Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes u...Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes upon storing in a humid atmosphere.In response to these issues,we have designed an oxide with co-doping of Cu and Al which can balance both cost and structural stability.The redox reaction of Cu^(2+/3+)can provide certain charge compensation,and the introduction of Al can further suppress the Jahn-Teller effect of Mn,thereby achieving superior long-term cycling performance.The ex-situ XRD testing indicates that Cu/Al co-doping can effectively suppress the phase transition of P2-O2 at high voltage,thereby explaining the improvement in electrochemical performance.DFT calculations reveal a high chemical tolerance to moisture,with lower adsorption energy for H_(2)O compared to pure Na_(0.67)Cu_(0.25)Mn_(0.75)O_(2).A representative Na_(0.67)Cu_(0.20)Al_(0.05)Mn_(0.75)O_(2)cathode demonstrates impressive reversible capacities of 148.7 mAh/g at 0.2 C,along with a remarkable capacity retention of 79.1%(2 C,500 cycles).展开更多
Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cath...Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cathodes with long-term cycling stability poses challenges,stemming from irreversible phase transitions,structural degradation,and lattice oxygen instability during electrochemical cycling.Here,we propose a one-step NbB_(2)modification strategy that enhances both bulk and surface properties of Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes.By exploiting different techniques,we disclose that bulk Nb and B doping combined with a Nb-Transition Metal-BO_(3)surface layer reconstruction enable a reversible P2-OP4 phase transition and,meanwhile,improve anionic redox reversibility.In addition,Li^(+)migrates into alkali-metal layers and underpins the layered structure through the“pillar effect”,thereby facilitating the Na^(+)diffusion in Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes and retaining their structural integrity at high voltage.As a result,the modified cathodes achieve 93.6%capacity retention after 500 cycles at 1C and deliver specific capacities above 114 m A h g^(-1)at 10C within 2.0-4.3 V.Contrary to the previous studies reporting that OP4 phase are detrimental to the structural stability of layered cathodes,we experimentally validate that a well-regulated P2-OP4 phase transition is beneficial for structural and electrochemical stabilities.展开更多
Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable...Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.展开更多
目的探讨细胞S相激酶相关蛋白(S-phasekinase associated protein 2,Skp2)、p27蛋白与喉鳞状细胞癌(简称喉癌)各临床因素及预后的相关性。方法采用免疫组化SP法检测79例喉癌患者肿瘤组织的Skp2、p27表达。结果喉癌中Skp2高表达率(53.16%...目的探讨细胞S相激酶相关蛋白(S-phasekinase associated protein 2,Skp2)、p27蛋白与喉鳞状细胞癌(简称喉癌)各临床因素及预后的相关性。方法采用免疫组化SP法检测79例喉癌患者肿瘤组织的Skp2、p27表达。结果喉癌中Skp2高表达率(53.16%)显著高于正常喉组织(0%,P<0.05);喉癌Skp2蛋白低表达组的5年生存率(72.18%)显著高于高表达组(44.17%,P<0.01)。p27蛋白在喉癌和癌旁喉组织中的高表达率分别为30.38%和90%,差异具有显著性(P<0.05);喉癌p27蛋白高表达组的5年生存率(72.98%)显著高于低表达组(51.13%,P<0.01)。将Skp2和p27结合分析,Skp2高表达并p27低表达组的5年生存率最低,与另一组相比具有显著性差异(P=0.001)。结论Skp2蛋白通过降解靶蛋白p27可能在喉癌发生、发展中发挥重要作用。展开更多
Sodium ion capacitors(SICs) have been considered as a kind of promising devices to achieve both high power and energy density. However, it is still a challenge to achieve high energy output at elevated power delivery ...Sodium ion capacitors(SICs) have been considered as a kind of promising devices to achieve both high power and energy density. However, it is still a challenge to achieve high energy output at elevated power delivery due to the poor rate capability of battery-type electrode materials and the kinetic mismatch with capacitor-type electrode materials. In this work, to fabricate SICs, P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2(P2-NCM)was chosen as the battery-type cathode material, and a typical metal-organic framework(MOF) material,zeolitic imidazolate framework-8(ZIF-8) derived carbon(ZDC) was utilized as the capacitor-type anode material. Due to the kinetic match and high-rate performance of both electrodes, the ZDC//P2-NCM SICs exhibited an energy output of 18.8 Wh kg^(-1) at a high power delivery of 12.75 kW kg^(-1).展开更多
