The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes ...The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes regarded as the main cause of battery fire.Herein,a series of solid-state polyphosphate oligomers(SPPO)as a three-in-one electrolyte that integrated the roles of lithium salt,dissociation matrix,and flame retardant were synthesized.The well-designed SPPO electrolytes showed an optimal ionic conductivity of 5.5×10^(-4)S cm-1at 30℃,an acceptable electrochemical window up to 4.0 V vs.Li/Li+,and lithium ion transference number of 0.547.Stable Li-ion stripping/plating behavior for 500 h of charge-discharge cycles without internal short-circuit in a Li|SPPO|Li cell was confirmed,together with outstanding interface compatibility between the SPPO electrolyte and lithium foil.The optimal Li|SPPO|LiFePO4cell presented good reversible discharge capacity of 149.4 mA h g-1at 0.1 C and Coulombic efficiency of 96.4%after 120 cycles.More importantly,the prepared SPPO cannot be ignited by the lighter fire and show a limited-oxygen-index value as high as 35.5%,indicating splendid nonflammable nature.The SPPO could be a promising candidate as a three-in-one solid-state electrolyte for the improved safety of rechargeable lithium batteries.展开更多
Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,c...Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,causing the electrolyte overconsumption,specific energy decline,and even safety hazards for battery devices.To build better cathodes,we propose to substitute carbons by In-doped SnO_(2)(ITO)nano ceramics that own three-in-one functionalities:1)using conductive ITO enables minimizing the total carbon content to an extremely low mass ratio(~3%)in cathodes,elevating the electrode tap density and averting the electrolyte overuse;2)polar ITO nanoclusters can serve as robust anchors toward Li polysulfide(LiPS)by electrostatic adsorption or chemical bond interactions;3)they offer catalysis centers for liquid–solid phase conversions of S-based actives.Also,such ceramics are intrinsically nonflammable,preventing S cathodes away from thermal runaway or explosion.These merits entail our configured cathodes with high tap density(1.54 g cm^(−3)),less electrolyte usage,good security for flame retardance,and decent Li-storage behaviors.With lean and LiNO_(3)-free electrolyte,packed full cells exhibit excellent redox kinetics,suppressed LiPS shuttling,and excellent cyclability.This may trigger great research enthusiasm in rational design of low-carbon and safer S cathodes.展开更多
LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible cap...LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible capacity limits its replacement for LiCoO_(2) in high-end digital field.Herein,three-in-one modification,Na-doping and Al_(2)O_(3)@Li_(3)BO_(3) dual-coating simultaneously,is explored for single-crystalline LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(N-NCM@AB),which exhibits excellent high-voltage performance.N-NCM@AB displays a discharge-specific capacity of 201.8 mAh g^(−1) at 0.2 C with a high upper voltage of 4.6 V and maintains 158.9 mAh g^(−1) discharge capacity at 1 C over 200 cycles with the corresponding capacity retention of 87.8%.Remarkably,the N-NCM@AB||graphite pouch-type full cell retains 81.2% of its initial capacity with high working voltage of 4.4 V over 1600 cycles.More importantly,the fundamental understandings of three-in-one modification on surface morphology,crystal structure,and phase transformation of N-NCM@AB are clearly revealed.The Na+doped into the Li–O slab can enhance the bond energy,stabilize the crystal structure,and facilitate Li+transport.Additionally,the interior surface layer of Li^(+)-ions conductor Li_(3)BO_(3) relieves the charge transfer resistance with surface coating,whereas the outer surface Al_(2)O_(3) coating layer is beneficial for reducing the active materials loss and alleviating the electrode/electrolyte parasite reaction.This three-in-one strategy provides a reference for the further research on the performance attenuation mechanism of NCM,paving a new avenue to boost the high-voltage performance of NCM cathode in Li-ion batteries.展开更多
Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome...Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome before offering real benefits,such as poor stability,poor dispersibility as well as difficulty in tailoring other functions.Here,a“three-in-one”mitochondria-targeted BP nano-platform,called as BPQD-PEG-TPP,was designed.In this nano-platform,BPQDs were covalently grafted with a heterobifunctional PEG,in which one end was an aryl diazo group capable of reacting with BPQDs to form a covalent bond and the other end was a mitochondria-targeted triphenylphosphine(TPP)group.In addition to its excellent near-infrared photothermal properties,BPQD-PEG-TPP had much enhanced stability and dispersibility under physiological conditions,efficient mitochondria targeting and promoted ROS production through a photothermal effect.Both in vitro and in vivo experiments demonstrated that BPQD-PEG-TPP performed much superior photothermal cytotoxicity than BPQDs and BPQD-PEG as the mitochondria targeted PTT.Thus this“three-in-one”nanoplatform fabricated through polymer grafting,with excellent stability,dispersibility and negligible side effects,might be a promising strategy for mitochondria-targeted photothermal cancer therapy.展开更多
