The successful synthesis of the pentazolate anion(cyclo-N-5)has been a great breakthrough in the field of energetic materials.However,the detection methods for these energetic materials based on the pentazolate anion ...The successful synthesis of the pentazolate anion(cyclo-N-5)has been a great breakthrough in the field of energetic materials.However,the detection methods for these energetic materials based on the pentazolate anion are quite rare.Herein,two fluorescent probes for cyclo-N-5anion were designed.Sensor 1(TPE2N)was synthesized with a tetraphenylethylene functionalized by two cationic groups which can generate strong electrostatic interactions with pentazolate anion and result in specific fluorescent changes.Sensor 2 was designed based on sensor 1 and supramolecular cucurbit[7]uril(CB[7]).The unique structural features of CB[7]provide sites for the interaction between the cations and N-5anion in its cavity,which would generate a platform for the detection and enhance the recognition performance.Isothermal titration calorimetry(ITC)experiment and fluorescence titration experiment indicate the binding molar ratio between sensor 1 with CB[7]is 1:2.Both sensors display typical aggregation-induced emission(AIE)features and good water-solubility.The sensors demonstrate excellent sensitivity to pentazole hydrazine salt with high enhancement constant(sensor 1:1.34×10^(6);sensor 2:3.78×10^(6))and low limit of detection(LOD:sensor 1=4.33μM;sensor 2=1.54μM).The formation of an AIE-based supramolecular sensor effectively improves the sensitivity to N-5anion.In addition,the probes also have good selectivity of N-5anion salts.The research would shed some light on the design of novel fluorescent sensors to detect pentazolate-based molecules and provides an example of supramolecular chemistry combined with fluorescent probes.展开更多
Pentazolate compounds have attracted extensive attention as high energy density materials.The synthesis and recovery of pentazolate compounds is of great importance for their potential applications.Here,we report the ...Pentazolate compounds have attracted extensive attention as high energy density materials.The synthesis and recovery of pentazolate compounds is of great importance for their potential applications.Here,we report the synthesis of Pmn2_(1)-NaN_(5)and Pm-Na_(2)N_(5)through compressing and laser heating pure NaN_(3)at~60 GPa.Upon decompression,the pressureinduced structural transition from Pmn2_(1)-NaN_(5)into Cm-NaN_(5)is observed in the pressure range of 14-23 GPa for the first time.The cyclo-N_(5)^(-)can be traced down to 4.7 GPa at room temperature and recovered to ambient pressure under low temperature condition(up to 160 K).The Pm-Na_(2)N_(5)is suggested to decompose into the P4/mmm-NaN_(2)at 23 GPa,and be stable at ambient conditions.This work provides insight into the high-pressure behaviors of pentazolate compounds and an alternative way to stabilize energetic polynitrogen compounds.展开更多
The search for high energy density materials(HEDMs)in polymeric nitrogen compounds has gained considerable attention.Previous theoretical predictions and experiments have revealed that metal ions can be used to stabil...The search for high energy density materials(HEDMs)in polymeric nitrogen compounds has gained considerable attention.Previous theoretical predictions and experiments have revealed that metal ions can be used to stabilize the pentazolate(N-5)anion.In this work,by employing a machine learning-accelerated crystal structure searching method and first-principles calculations,we found that the new pentazolate salts,CaN(10)and BaN(10),are energetically favorable at high pressures.Phonon dispersion calculations reveal that they are quenchable at ambient pressure.Ab initio molecular dynamics simulations verify their dynamic stability at finite temperature.Bader charge and electron localization function illustrates that alkaline earth atoms serve as electron donors,contributing to the stability of N5 rings.Bonding calculations reveal covalent bonds between nitrogen atoms and weak interactions between N5 rings.Similar to other pentazolate salts,these polymeric nitrides have high energy densities of approximately 2.35 kJ/g for CaN(10)and 1.32 kJ/g for BaN(10).The predictions of CaN(10)and BaN(10)structures indicate that these salts are potential candidates for green nitrogen-rich HEDMs.展开更多
Subject Code:E04With the support by the National Natural Science Foundation of China,a major breakthrough has been made by the group led by Prof.Lu Ming(陆明)from Nanjing University of Science&Technology.The relat...Subject Code:E04With the support by the National Natural Science Foundation of China,a major breakthrough has been made by the group led by Prof.Lu Ming(陆明)from Nanjing University of Science&Technology.The related research achievement entitled“A series of energetic metal pentazolate hydrates”was published展开更多