Charging P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)to 4.5 V for higher capacity is enticing.However,it leads to severe capacity fading,ascribing to the lattice oxygen evolution and the P2-O2 phase transformation.Here,the Mg Fe_...Charging P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)to 4.5 V for higher capacity is enticing.However,it leads to severe capacity fading,ascribing to the lattice oxygen evolution and the P2-O2 phase transformation.Here,the Mg Fe_(2)O_(4) coating and Mg,Fe co-doping were constructed simultaneously by Mg,Fe surface treatment to suppress lattice oxygen evolution and P2-O2 phase transformation of P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)at deep charging.Through ex-situ X-ray diffraction(XRD)tests,we found that the Mg,Fe bulk co-doping could reduce the repulsion between transition metals and Na+/vacancies ordering,thus inhibiting the P2-O2 phase transition and significantly reducing the irreversible volume change of the material.Meanwhile,the internal electric field formed by the dielectric polarization of Mg Fe_(2)O_(4) effectively inhibits the outward migration of oxidized O^(a-)(a<2),thereby suppressing the lattice oxygen evolution at deep charging,confirmed by in situ Raman and ex situ XPS techniques.P2-Na NM@MF-3 shows enhanced high-voltage cycling performance with capacity retentions of 84.8% and 81.3%at 0.1 and 1 C after cycles.This work sheds light on regulating the surface chemistry for Na-layered oxide materials to enhance the high-voltage performance of Na-ion batteries.展开更多
P2-type layered Ni–Mn-based oxides are vital cathode materials for sodiumion batteries(SIBs)due to their high discharge capacity and working voltage.However,they suffer from the detrimental P2→O_(2) phase transition...P2-type layered Ni–Mn-based oxides are vital cathode materials for sodiumion batteries(SIBs)due to their high discharge capacity and working voltage.However,they suffer from the detrimental P2→O_(2) phase transition induced by the O^(2-)−O^(2-)−electrostatic repulsion upon high-voltage charge,which leads to rapid capacity fade.Herein,we construct a P2-type Ni–Mn-based layered oxide cathode with a core-shell structure(labeled as NM–Mg–CS).The P2-Na_(0.67)[Ni_(0.25)Mn_(0.75)]O_(2)(NM)core is enclosed by the robust P2-Na_(0.67)[Ni_(0.21)Mn_(0.71)Mg_(0.08)]O_(2)(NM–Mg)shell.The NM–Mg–CS exhibits the phase-transition-free character with mitigated volume change because the confinement effect of shell is conductive to inhibit the irreversible phase transition of the core material.As a result,it drives a high capacity retention of 81%after 1000 cycles at 5 C with an initial capacity of 78mA h/g.And the full cell with the NM–Mg–CS cathode and hard carbon anode delivers stable capacities over 250 cycles.The successful construction of the core-shell structure in P2-type layered oxides sheds light on the development of high-capacity and long-life cathode materials for SIBs.展开更多
Sodium-ion intercalation oxides generally possess high compositional diversity according to their different stacking sequences.The sodium diffusion pathway in layered P-type materials used in sodium-ion batteries is o...Sodium-ion intercalation oxides generally possess high compositional diversity according to their different stacking sequences.The sodium diffusion pathway in layered P-type materials used in sodium-ion batteries is open,which can increase their rate capability by directly transmitting Na+between adjacent triangular prismatic channels,rather than passing through an intermediate tetrahedral site in O-type structure.However,how the structure chemistry of the P-type oxides determines their electrochemical properties has not been fully understood yet.Herein,by comparing the crystalline structures,electrochemical behaviors,ion/electron transport dynamics of a couple of P-type intercalation cathodes,P2-Na_(2/3)Ni1/3Mn_(2/3)O_(2)and P3-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)with the same compositions,we demonstrate experimentally and computationally that the P2 phase delivers better cycling stability and rate capability than the P3 counterpart due to the predominant contribution of the faster intrinsic Na diffusion kinetics in the P2 bulk.We also point out that it is the electronic conductivity that captures the key electrochemistry of layered P3-type materials and makes them possible to enhance the sodium storage performance.The results reveal that the correlation between stacking structure and functional properties in two typical layered P-type cathodes,providing new guidelines for preparing and designing alkali-metal layered oxide materials with improved battery performance.展开更多
基金supported by National Natural Science Youth Foundation of China(No.22308294)National Natural Science Foundation of China(No.22179077)+1 种基金Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.SJCX23_1868)Qing Lan Project of Jiangsu University and the Funding for school-level research projects of Yancheng Institute of Technology.