Industry progressing caused the pollutants into the surface and groundwater,including organic pollutants such as phenylenediamine(PD)and heavy metals such as Cr(Ⅵ).Herein,a simple"three-in-one"strategy base...Industry progressing caused the pollutants into the surface and groundwater,including organic pollutants such as phenylenediamine(PD)and heavy metals such as Cr(Ⅵ).Herein,a simple"three-in-one"strategy based on MOF-199 was demonstrated.The MOF-199 catalytic system could be used for the rapid detection of Cr(Ⅵ)and o-phenylenediamine(OPD)in linear ranges of 0.5-50.0μmol/L and 7.0-250.0μmol/L,with the limits of detection of 0.1 and 0.5μmol/L,respectively.This method can also efficiently discriminate PD isomers in just 15 min.Meanwhile,Cr(Ⅵ)was reduced to Cr(Ⅲ)and the elimination of OPD was carried out.Given simple synthesis,high sensitivity,easy operation,and low cost,this method presented a potential platform for on-site detection of pollutants in water samples.展开更多
The intellectual property("IP") judicial system comprises two parts: IP judicial organization and IP judicial mechanism. China’s IP judicial system reform should be carried along with the construction of sp...The intellectual property("IP") judicial system comprises two parts: IP judicial organization and IP judicial mechanism. China’s IP judicial system reform should be carried along with the construction of specialized IP courts, aiming to establish a specialized IP judicial system. Such a system contains five elements. First, the nation-wide specialized IP courts are both courts of first instance and of appeal, which is a mode of "first instance + appeal". Meanwhile, a state-level high court or an IP circuit court of the Supreme People’s Court("the Supreme Court") should be established. Second, IP courts should not be set up everywhere, instead, they should be set up in 10-13 central cities, supplemented with detached tribunals. Third, the judicial mechanism in the IP courts should be "3-in-1", in which civil, administrative and criminal suits are heard by one court. Fourth, the manner of reasoning inherited from administrative authority principles of the civil law system should be avoided, and judicial organs should be given the authority to make substantial judgments on the validity of IP. Finally, in technical cases, a multiidentification mechanism for technical facts should be set up, by establishing systems such as technical investigators, expert consultation, expert juries, and judicial appraisal. Thus, an overarching IP judicial system will be formed, which will separate IP trials from others and strengthen the professional traits of IP trails. Such a judicial system is an optimized choice conforming to the construction of an innovative country and is sufficient for China to present a picture of "strong judicial protection" of IP to the world.展开更多
Based on credit bank,the"1+X"certificate system is a"flyover"for learners to interchange between the academic and vocational education.It is a significant innovation to promote high-quality vocatio...Based on credit bank,the"1+X"certificate system is a"flyover"for learners to interchange between the academic and vocational education.It is a significant innovation to promote high-quality vocational education development and enhance the influence of national vocational education.Vocational colleges can implement"1+X"certificate system via the credit bank and in turn,the popularization of the"1+X"certificate system would enrich and improve the former.China's development of the credit bank and the existing research on the"1+X"certificate system are analyzed to look for a way in the collaboration of credit bank and the T+X"certificate system.The firm collaboration as well as the connection and optimization between government,schools,and enterprises as one body form a new talent training mode with the"1+X"certificate system that integrates academy and certificates as well as involving both,schools and enterprises according to China's credit bank concept.展开更多
基金the financial support of the National Natural Science Foundation of China(21961044,22169024)the Yunnan Fundamental Research Projects(202105AC160072,202101BC070001-019,202101AT070280,202102AB080017)the Yunnan University’s Research Innovation Fund for graduate students(2021Y394)。
文摘The development of flame retardant or nonflammable electrolytes is the key to improve the safety of lithium batteries,owing to inflammable organic solvents and polymer matrix in common liquid and polymer electrolytes regarded as the main cause of battery fire.Herein,a series of solid-state polyphosphate oligomers(SPPO)as a three-in-one electrolyte that integrated the roles of lithium salt,dissociation matrix,and flame retardant were synthesized.The well-designed SPPO electrolytes showed an optimal ionic conductivity of 5.5×10^(-4)S cm-1at 30℃,an acceptable electrochemical window up to 4.0 V vs.Li/Li+,and lithium ion transference number of 0.547.Stable Li-ion stripping/plating behavior for 500 h of charge-discharge cycles without internal short-circuit in a Li|SPPO|Li cell was confirmed,together with outstanding interface compatibility between the SPPO electrolyte and lithium foil.The optimal Li|SPPO|LiFePO4cell presented good reversible discharge capacity of 149.4 mA h g-1at 0.1 C and Coulombic efficiency of 96.4%after 120 cycles.More importantly,the prepared SPPO cannot be ignited by the lighter fire and show a limited-oxygen-index value as high as 35.5%,indicating splendid nonflammable nature.The SPPO could be a promising candidate as a three-in-one solid-state electrolyte for the improved safety of rechargeable lithium batteries.
