield(PLQY)and superior stability with longer lifetime.As a result,the PeQLEDs(470 nm)based on the OTAC-Na PeQDs exhibit an external quantum efficiency of 8.42%in the mixed halogen PeQDs(CsPb(Br_(x)Cl_(1−x))_(3)).Moreover,the device exhibits superior spectra stability with negligible shift.Our competition mechanism in combination with in situ passivation strategy paves a new way for improving the performance of blue PeQLEDs.展开更多
基金financially supported by the National Natural Science Foundation of China(Grant Nos.U1632151 and 21706048)the Key Research and Development Project of Anhui Province of China(Grant No.1704a0902023)the Open Project of Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices(No.JS1802)。
文摘Recently,abundant resources,low-cost sodium-ion batteries are deemed to the new-generation battery in the field of largescale energy storage.Nevertheless,poor active reaction dynamics,dissolution of intermediates and electrolyte matching problems are significant challenges that need to be solved.Herein,dimensional gradient structure of sheet-tube-dots is constructed with CoSe2@CNTs-MXene.Gradient structure is conducive to fast migration of electrons and ions with the association of ether electrolyte.For half-cell,CoSe2@CNTs-MXene exhibits high initial coulomb efficiency(81.7%)and excellent cycling performance(400 mAh g^-1 cycling for 200 times in 2 Ag^−1).Phase transformation pathway from crystalline CoSe2-Na2Se with Co and then amorphous CoSe2 in the discharge/charge process is also explored by in situ X-ray diffraction.Density functional theory study discloses the CoSe2@CNTs-MXene in ether electrolyte system which contributes to stable sodium storage performance owing to the strong adsorption force from hierarchical structure and weak interaction between electrolyte and electrode interface.For full cell,CoSe2@CNTs-MXene//Na3V2(PO4)3/C full battery can also afford a competitively reversible capacity of 280 mAh g^−1 over 50 cycles.Concisely,profiting from dimensional gradient structure and matched electrolyte of CoSe2@CNTs-MXene hold great application potential for stable sodium storage.
基金Key Research and Development Project of Anhui Province of China,Grant/Award Number:2023t07020005Anhui Innovation and Entrepreneurship Support Plan for Returned Overseas Students,Grant/Award Number:2022LCX018+2 种基金National Natural Science Foundation of China,Grant/Award Number:U1632151Open Project of Jiangsu Key Laboratory for Carbon‐Based Functional Materials&Devices,Grant/Award Number:KJS1802Natural Science Foundation of Anhui Province,China,Grant/Award Number:2308085QE137。
文摘Low efficiency and spectral instability caused by the surface defects have been considerable issues for the mixed-halogen blue emitting perovskite quantum dots light-emitting diodes(PeQLEDs).Here,an in situ surface passivation to perovskite quantum dots(PeQDs)is realized by introducing the metal cations competitive lattice occupancy assisted with acid-etching,in which the longchain,insulating and weakly bond surface ligands are removed by addition of octanoic acid(OTAC).Meanwhile,the dissolved A-site cations(Na^(+))compete with the protonated oleyl amine and are subsequently anchored to the surface vacancies.The preadded lead bromide,acting as inorganic ligands,demonstrates strong bonding to the uncoordinated surface ions.The as-synthesized PeQDs show the boosted photoluminescence quantum yield(PLQY)and superior stability with longer lifetime.As a result,the PeQLEDs(470 nm)based on the OTAC-Na PeQDs exhibit an external quantum efficiency of 8.42%in the mixed halogen PeQDs(CsPb(Br_(x)Cl_(1−x))_(3)).Moreover,the device exhibits superior spectra stability with negligible shift.Our competition mechanism in combination with in situ passivation strategy paves a new way for improving the performance of blue PeQLEDs.