文摘Mn-based P2-type oxides are considered as promising cathodes for Na-ion batteries;however,they face significant challenges,including structural degradation when charged at high cutoff voltages and structural changes upon storing in a humid atmosphere.In response to these issues,we have designed an oxide with co-doping of Cu and Al which can balance both cost and structural stability.The redox reaction of Cu^(2+/3+)can provide certain charge compensation,and the introduction of Al can further suppress the Jahn-Teller effect of Mn,thereby achieving superior long-term cycling performance.The ex-situ XRD testing indicates that Cu/Al co-doping can effectively suppress the phase transition of P2-O2 at high voltage,thereby explaining the improvement in electrochemical performance.DFT calculations reveal a high chemical tolerance to moisture,with lower adsorption energy for H_(2)O compared to pure Na_(0.67)Cu_(0.25)Mn_(0.75)O_(2).A representative Na_(0.67)Cu_(0.20)Al_(0.05)Mn_(0.75)O_(2)cathode demonstrates impressive reversible capacities of 148.7 mAh/g at 0.2 C,along with a remarkable capacity retention of 79.1%(2 C,500 cycles).
基金financially supported by the National Key R&D Program of China(2020YFA0406203)National Natural Science Foundation of China(92472115,52371225 and 52072008)+5 种基金Guangdong Basic and Applied Basic Research Foundation(2022B1515120070,2022A1515110816 and 2022A1515110596)the Large Scientific Facility Open Subject of Songshan Lake,Dongguan,Guangdong(KFKT2022A04)Jialin Xie Fund(E4546IU2)the open research fund of Songshan Lake Materials Laboratory(2023SLABFN02)The Major Science and Technology Infrastructure Project of Material Genome Big-science Facilities Platform supported by the Municipal Development and Reform Commission of Shenzhen also contributed to this researchthe allocation of beamtime at BL15U and BL02B02 beamlines at SSRF。
文摘Sodium-ion batteries have been deemed as a sustainable alternative to lithium-ion systems due to the abundance and affordability of sodium sources.Nevertheless,developing high-energy-density P2-type layered oxide cathodes with long-term cycling stability poses challenges,stemming from irreversible phase transitions,structural degradation,and lattice oxygen instability during electrochemical cycling.Here,we propose a one-step NbB_(2)modification strategy that enhances both bulk and surface properties of Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes.By exploiting different techniques,we disclose that bulk Nb and B doping combined with a Nb-Transition Metal-BO_(3)surface layer reconstruction enable a reversible P2-OP4 phase transition and,meanwhile,improve anionic redox reversibility.In addition,Li^(+)migrates into alkali-metal layers and underpins the layered structure through the“pillar effect”,thereby facilitating the Na^(+)diffusion in Na_(0.8)Li_(0.12)Ni_(0.22)Mn_(0.66)O_(2)cathodes and retaining their structural integrity at high voltage.As a result,the modified cathodes achieve 93.6%capacity retention after 500 cycles at 1C and deliver specific capacities above 114 m A h g^(-1)at 10C within 2.0-4.3 V.Contrary to the previous studies reporting that OP4 phase are detrimental to the structural stability of layered cathodes,we experimentally validate that a well-regulated P2-OP4 phase transition is beneficial for structural and electrochemical stabilities.
基金financially supported by the National Natural Science Foundation of China(12175089,12205127,52220105010)the Key Research and Development Program of Yunnan Province(202103AF140006)+3 种基金the Applied Basic Research Programs of Yunnan Provincial Science and Technology Department(202001AW070004,202301AS070051,202301AU070064)Yunnan Industrial Innovative Talents Program for“Xingdian Talent Support Plan”(KKXY202252001)Yunnan Program for Introducing Foreign Talents(202305AO350042)Yunnan Major Scientific and Technological Projects(202202AG050003).