基金support by the National Natural Science Foundation of China(51802269,21773138)Fundamental Research Funds for the Central Universities(XDJK2019AA002)+1 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(cx2018027)the innovation platform for academicians of Hainan province.
文摘Using porous carbon hosts in cathodes of Li-S cells can disperse S actives and offset their poor electrical conductivity.However,such reservoirs would in turn absorb excess electrolyte solvents to S-unfilled regions,causing the electrolyte overconsumption,specific energy decline,and even safety hazards for battery devices.To build better cathodes,we propose to substitute carbons by In-doped SnO_(2)(ITO)nano ceramics that own three-in-one functionalities:1)using conductive ITO enables minimizing the total carbon content to an extremely low mass ratio(~3%)in cathodes,elevating the electrode tap density and averting the electrolyte overuse;2)polar ITO nanoclusters can serve as robust anchors toward Li polysulfide(LiPS)by electrostatic adsorption or chemical bond interactions;3)they offer catalysis centers for liquid–solid phase conversions of S-based actives.Also,such ceramics are intrinsically nonflammable,preventing S cathodes away from thermal runaway or explosion.These merits entail our configured cathodes with high tap density(1.54 g cm^(−3)),less electrolyte usage,good security for flame retardance,and decent Li-storage behaviors.With lean and LiNO_(3)-free electrolyte,packed full cells exhibit excellent redox kinetics,suppressed LiPS shuttling,and excellent cyclability.This may trigger great research enthusiasm in rational design of low-carbon and safer S cathodes.
基金We gratefully acknowledge the financial support from the National Natural Science Foundation of China(52070194,51902347,51908555,and 51822812)Natural Science Foundation of Hunan Province(2020JJ5741)the Graduate Innovation Project of Central South University(2020zzts093).
文摘LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2) is extensively researched as one of the most widely used commercially materials for Li-ion batteries at present.However,the poor high-voltage performance(≥4.3 V)with low reversible capacity limits its replacement for LiCoO_(2) in high-end digital field.Herein,three-in-one modification,Na-doping and Al_(2)O_(3)@Li_(3)BO_(3) dual-coating simultaneously,is explored for single-crystalline LiNi_(0.5)Co_(0.2)Mn_(0.3)O_(2)(N-NCM@AB),which exhibits excellent high-voltage performance.N-NCM@AB displays a discharge-specific capacity of 201.8 mAh g^(−1) at 0.2 C with a high upper voltage of 4.6 V and maintains 158.9 mAh g^(−1) discharge capacity at 1 C over 200 cycles with the corresponding capacity retention of 87.8%.Remarkably,the N-NCM@AB||graphite pouch-type full cell retains 81.2% of its initial capacity with high working voltage of 4.4 V over 1600 cycles.More importantly,the fundamental understandings of three-in-one modification on surface morphology,crystal structure,and phase transformation of N-NCM@AB are clearly revealed.The Na+doped into the Li–O slab can enhance the bond energy,stabilize the crystal structure,and facilitate Li+transport.Additionally,the interior surface layer of Li^(+)-ions conductor Li_(3)BO_(3) relieves the charge transfer resistance with surface coating,whereas the outer surface Al_(2)O_(3) coating layer is beneficial for reducing the active materials loss and alleviating the electrode/electrolyte parasite reaction.This three-in-one strategy provides a reference for the further research on the performance attenuation mechanism of NCM,paving a new avenue to boost the high-voltage performance of NCM cathode in Li-ion batteries.
基金We are grateful for the financial support from National Natural Science Foundation of China(51703258,81772449 and 81971081)Guangzhou science technology and innovation commission(201804010309 and 201803010090)Science,Technology&Innovation Commission of Shenzhen Municipality(JCYJ20180307154606793 and JCYJ20180507181654186).
