Coordination to form polymer is emerging as a new technology for modifying or enhancing the properties of the existed energetic substances in energetic materials area. In this work, guanidine cation CN3 H6+ (Gu) and 3...Coordination to form polymer is emerging as a new technology for modifying or enhancing the properties of the existed energetic substances in energetic materials area. In this work, guanidine cation CN3 H6+ (Gu) and 3-amino-1,2,4-triazole C2H4N4(ATz) were crystallized into NaN5 and two novel energetic coordination polymers(CPs),(NaN5)5[(CH6-N3)N5](N5)3–(1) and(NaN5)2(C2H4N4)(2) were prepared respectively via a self-assembly process. The crystal structure reveals the co-existence of the chelating pentazole anion and organic component in the solid state. In polymer 1, Na+and N5– were coordinated to form a cage structure in which guanidine cation [C(NH2)3]+ was trapped;for polymer 2, a mixedligand system was observed;N5 – and ATz coordinate separately with Na+and form two independent but interweaved nets. In this way, coordination polymer has been successfully utilized to modify specific properties of energetic materials through crystallization. Benefiting from the coordination and weak interactions, the decomposition temperatures of both polymers increase from 111°C(1D structure [Na(H2 O)(N5)]?2 H2 O) to 118.4 and 126.5°C respectively. Moreover, no crystallized H2 O was generated in products to afford the anhydrous compounds of pentazole salts with high heats of formation( >800 kJ mol–1). Compared to traditional energetic materials, the advantage in heats of formation is still obvious for the cyclo-N5– based CPs, which highlights cyclo-N5– as a promising energetic precursor for high energy density materials(HEDMs).展开更多
The coordination polymer poly（nickel-ethylenetetrathiolate） （poly（Ni-ett））, formed by nickel（Ⅱ） and 1,1,2,2-ethenetetrathiolate （ett）, is the most promising N-type organic thermoelectric material ever repor...The coordination polymer poly（nickel-ethylenetetrathiolate） （poly（Ni-ett））, formed by nickel（Ⅱ） and 1,1,2,2-ethenetetrathiolate （ett）, is the most promising N-type organic thermoelectric material ever reported; it is synthesized via potentiostatic deposition, and the effect of different applied potentials on the optimal performance of the polymers is investigated. The optimal thermoelectric property ofpoly（Ni-ett） synthesized at 0.6 V is remarkably greater than that of the polymers synthesized at 1 and 1.6 V, exhibiting a maximum power factor of up to 131.6μW/mK2 at 360 K. Furthermore, the structure-property correlation ofpoly（Ni-ett） is also extensively investigated. X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS） analyses revealed that the larger size of crystalline domains and the higher oxidation state of poly（Ni-ett） synthesized at 0.6 V possibly results in the higher bulk mobility and carrier concentration in the polymer chains, respectively, accounting for the enhanced power factor.展开更多
Au nanoparticle（Au NP）@SiO2@TDA-Eu nanocomposites were prepared by a two-step process： Au NP@SiO2 nanocomposites were prepared by a modified onepot process. Then the europium coordination polymer was deposited on t...Au nanoparticle（Au NP）@SiO2@TDA-Eu nanocomposites were prepared by a two-step process： Au NP@SiO2 nanocomposites were prepared by a modified onepot process. Then the europium coordination polymer was deposited on the surface of the Au NP@SiO2 by mixing 2,2＇-thiodiacetic acid [S（CH2 COO）2^（2-）, TDA] and Eu（NO3）3·6 H2 O in ethanol via a hydrothermal method. The maximum fluorescent enhancement factor of the nanocomposites was 6.81 at 30 nm thickness of silica between the core of the Au NP and the shell of TDA-Eu. The prepared nanocomposites exhibit more sensitive monitoring of reactive oxygen species.展开更多
基金financially supported by the National Natural Science Foundation of China (11702141, 21771108, and U1530101)
文摘Coordination to form polymer is emerging as a new technology for modifying or enhancing the properties of the existed energetic substances in energetic materials area. In this work, guanidine cation CN3 H6+ (Gu) and 3-amino-1,2,4-triazole C2H4N4(ATz) were crystallized into NaN5 and two novel energetic coordination polymers(CPs),(NaN5)5[(CH6-N3)N5](N5)3–(1) and(NaN5)2(C2H4N4)(2) were prepared respectively via a self-assembly process. The crystal structure reveals the co-existence of the chelating pentazole anion and organic component in the solid state. In polymer 1, Na+and N5– were coordinated to form a cage structure in which guanidine cation [C(NH2)3]+ was trapped;for polymer 2, a mixedligand system was observed;N5 – and ATz coordinate separately with Na+and form two independent but interweaved nets. In this way, coordination polymer has been successfully utilized to modify specific properties of energetic materials through crystallization. Benefiting from the coordination and weak interactions, the decomposition temperatures of both polymers increase from 111°C(1D structure [Na(H2 O)(N5)]?2 H2 O) to 118.4 and 126.5°C respectively. Moreover, no crystallized H2 O was generated in products to afford the anhydrous compounds of pentazole salts with high heats of formation( >800 kJ mol–1). Compared to traditional energetic materials, the advantage in heats of formation is still obvious for the cyclo-N5– based CPs, which highlights cyclo-N5– as a promising energetic precursor for high energy density materials(HEDMs).
基金supported by the National Basic Research Program of China (2013CB632506)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDB12000000)+1 种基金Key Project of National Natural Science Foundation of China (51336009)National Natural Science Foundation of China (21290191, 21333011)
文摘The coordination polymer poly（nickel-ethylenetetrathiolate） （poly（Ni-ett））, formed by nickel（Ⅱ） and 1,1,2,2-ethenetetrathiolate （ett）, is the most promising N-type organic thermoelectric material ever reported; it is synthesized via potentiostatic deposition, and the effect of different applied potentials on the optimal performance of the polymers is investigated. The optimal thermoelectric property ofpoly（Ni-ett） synthesized at 0.6 V is remarkably greater than that of the polymers synthesized at 1 and 1.6 V, exhibiting a maximum power factor of up to 131.6μW/mK2 at 360 K. Furthermore, the structure-property correlation ofpoly（Ni-ett） is also extensively investigated. X-ray diffraction （XRD） and X-ray photoelectron spectroscopy （XPS） analyses revealed that the larger size of crystalline domains and the higher oxidation state of poly（Ni-ett） synthesized at 0.6 V possibly results in the higher bulk mobility and carrier concentration in the polymer chains, respectively, accounting for the enhanced power factor.
基金financially supported by the National Natural Science Foundation of China (51702006 and 21501141)the Doctoral research project (ZK2017027) of Baoji University of Arts and Sciencesthe Education Commission of Shaanxi Province (2015JQ6223,12JS114,14JS092 and 17JS009)
文摘Au nanoparticle（Au NP）@SiO2@TDA-Eu nanocomposites were prepared by a two-step process： Au NP@SiO2 nanocomposites were prepared by a modified onepot process. Then the europium coordination polymer was deposited on the surface of the Au NP@SiO2 by mixing 2,2＇-thiodiacetic acid [S（CH2 COO）2^（2-）, TDA] and Eu（NO3）3·6 H2 O in ethanol via a hydrothermal method. The maximum fluorescent enhancement factor of the nanocomposites was 6.81 at 30 nm thickness of silica between the core of the Au NP and the shell of TDA-Eu. The prepared nanocomposites exhibit more sensitive monitoring of reactive oxygen species.