文摘Sodium-ion batteries(SIBs)are emerging as a promising alternative for large-scale energy storage,particularly in grid applications.Within the array of potential cathode materials,Fe/Mn-based layered oxides are notable for their advantageous theoretical specific capacity,economic viability,and environmental sustainability.Nevertheless,the practical application of Fe/Mn-based layered oxides is constrained by their suboptimal cycle performance and rate capability during actual charging and discharging.Ion doping is an effective approach for addressing the aforementioned issues.In this context,we have successfully developed a novel K^(+) and Mg^(2+) codoped P2-Na_(0.7)Fe_(0.5)Mn_(0.5)O_(2) cathode to address these challenges.By doping with 0.05 K^(+) and 0.2 Mg^(2+),the cathode demonstrated excellent cycling stability,retaining 95% of its capacity after 50 cycles at 0.2C,whereas the undoped material retained only 59.7%.Even within a wider voltage range,the co-doped cathode retained 88% of its capacity after 100 cycles at 1C.This work integrated Mg^(2+) to activate oxygen redox reactions in Fe/Mn-based layered cathodes,thereby promoting a reversible hybrid redox process involving both anions and cations.Building on the Mg doping,larger K^(+) ions were introduced into the edge-sharing Na^(+) sites,enhancing the material's cyclic stability and expanding the interplanar distance.The significant improvement of Na^(+) diffusion coefficient by K^(+)/Mg^(2+) co-doping has been further confirmed via the galvanostatic intermittent titration technique(GITT).The study emphasizes the importance of co-doping with different coordination environments in future material design,aiming to achieve high operating voltage and energy density.
文摘目的探讨细胞S相激酶相关蛋白(S-phasekinase associated protein 2,Skp2)、p27蛋白与喉鳞状细胞癌(简称喉癌)各临床因素及预后的相关性。方法采用免疫组化SP法检测79例喉癌患者肿瘤组织的Skp2、p27表达。结果喉癌中Skp2高表达率(53.16%)显著高于正常喉组织(0%,P<0.05);喉癌Skp2蛋白低表达组的5年生存率(72.18%)显著高于高表达组(44.17%,P<0.01)。p27蛋白在喉癌和癌旁喉组织中的高表达率分别为30.38%和90%,差异具有显著性(P<0.05);喉癌p27蛋白高表达组的5年生存率(72.98%)显著高于低表达组(51.13%,P<0.01)。将Skp2和p27结合分析,Skp2高表达并p27低表达组的5年生存率最低,与另一组相比具有显著性差异(P=0.001)。结论Skp2蛋白通过降解靶蛋白p27可能在喉癌发生、发展中发挥重要作用。
基金supported by Tianjin Municipal Science and Technology Commission (16PTSYJC00010 and 17JCZDJC37100)the National Natural Science Foundation of China (21773126)
文摘Sodium ion capacitors(SICs) have been considered as a kind of promising devices to achieve both high power and energy density. However, it is still a challenge to achieve high energy output at elevated power delivery due to the poor rate capability of battery-type electrode materials and the kinetic mismatch with capacitor-type electrode materials. In this work, to fabricate SICs, P2-Na_(0.67)Co_(0.5)Mn_(0.5)O_2(P2-NCM)was chosen as the battery-type cathode material, and a typical metal-organic framework(MOF) material,zeolitic imidazolate framework-8(ZIF-8) derived carbon(ZDC) was utilized as the capacitor-type anode material. Due to the kinetic match and high-rate performance of both electrodes, the ZDC//P2-NCM SICs exhibited an energy output of 18.8 Wh kg^(-1) at a high power delivery of 12.75 kW kg^(-1).
