Nickel-based cathodes in aqueous nickel-zinc batteries typically suffer from sluggish reaction kinetics and limited energy density.In situ introduction of metal phosphides and rational construction of heterostructures...Nickel-based cathodes in aqueous nickel-zinc batteries typically suffer from sluggish reaction kinetics and limited energy density.In situ introduction of metal phosphides and rational construction of heterostructures can effectively promote electron/ion transport.However,the complex evolution of phosphidation and intractable phosphidizing degree greatly affect the composition of active phase,active sites,charge transfer rate,and ion adsorption strength of cathodes.Herein,the critical bimetallic phosphide layer(CBPL)is constructed on the NiCo-layered double hydroxide(NiCo-LDH)skeleton by a controllable anion-exchange strategy,yielding a novel nanohybrid cathode(NiCo-P1.0,1.0 representing the mass ratio of Na_(2)H_(2)PO_(2)to NiCo-LDH).The high-conductivity CBPL with the inner NiCo-LDH forms extensive heterostructures,effectively regulating the electronic structure via charge transfer,thereby improving electrical conductivity.Remarkably,the CBPL exhibits unexpected electrochemical activity and synergizes with NiCo-LDH for electrode reactions,ultimately delivering extra energy.Benefiting from the bifunctional CBPL,NiCo-P1.0 delivers an optimal capacity of 286.64 mAh g^(−1)at 1C(1C=289 mAh g^(−1))and superb rate performance(a capacity retention of 72.22%at 40C).The assembled NiCo-P1.0//Zn battery achieves ultrahigh energy/power density(503.62 Wh kg^(−1)/18.62 kW kg^(−1),based on the mass loading of active material on the cathode),and the flexible quasi-solid-state pouch cell validates its practicality.This work demonstrates the superiority of bifunctional CBPL for surface modification,providing an effective and scalable compositing strategy in achieving high-performance cathodes for aqueous batteries.展开更多
Commercial carbon clothes have the potential to be utilized as supercapacitor electrodes due to their low cost and high conductivity.However,the negligible surface area of the carbon clothes serves as a serious impedi...Commercial carbon clothes have the potential to be utilized as supercapacitor electrodes due to their low cost and high conductivity.However,the negligible surface area of the carbon clothes serves as a serious impediment to their utilization.Herein,we report a facile calcination activation method for carbon cloths to realize remarkable comprehensive electrochemical performance.The activated carbon cloths deliver a high areal capacitance(1700 mF/cm^2),good rate capability,and stable cycling performance up to 20,000 cycles.Owing to the stability in the wide potential window,a designed symmetric capacitor can function in a cell voltage of 2.0 V and delivers high volumetric and gravimetric energy densities of 7.62 mWh/cm^3 and 18.2 Wh/kg,respectively.The remarkable electrochemical performance is attributed to rich microporosity with high surface area,superior electrolyte wettability,and stability in wide potential window.展开更多
As a promising candidate for next generation energy storage devices, lithium sulfur (Li-S) batteries still confrant rapid capacity degradation and low rate capability. Herein, we report a well-architected porous nitro...As a promising candidate for next generation energy storage devices, lithium sulfur (Li-S) batteries still confrant rapid capacity degradation and low rate capability. Herein, we report a well-architected porous nitrogen-doped carbon/MnO coaxial nanotubes (MnO@PNC) as an efficient sulfur host material. The host shows excellent electron conductivity, sufficient ion transport channels and strong adsorption capability for the polysulfides, resulting from the abundant nitrogen-doped sites and pores as well as MnO in the carbon shell of MnO@PNC. The MnO@PNC-S composite electrode with a sulfur content of 75 wt.% deliveries a specific capacity of 802 mAh·g^-1 at a high rate of 5.0C and outstanding cycling stability with a capacity retention of 82% after 520 cycles at 1.0C.展开更多
基金supported by the National Natural Science Foundation of China(No.52373249,W2433146)the Science and Technology Project of Yibin Sanjiang New Area(No.2023SJXQSXZJ003)the Fundamental Research Funds for the Central Universities(No.20822041F4045).
