Ammonium-ion hybrid supercapacitors(A-HSCs)have emerged as promising candidates for next-generation energy storage owing to their inherent safety and environmental sustainability.Hexagonal tungsten oxide(h-WO_(3)),wit...Ammonium-ion hybrid supercapacitors(A-HSCs)have emerged as promising candidates for next-generation energy storage owing to their inherent safety and environmental sustainability.Hexagonal tungsten oxide(h-WO_(3)),with its well-defined tunnel structure,holds great promise as a negative electrode material for NH^(4+)storage.However,its practical application is hindered by structural instability and poor intrinsic electrical conductivity.To address these challenges,a dual-regulation strategy is proposed,integrating molybdenum(Mo)doping and NH^(4+)pre-intercalation to concurrently optimize the tunnel structure and electronic environment of h-WO_(3)(Mo-NWO).Comprehensive experimental and theoretical analyses reveal that Mo doping narrows the bandgap of WO_(3)and reduces the diffusion energy barrier,thereby accelerating NH^(4+)adsorption and diffusion.Simultaneously,NH^(4+)pre-intercalation stabilizes the tunnel framework via hydrogen bonding,ensuring structural reversibility.As expected,the Mo-NWO/AC electrode achieves a high areal capacitance of 13.6 F cm^(−2)at 5 mA cm^(−2)and retains 80.14%of its capacitance after 5000 cycles,demonstrating exceptional rate capability and cycling stability.Moreover,the assembled Mn_(3)O_(4)//Mo-NWO/AC device delivers a high energy density of 3.41 mWh cm^(−2)and outstanding long-term stability(85.75%retention after 12,000 cycles).This work provides a viable strategy for designing high-performance NH^(4+)storage materials and advances the development of sustainable energy storage systems.展开更多
Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible s...Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering.展开更多
The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries.To address this,a dopamine-intercalated WS_(2) hybrid(Dam-WS1.87)with a unique strain-self-relaxation archit...The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries.To address this,a dopamine-intercalated WS_(2) hybrid(Dam-WS1.87)with a unique strain-self-relaxation architecture was fabricated.Interestingly,the WS_(2) matrix undergoes a structural transformation owing to the intense infiltration effect of dopamine molecules,expanding interlayer spacing(0.813 nm)and introducing 6.5%S-vacancies while preserving high compaction density(4.0874 gcm^(-3)).The engineered structure demonstrates remarkable mechanical stability,exhibiting only 19.0%crystallite expansion upon full potassiation(vs.101.3%for pristine WS_(2)),demonstrating efficient strain alleviation through its strain-self-relaxation architecture.As a result,Dam-WS1.87delivers reversible capacities of 312.6 m A h g^(-1)/1277.7 mA h cm^(-3)at 0.125 C,along with superior rate capability(maintaining 210.4 m A h g^(-1)at 5 C)and unprecedented cycling stability(85.3%capacity retention after 1400 cycles at 1 C).This work provides new insights into designing strain-tolerant electrode materials for nextgeneration energy storage systems.展开更多
Protons emerge as superior charge carriers due to the lowest mass-to-charge ratio,ultra-high natural abundance,and the smallest ionic radius.Herein,2.0 M H_(2) SO_(4) dissolved in EG(ethylene glycol)/H_(2)O cosolvent ...Protons emerge as superior charge carriers due to the lowest mass-to-charge ratio,ultra-high natural abundance,and the smallest ionic radius.Herein,2.0 M H_(2) SO_(4) dissolved in EG(ethylene glycol)/H_(2)O cosolvent is investigated as an aqueous proton battery electrolyte,which not only enhances the cycling performance of MoO_(3) nanorod anode but also improves its low-temperature electrochemical performance.Specifically,the EG tightly adsorbs onto the surface of MoO_(3) nanorods,thereby inhibiting the corrosion from H_(2)O molecules in the electrolyte and suppressing the dissolution of MoO_(3).In addition,EG molecule disturbs the hydrogen-bond network between H_(2)O molecules,which greatly decreases the freezing point of the electrolyte,endowing the MoO_(3) nanorods with excellent low-temperature electrochemical performance.Therefore,the MoO_(3) nanorods exhibit a capacity retention of 96.9%after 2000 cycles at a current density of 10 A g^(-1)in a three-electrode system.After assembling with CuHCF cathode,under-40℃,the full battery displays negligible capacity decay for over 2500 cycles at 1 A g^(-1).These results indicate that the cosolvent strategy has the promising potential in enhancing the performance of aqueous proton batteries.展开更多
MoTe_(2) has emerged as a promising candidate in the field of integrated circuits,memristive devices,and catalysts,owing to its polymorphic nature across different phases.Experimentally,strain engineering has been dem...MoTe_(2) has emerged as a promising candidate in the field of integrated circuits,memristive devices,and catalysts,owing to its polymorphic nature across different phases.Experimentally,strain engineering has been demonstrated as an effective approach for manipulating the phase transition of MoTe_(2),but the mechanism remains unclear.The strain-dependent phase transition and its micro-mechanisms have been investigated based on first principle calculations.As demonstrated,critical strain and phase transition path from H→T'phases are strongly governed by the applied strain's orientation,magnitude,and triaxiality.At the atomic level,nonzero movements of Te atoms within the phase transition domain with mechanical unloading have been clarified,together with an advanced understanding on the impact of strain on Te-vacancies migration.These insights advanced the knowledge of MoTe_(2) phase transition behavior and demonstrated the large space to explore potential applications through strain,defect,and phase engineering.展开更多