基金supported by the Special Project for the Central Government to Guide Local Technological Development (GUIKE ZY20198008)the Guangxi Technology Base and talent Subject (GUIKE AD20238012,AD20297086)+5 种基金the Natural Science Foundation of Guangxi Province (2021GXNSFDA075012)the National Natural Science Foundation of China (51902108,52104298,22169004)the National Natural Science Foundation of China (U20A20249)the Regional Innovation and Development Joint Fundthe Guangxi Innovation Driven Development Subject (GUIKE AA19182020,19254004)the Special Fund for Guangxi Distinguished Expert。
文摘Charging P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)to 4.5 V for higher capacity is enticing.However,it leads to severe capacity fading,ascribing to the lattice oxygen evolution and the P2-O2 phase transformation.Here,the Mg Fe_(2)O_(4) coating and Mg,Fe co-doping were constructed simultaneously by Mg,Fe surface treatment to suppress lattice oxygen evolution and P2-O2 phase transformation of P2-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)at deep charging.Through ex-situ X-ray diffraction(XRD)tests,we found that the Mg,Fe bulk co-doping could reduce the repulsion between transition metals and Na+/vacancies ordering,thus inhibiting the P2-O2 phase transition and significantly reducing the irreversible volume change of the material.Meanwhile,the internal electric field formed by the dielectric polarization of Mg Fe_(2)O_(4) effectively inhibits the outward migration of oxidized O^(a-)(a<2),thereby suppressing the lattice oxygen evolution at deep charging,confirmed by in situ Raman and ex situ XPS techniques.P2-Na NM@MF-3 shows enhanced high-voltage cycling performance with capacity retentions of 84.8% and 81.3%at 0.1 and 1 C after cycles.This work sheds light on regulating the surface chemistry for Na-layered oxide materials to enhance the high-voltage performance of Na-ion batteries.
基金supported by the National Natural Science Foundation of China(Nos.22121005 and 52072186)Open Foundation of Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering(No.JDSX2023003)+1 种基金the National Key Research and Development Program of China(Nos.2022YFB2402200 and 2019YFA0705600)the Fundamental Research Funds for the Central Universities of China(Nos.63233017,63231002,and 63231198).
文摘P2-type layered Ni–Mn-based oxides are vital cathode materials for sodiumion batteries(SIBs)due to their high discharge capacity and working voltage.However,they suffer from the detrimental P2→O_(2) phase transition induced by the O^(2-)−O^(2-)−electrostatic repulsion upon high-voltage charge,which leads to rapid capacity fade.Herein,we construct a P2-type Ni–Mn-based layered oxide cathode with a core-shell structure(labeled as NM–Mg–CS).The P2-Na_(0.67)[Ni_(0.25)Mn_(0.75)]O_(2)(NM)core is enclosed by the robust P2-Na_(0.67)[Ni_(0.21)Mn_(0.71)Mg_(0.08)]O_(2)(NM–Mg)shell.The NM–Mg–CS exhibits the phase-transition-free character with mitigated volume change because the confinement effect of shell is conductive to inhibit the irreversible phase transition of the core material.As a result,it drives a high capacity retention of 81%after 1000 cycles at 5 C with an initial capacity of 78mA h/g.And the full cell with the NM–Mg–CS cathode and hard carbon anode delivers stable capacities over 250 cycles.The successful construction of the core-shell structure in P2-type layered oxides sheds light on the development of high-capacity and long-life cathode materials for SIBs.
基金supported by the National Natural Science Foundation of China (U1607128,52102302 and 21521005)Natural Science Foundation of Beijing (2222020)+1 种基金the Young Talent Support Plan and Siyuan Scholar of Xi’an Jiaotong University (DQ6J011 and DQ1J009)State Key Laboratory of Electrical Insulation and Power Equipment (EIPE23313)
文摘Sodium-ion intercalation oxides generally possess high compositional diversity according to their different stacking sequences.The sodium diffusion pathway in layered P-type materials used in sodium-ion batteries is open,which can increase their rate capability by directly transmitting Na+between adjacent triangular prismatic channels,rather than passing through an intermediate tetrahedral site in O-type structure.However,how the structure chemistry of the P-type oxides determines their electrochemical properties has not been fully understood yet.Herein,by comparing the crystalline structures,electrochemical behaviors,ion/electron transport dynamics of a couple of P-type intercalation cathodes,P2-Na_(2/3)Ni1/3Mn_(2/3)O_(2)and P3-Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)with the same compositions,we demonstrate experimentally and computationally that the P2 phase delivers better cycling stability and rate capability than the P3 counterpart due to the predominant contribution of the faster intrinsic Na diffusion kinetics in the P2 bulk.We also point out that it is the electronic conductivity that captures the key electrochemistry of layered P3-type materials and makes them possible to enhance the sodium storage performance.The results reveal that the correlation between stacking structure and functional properties in two typical layered P-type cathodes,providing new guidelines for preparing and designing alkali-metal layered oxide materials with improved battery performance.