In this study,based on two attractive energetic compounds pentazole(PZ) and tetraazacubane(TAC),a new family of high energy and high nitrogen compounds pentazolyltetraazacubanes were designed.Then,a different number o...In this study,based on two attractive energetic compounds pentazole(PZ) and tetraazacubane(TAC),a new family of high energy and high nitrogen compounds pentazolyltetraazacubanes were designed.Then,a different number of NH2 or NO2 groups were introduced into the system to further adjust the property.The structures,properties,and the structure-property relationship of designed molecules were investigated theoretically.The results showed that all nine designed compounds have extremely high heat of formation(HOF,1226-2734 kJ/mol),good density(1,73-1.88 g/cm3),high detonation velocity(8.30-9.35 km/s),high detonation pressure(29.8-39.7 GPa) and acceptable sensitivity(△V:41-87 A3).These properties could be effectively positive adjusted by replacing one or two PZ rings by NH2 or/and NO2 groups,especially for the energy and sensitivity performance,which were increased and decreased obviously,respectively.As a result,two designed pentazolyltetraazacubanes were predicted to have higher energy and lower sensitivity than the famous high energy compound in use 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane,while two others have better co mbination property than 1,3,5-Trinitro-1,3,5-triazacyclohexane.In all,four new pentazolyltetraazacubanes with good combination performance were successfully designed by combining PZ with TAC,and the further property adjustment strategy of introducing a suitable amount of NH2/NO2 groups into the system.This work may help develop new cage energetic compounds.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.22175093 and 22007047)the Natural Science Foundation of Jiangsu Province(Grant No.BK20200474)the China Postdoctoral Science Foundation(Grant No.2022M721615)。
文摘The successful synthesis of the pentazolate anion(cyclo-N-5)has been a great breakthrough in the field of energetic materials.However,the detection methods for these energetic materials based on the pentazolate anion are quite rare.Herein,two fluorescent probes for cyclo-N-5anion were designed.Sensor 1(TPE2N)was synthesized with a tetraphenylethylene functionalized by two cationic groups which can generate strong electrostatic interactions with pentazolate anion and result in specific fluorescent changes.Sensor 2 was designed based on sensor 1 and supramolecular cucurbit[7]uril(CB[7]).The unique structural features of CB[7]provide sites for the interaction between the cations and N-5anion in its cavity,which would generate a platform for the detection and enhance the recognition performance.Isothermal titration calorimetry(ITC)experiment and fluorescence titration experiment indicate the binding molar ratio between sensor 1 with CB[7]is 1:2.Both sensors display typical aggregation-induced emission(AIE)features and good water-solubility.The sensors demonstrate excellent sensitivity to pentazole hydrazine salt with high enhancement constant(sensor 1:1.34×10^(6);sensor 2:3.78×10^(6))and low limit of detection(LOD:sensor 1=4.33μM;sensor 2=1.54μM).The formation of an AIE-based supramolecular sensor effectively improves the sensitivity to N-5anion.In addition,the probes also have good selectivity of N-5anion salts.The research would shed some light on the design of novel fluorescent sensors to detect pentazolate-based molecules and provides an example of supramolecular chemistry combined with fluorescent probes.
基金Project supported by the National Key R&D Program of China(Grant No.2018YFA0305900)the National Nat-ural Science Foundation of China(Grant Nos.12174143,11634004,11847094,and 11804384)JLU Science and Technology Innovative Research Team(Grant No.2017TD-01)。
文摘Pentazolate compounds have attracted extensive attention as high energy density materials.The synthesis and recovery of pentazolate compounds is of great importance for their potential applications.Here,we report the synthesis of Pmn2_(1)-NaN_(5)and Pm-Na_(2)N_(5)through compressing and laser heating pure NaN_(3)at~60 GPa.Upon decompression,the pressureinduced structural transition from Pmn2_(1)-NaN_(5)into Cm-NaN_(5)is observed in the pressure range of 14-23 GPa for the first time.The cyclo-N_(5)^(-)can be traced down to 4.7 GPa at room temperature and recovered to ambient pressure under low temperature condition(up to 160 K).The Pm-Na_(2)N_(5)is suggested to decompose into the P4/mmm-NaN_(2)at 23 GPa,and be stable at ambient conditions.This work provides insight into the high-pressure behaviors of pentazolate compounds and an alternative way to stabilize energetic polynitrogen compounds.