When stacking two-dimensional(2D)materials with a lattice mismatch and/or a small twist,moirésuperlattice emerges with fascinating electronic and optical properties.The fabrication of such stacked 2D materials us...When stacking two-dimensional(2D)materials with a lattice mismatch and/or a small twist,moirésuperlattice emerges with fascinating electronic and optical properties.The fabrication of such stacked 2D materials usually requires multiple transfer and stack processes,assisted by a certain transfer medium which needs to be removed afterwards,and it is very challenging to maintain pristine and clean surfaces/interfaces for these stacked structures.In this work,we report a facile direct bonding method for fabrication of twisted MoS_(2) bilayers with ultra-clean surfaces/interfaces.Novel interlayer interactions are revealed in the as-fabricated high-quality samples,leading to twist-angle related dispersion behavior of various Raman modes,such as layer breathing modes,shear modes and E_(2g)modes,as well as indirect bandgap excitons.Field-effect transistors(FETs)of twisted MoS_(2) bilayers also exhibit angle-dependent performance,which could be attributed to the band structure evolution.This facile method holds significance for the future integration of pre-designed multilayer 2D materials and paves a way to explore underlying physical mechanisms and potential applications.展开更多
基金supported by the National Natural Science Foundation of Guangxi Province(2024GXNSFBA010033)the Special Fund for Science and Technology Development of Guangxi(Grant No.AD25069078).
文摘Ammonium-ion hybrid supercapacitors(A-HSCs)have emerged as promising candidates for next-generation energy storage owing to their inherent safety and environmental sustainability.Hexagonal tungsten oxide(h-WO_(3)),with its well-defined tunnel structure,holds great promise as a negative electrode material for NH^(4+)storage.However,its practical application is hindered by structural instability and poor intrinsic electrical conductivity.To address these challenges,a dual-regulation strategy is proposed,integrating molybdenum(Mo)doping and NH^(4+)pre-intercalation to concurrently optimize the tunnel structure and electronic environment of h-WO_(3)(Mo-NWO).Comprehensive experimental and theoretical analyses reveal that Mo doping narrows the bandgap of WO_(3)and reduces the diffusion energy barrier,thereby accelerating NH^(4+)adsorption and diffusion.Simultaneously,NH^(4+)pre-intercalation stabilizes the tunnel framework via hydrogen bonding,ensuring structural reversibility.As expected,the Mo-NWO/AC electrode achieves a high areal capacitance of 13.6 F cm^(−2)at 5 mA cm^(−2)and retains 80.14%of its capacitance after 5000 cycles,demonstrating exceptional rate capability and cycling stability.Moreover,the assembled Mn_(3)O_(4)//Mo-NWO/AC device delivers a high energy density of 3.41 mWh cm^(−2)and outstanding long-term stability(85.75%retention after 12,000 cycles).This work provides a viable strategy for designing high-performance NH^(4+)storage materials and advances the development of sustainable energy storage systems.
基金financially supported by the supported by Shandong Provincial Natural Science Foundation(ZR2024MB108)Taishan Young Scholar Program(tsqn202312312)Excellent Young Scholars of the Shandong Provincial Natural Science Foundation(Overseas)(2023HWYQ-112)。
文摘Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering.
基金financially supported by the National Natural Science Foundation of China(22578493,22238012,52270115)the Beijing Nova Program(20240484570)+4 种基金the Postdoctoral Fellowship Program of CPSF(2024GZB20240847)the China Postdoctoral Science Foundation(M753609)the CNPC Innovation Found(2024DQ02-0206,2022DQ02-0410)the Science Foundation of China University of Petroleum(Beijing)(2462023QNXZ015,2462024PTJS011)the Open Project Fund of the Ministry of Education Engineering Research Center for Clean Low Carbon Energy(ZX20240167)。
文摘The structural stress/strain induced by K-ion intercalation remains a critical challenge for K-ion batteries.To address this,a dopamine-intercalated WS_(2) hybrid(Dam-WS1.87)with a unique strain-self-relaxation architecture was fabricated.Interestingly,the WS_(2) matrix undergoes a structural transformation owing to the intense infiltration effect of dopamine molecules,expanding interlayer spacing(0.813 nm)and introducing 6.5%S-vacancies while preserving high compaction density(4.0874 gcm^(-3)).The engineered structure demonstrates remarkable mechanical stability,exhibiting only 19.0%crystallite expansion upon full potassiation(vs.101.3%for pristine WS_(2)),demonstrating efficient strain alleviation through its strain-self-relaxation architecture.As a result,Dam-WS1.87delivers reversible capacities of 312.6 m A h g^(-1)/1277.7 mA h cm^(-3)at 0.125 C,along with superior rate capability(maintaining 210.4 m A h g^(-1)at 5 C)and unprecedented cycling stability(85.3%capacity retention after 1400 cycles at 1 C).This work provides new insights into designing strain-tolerant electrode materials for nextgeneration energy storage systems.