文摘Nickel-based cathodes in aqueous nickel-zinc batteries typically suffer from sluggish reaction kinetics and limited energy density.In situ introduction of metal phosphides and rational construction of heterostructures can effectively promote electron/ion transport.However,the complex evolution of phosphidation and intractable phosphidizing degree greatly affect the composition of active phase,active sites,charge transfer rate,and ion adsorption strength of cathodes.Herein,the critical bimetallic phosphide layer(CBPL)is constructed on the NiCo-layered double hydroxide(NiCo-LDH)skeleton by a controllable anion-exchange strategy,yielding a novel nanohybrid cathode(NiCo-P1.0,1.0 representing the mass ratio of Na_(2)H_(2)PO_(2)to NiCo-LDH).The high-conductivity CBPL with the inner NiCo-LDH forms extensive heterostructures,effectively regulating the electronic structure via charge transfer,thereby improving electrical conductivity.Remarkably,the CBPL exhibits unexpected electrochemical activity and synergizes with NiCo-LDH for electrode reactions,ultimately delivering extra energy.Benefiting from the bifunctional CBPL,NiCo-P1.0 delivers an optimal capacity of 286.64 mAh g^(−1)at 1C(1C=289 mAh g^(−1))and superb rate performance(a capacity retention of 72.22%at 40C).The assembled NiCo-P1.0//Zn battery achieves ultrahigh energy/power density(503.62 Wh kg^(−1)/18.62 kW kg^(−1),based on the mass loading of active material on the cathode),and the flexible quasi-solid-state pouch cell validates its practicality.This work demonstrates the superiority of bifunctional CBPL for surface modification,providing an effective and scalable compositing strategy in achieving high-performance cathodes for aqueous batteries.
基金supported by the National Natural Science Fund for Distinguished Young Scholars(No.51425204)the National Natural Science Foundation of China(No.51521001)+2 种基金the National Key Research and Development Program of China(No.2016YFA0202603)the Programme of Introducing Talents of Discipline to Universities(No.B17034)the Yellow Crane Talent(Science&Technology)Program of Wuhan City。
文摘Commercial carbon clothes have the potential to be utilized as supercapacitor electrodes due to their low cost and high conductivity.However,the negligible surface area of the carbon clothes serves as a serious impediment to their utilization.Herein,we report a facile calcination activation method for carbon cloths to realize remarkable comprehensive electrochemical performance.The activated carbon cloths deliver a high areal capacitance(1700 mF/cm^2),good rate capability,and stable cycling performance up to 20,000 cycles.Owing to the stability in the wide potential window,a designed symmetric capacitor can function in a cell voltage of 2.0 V and delivers high volumetric and gravimetric energy densities of 7.62 mWh/cm^3 and 18.2 Wh/kg,respectively.The remarkable electrochemical performance is attributed to rich microporosity with high surface area,superior electrolyte wettability,and stability in wide potential window.
基金the National Natural Science Fund for Distinguished Young Scholars (No. 51425204)the National Natural Science Foundation of China (Nos. 51521001 and 51702247)+2 种基金the National Key Research and Development Program of China (No. 2016YFA0202603)the Programme of Introducing Talents of Discipline to Universities (No. B17034)the Fundamental Research Funds for the Central Universities (WUT: 2016111001, 2017111009, 2017111005, 2017111030).
文摘As a promising candidate for next generation energy storage devices, lithium sulfur (Li-S) batteries still confrant rapid capacity degradation and low rate capability. Herein, we report a well-architected porous nitrogen-doped carbon/MnO coaxial nanotubes (MnO@PNC) as an efficient sulfur host material. The host shows excellent electron conductivity, sufficient ion transport channels and strong adsorption capability for the polysulfides, resulting from the abundant nitrogen-doped sites and pores as well as MnO in the carbon shell of MnO@PNC. The MnO@PNC-S composite electrode with a sulfur content of 75 wt.% deliveries a specific capacity of 802 mAh·g^-1 at a high rate of 5.0C and outstanding cycling stability with a capacity retention of 82% after 520 cycles at 1.0C.