文摘Black phosphorus(BP)nano-materials,especially BP quantum dots(BPQDs),performs outstanding photothermal antitumor effects,excellent biocompatibility and biodegradability.However,there are several challenges to overcome before offering real benefits,such as poor stability,poor dispersibility as well as difficulty in tailoring other functions.Here,a“three-in-one”mitochondria-targeted BP nano-platform,called as BPQD-PEG-TPP,was designed.In this nano-platform,BPQDs were covalently grafted with a heterobifunctional PEG,in which one end was an aryl diazo group capable of reacting with BPQDs to form a covalent bond and the other end was a mitochondria-targeted triphenylphosphine(TPP)group.In addition to its excellent near-infrared photothermal properties,BPQD-PEG-TPP had much enhanced stability and dispersibility under physiological conditions,efficient mitochondria targeting and promoted ROS production through a photothermal effect.Both in vitro and in vivo experiments demonstrated that BPQD-PEG-TPP performed much superior photothermal cytotoxicity than BPQDs and BPQD-PEG as the mitochondria targeted PTT.Thus this“three-in-one”nanoplatform fabricated through polymer grafting,with excellent stability,dispersibility and negligible side effects,might be a promising strategy for mitochondria-targeted photothermal cancer therapy.
基金supported by the National Natural Science Foundation of China(NSFC)Fund(22174058,U21A20282)Sci-tech plan projects of Gansu province(22CX3GA023).
文摘Industry progressing caused the pollutants into the surface and groundwater,including organic pollutants such as phenylenediamine(PD)and heavy metals such as Cr(Ⅵ).Herein,a simple"three-in-one"strategy based on MOF-199 was demonstrated.The MOF-199 catalytic system could be used for the rapid detection of Cr(Ⅵ)and o-phenylenediamine(OPD)in linear ranges of 0.5-50.0μmol/L and 7.0-250.0μmol/L,with the limits of detection of 0.1 and 0.5μmol/L,respectively.This method can also efficiently discriminate PD isomers in just 15 min.Meanwhile,Cr(Ⅵ)was reduced to Cr(Ⅲ)and the elimination of OPD was carried out.Given simple synthesis,high sensitivity,easy operation,and low cost,this method presented a potential platform for on-site detection of pollutants in water samples.
基金This article is the phased achievement of the Beijing Social Science Fund Major Project:“Research on the Establishment of the Beijing Intellectual Property Court”(15ZDA05).
文摘The intellectual property("IP") judicial system comprises two parts: IP judicial organization and IP judicial mechanism. China’s IP judicial system reform should be carried along with the construction of specialized IP courts, aiming to establish a specialized IP judicial system. Such a system contains five elements. First, the nation-wide specialized IP courts are both courts of first instance and of appeal, which is a mode of "first instance + appeal". Meanwhile, a state-level high court or an IP circuit court of the Supreme People’s Court("the Supreme Court") should be established. Second, IP courts should not be set up everywhere, instead, they should be set up in 10-13 central cities, supplemented with detached tribunals. Third, the judicial mechanism in the IP courts should be "3-in-1", in which civil, administrative and criminal suits are heard by one court. Fourth, the manner of reasoning inherited from administrative authority principles of the civil law system should be avoided, and judicial organs should be given the authority to make substantial judgments on the validity of IP. Finally, in technical cases, a multiidentification mechanism for technical facts should be set up, by establishing systems such as technical investigators, expert consultation, expert juries, and judicial appraisal. Thus, an overarching IP judicial system will be formed, which will separate IP trials from others and strengthen the professional traits of IP trails. Such a judicial system is an optimized choice conforming to the construction of an innovative country and is sufficient for China to present a picture of "strong judicial protection" of IP to the world.
基金Supported by Beying Young Famous Teachers Program"Research on the telepresence in online class under the background of mobile internet background."。
文摘Based on credit bank,the"1+X"certificate system is a"flyover"for learners to interchange between the academic and vocational education.It is a significant innovation to promote high-quality vocational education development and enhance the influence of national vocational education.Vocational colleges can implement"1+X"certificate system via the credit bank and in turn,the popularization of the"1+X"certificate system would enrich and improve the former.China's development of the credit bank and the existing research on the"1+X"certificate system are analyzed to look for a way in the collaboration of credit bank and the T+X"certificate system.The firm collaboration as well as the connection and optimization between government,schools,and enterprises as one body form a new talent training mode with the"1+X"certificate system that integrates academy and certificates as well as involving both,schools and enterprises according to China's credit bank concept.