基金supported by the National Natural Science Foundation of China(22409071)Natural Foundation of Shandong Province(ZR2024QB120)+2 种基金Youth Innovation Group Plan of Shandong Province(2024KJG046)Higher-Level Talent Initial Scientific Research and Discipline Construction Fund(511/1009530)Joint Funds of the National Natural Science Foundation of China(No.U22A20140)。
文摘Protons emerge as superior charge carriers due to the lowest mass-to-charge ratio,ultra-high natural abundance,and the smallest ionic radius.Herein,2.0 M H_(2) SO_(4) dissolved in EG(ethylene glycol)/H_(2)O cosolvent is investigated as an aqueous proton battery electrolyte,which not only enhances the cycling performance of MoO_(3) nanorod anode but also improves its low-temperature electrochemical performance.Specifically,the EG tightly adsorbs onto the surface of MoO_(3) nanorods,thereby inhibiting the corrosion from H_(2)O molecules in the electrolyte and suppressing the dissolution of MoO_(3).In addition,EG molecule disturbs the hydrogen-bond network between H_(2)O molecules,which greatly decreases the freezing point of the electrolyte,endowing the MoO_(3) nanorods with excellent low-temperature electrochemical performance.Therefore,the MoO_(3) nanorods exhibit a capacity retention of 96.9%after 2000 cycles at a current density of 10 A g^(-1)in a three-electrode system.After assembling with CuHCF cathode,under-40℃,the full battery displays negligible capacity decay for over 2500 cycles at 1 A g^(-1).These results indicate that the cosolvent strategy has the promising potential in enhancing the performance of aqueous proton batteries.
基金supported by NSFC Grants(Nos.12032004,11872114,and 11502150)Natural Science Foundation of Hebei Province of China(No.A2016210060)+1 种基金The Higher Education Youth Talents Program of Hebei Province of China(No.BJ2017052)Science and Technology Project of Hebei Education Department(No.QN2020204)。
文摘MoTe_(2) has emerged as a promising candidate in the field of integrated circuits,memristive devices,and catalysts,owing to its polymorphic nature across different phases.Experimentally,strain engineering has been demonstrated as an effective approach for manipulating the phase transition of MoTe_(2),but the mechanism remains unclear.The strain-dependent phase transition and its micro-mechanisms have been investigated based on first principle calculations.As demonstrated,critical strain and phase transition path from H→T'phases are strongly governed by the applied strain's orientation,magnitude,and triaxiality.At the atomic level,nonzero movements of Te atoms within the phase transition domain with mechanical unloading have been clarified,together with an advanced understanding on the impact of strain on Te-vacancies migration.These insights advanced the knowledge of MoTe_(2) phase transition behavior and demonstrated the large space to explore potential applications through strain,defect,and phase engineering.
基金supported by Guangdong Major Project of Basic and Applied Basic Research(Grant No.2021B0301030002)the National Key Research and Development Program(Grant No.2021YFA1202900)the National Natural Science Foundation of China(Grant Nos.62204166 and 62404145)。
文摘When stacking two-dimensional(2D)materials with a lattice mismatch and/or a small twist,moirésuperlattice emerges with fascinating electronic and optical properties.The fabrication of such stacked 2D materials usually requires multiple transfer and stack processes,assisted by a certain transfer medium which needs to be removed afterwards,and it is very challenging to maintain pristine and clean surfaces/interfaces for these stacked structures.In this work,we report a facile direct bonding method for fabrication of twisted MoS_(2) bilayers with ultra-clean surfaces/interfaces.Novel interlayer interactions are revealed in the as-fabricated high-quality samples,leading to twist-angle related dispersion behavior of various Raman modes,such as layer breathing modes,shear modes and E_(2g)modes,as well as indirect bandgap excitons.Field-effect transistors(FETs)of twisted MoS_(2) bilayers also exhibit angle-dependent performance,which could be attributed to the band structure evolution.This facile method holds significance for the future integration of pre-designed multilayer 2D materials and paves a way to explore underlying physical mechanisms and potential applications.