基金financial support from the National Key R&D Program of China(Grant No.2016YFA0300404)the National Natural Science Foundation of China(Grant Nos.11974162,and 11834006)+1 种基金the Fundamental Research Funds for the Central Universitiesfinancial support from the Project funded by China Postdoctoral Science Foundation(Grant No.2019M651767)。
文摘The search for high energy density materials(HEDMs)in polymeric nitrogen compounds has gained considerable attention.Previous theoretical predictions and experiments have revealed that metal ions can be used to stabilize the pentazolate(N-5)anion.In this work,by employing a machine learning-accelerated crystal structure searching method and first-principles calculations,we found that the new pentazolate salts,CaN(10)and BaN(10),are energetically favorable at high pressures.Phonon dispersion calculations reveal that they are quenchable at ambient pressure.Ab initio molecular dynamics simulations verify their dynamic stability at finite temperature.Bader charge and electron localization function illustrates that alkaline earth atoms serve as electron donors,contributing to the stability of N5 rings.Bonding calculations reveal covalent bonds between nitrogen atoms and weak interactions between N5 rings.Similar to other pentazolate salts,these polymeric nitrides have high energy densities of approximately 2.35 kJ/g for CaN(10)and 1.32 kJ/g for BaN(10).The predictions of CaN(10)and BaN(10)structures indicate that these salts are potential candidates for green nitrogen-rich HEDMs.
文摘Subject Code:E04With the support by the National Natural Science Foundation of China,a major breakthrough has been made by the group led by Prof.Lu Ming(陆明)from Nanjing University of Science&Technology.The related research achievement entitled“A series of energetic metal pentazolate hydrates”was published
基金supported by the Natural Science Foundation of Nanjing Institute of Technology (CKJA201603)the Natural Science Foundation of Jiangsu Province(BK20170761,BK20160774)+3 种基金the Jiangsu Key Laboratory Opening Project of Advanced Structural Materials and Application Technology (ASMA201707)Science Innovation Project for Undergraduates of Jiangsu Province (201811276023Z)Outstanding Scientific and Technological Innovation Team in Colleges and Universities of Jiangsu ProvinceJiangsu Overseas Visiting Scholar Program for University Prominent Young & Middle-aged Teachers and Presidents
文摘In this study,based on two attractive energetic compounds pentazole(PZ) and tetraazacubane(TAC),a new family of high energy and high nitrogen compounds pentazolyltetraazacubanes were designed.Then,a different number of NH2 or NO2 groups were introduced into the system to further adjust the property.The structures,properties,and the structure-property relationship of designed molecules were investigated theoretically.The results showed that all nine designed compounds have extremely high heat of formation(HOF,1226-2734 kJ/mol),good density(1,73-1.88 g/cm3),high detonation velocity(8.30-9.35 km/s),high detonation pressure(29.8-39.7 GPa) and acceptable sensitivity(△V:41-87 A3).These properties could be effectively positive adjusted by replacing one or two PZ rings by NH2 or/and NO2 groups,especially for the energy and sensitivity performance,which were increased and decreased obviously,respectively.As a result,two designed pentazolyltetraazacubanes were predicted to have higher energy and lower sensitivity than the famous high energy compound in use 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane,while two others have better co mbination property than 1,3,5-Trinitro-1,3,5-triazacyclohexane.In all,four new pentazolyltetraazacubanes with good combination performance were successfully designed by combining PZ with TAC,and the further property adjustment strategy of introducing a suitable amount of NH2/NO2 groups into the system.This work may help develop new cage energetic compounds.