On account of excellent thermal physical properties, molten nitrates/nitrites salt has been widely employed in heat transfer and thermal storage industry, especially in concentrated solar power system. The thermal sta...On account of excellent thermal physical properties, molten nitrates/nitrites salt has been widely employed in heat transfer and thermal storage industry, especially in concentrated solar power system. The thermal stability study of molten nitrate/nitrite salt is of great importance for this system, and the decomposition mechanism is the most complicated part of it. The oxide species O2^2- and O2^- were considered as intermediates in molten KNO3-NaNO3 while hard to been detected in high temperature molten salt due to their trace concentration and low stability. In this work, the homemade in situ high temperature UV- Vis instrument and a commercial electron paramagnetic resonance were utilized to supply evidence for the formation of superoxide during a slow decomposition process of heat transfer salt (HTS, 53 wt% KNO3/40 wt% NaNO2/7 wt% NaNO3). It is found that the superoxide is more easily generated from molten NaNO2 compared to NaNO3, and it has an absorption band at 420-440 nm in HTS which red shifts as temperature increases. The band is assigned to charge-transfer transition in NaO2 or KO2, responsible for the yellow color of the molten nitrate/nitrite salt. Furthermore, the UV absorption bands of molten NaNO2 and NANO3 are also obtained and compared with that of HTS.展开更多
The present paper contains the effects of the ammonium ion, counter ion, solvent and anion being transferred on the solid-liquid phase transfer equilibrium constant of quaternary ammonium salts. The most striking diff...The present paper contains the effects of the ammonium ion, counter ion, solvent and anion being transferred on the solid-liquid phase transfer equilibrium constant of quaternary ammonium salts. The most striking difference between solid-liquid and liquid-liquid phase transfer equilibriums is that the length of alkyl chain shows a large effect on the latter but little on the former This means that the chain length affects only the hydrophobicity, rather than the lipophilicity.Keywords Quaternary ammonium salt, Phase transfer catalysis, Equilibrium constant, Hydrophobicity, Lipophilicity展开更多
The crystal structure of the compound EDA Ni(dmit) 2 3 (EDA=2 diethylamino 1,3 dithioanylium; dmit=1,3 dithiole 2 thione 4,5 dithiolate)C 25 H 14 NNi 3S 32 , has been determined by single...The crystal structure of the compound EDA Ni(dmit) 2 3 (EDA=2 diethylamino 1,3 dithioanylium; dmit=1,3 dithiole 2 thione 4,5 dithiolate)C 25 H 14 NNi 3S 32 , has been determined by single crystal X ray diffraction at 300K. The crystal is triclinic with space group P1, a=11.252, b=12.192(2), c=20.055(6) , α=108.127(2), β=106.287(8), γ=90.005(9)°; V=2498.3(3) 3, Z=2, M r=1530.38, D c =2.03(2) g/cm 3. Final R and R w values were 0.0603 and 0.0704, respectively. The structure consists of thick layers of stacked Ni(dmit) 2 entities separated by EDA cations. This salt shows semiconducting behaviour with room temperature conductivity of 0.2 Scm -1 and activation energy of 0.11 eV.展开更多
Here we report an in situ assembly growth method that controls the growth of NiTCNQ on the surface of graphdiyne(GDY).The catalytic system of donor–acceptor–donor(GDY/TCNQ/Ni)structure with multiple charge transfer(...Here we report an in situ assembly growth method that controls the growth of NiTCNQ on the surface of graphdiyne(GDY).The catalytic system of donor–acceptor–donor(GDY/TCNQ/Ni)structure with multiple charge transfer(CT)was achieved by controlling the growth of NiTCNQ on the surface of GDY.Significantly,a controlled double layer interface of GDY/TCNQ/Ni was formed.This system implemented simultaneously the two elements we expected(1)an incomplete CT,and(2)the infinite distribution of active sites originating from highly asymmetric surface charge distribution.The high conductivity and typical semiconductor characteristics of the catalyst endows it with high catalytic activity.We found that an electrolytic cell consisting of the CT salt as a catalyst provided a 1.40 V ultra-small cell voltage up to 10 mA cm−2 and the outer GDY film effectively prevented the corrosion of the catalyst.Our study is the first to introduce CT complexes to a novel catalytic material platform for high selectivity of catalysts,and undoubtedly demonstrates the high selectivity,stability,and activity of such catalytic systems,which provides a new space for the development of novel conceptual catalysts.展开更多
The organic single-crystal field-effect transistors using anthracene derivative, H-Ant as an active layer with source/drain electrodes decorated by metal charge transfer salt(Cu TCNQ) were fabricated. We demonstrated ...The organic single-crystal field-effect transistors using anthracene derivative, H-Ant as an active layer with source/drain electrodes decorated by metal charge transfer salt(Cu TCNQ) were fabricated. We demonstrated that this bottom-contact structure displayed an obvious improvement in the electrical characteristics relative to their pristine copper and top-contact gold electrode counterparts. This observation could be ascribed to the lower contact resistance resulting from the energetic match between electrodes and semiconductor.展开更多
基金This work was supported by the "Strategic Priority Research Program, TMSR" of the Chinese Academy of Sciences (No.XD02002400), the National Natural Science Foundation of China (No.51506214), the Hundred Talents Program, CAS and Shanghai Pujiang Program.
文摘On account of excellent thermal physical properties, molten nitrates/nitrites salt has been widely employed in heat transfer and thermal storage industry, especially in concentrated solar power system. The thermal stability study of molten nitrate/nitrite salt is of great importance for this system, and the decomposition mechanism is the most complicated part of it. The oxide species O2^2- and O2^- were considered as intermediates in molten KNO3-NaNO3 while hard to been detected in high temperature molten salt due to their trace concentration and low stability. In this work, the homemade in situ high temperature UV- Vis instrument and a commercial electron paramagnetic resonance were utilized to supply evidence for the formation of superoxide during a slow decomposition process of heat transfer salt (HTS, 53 wt% KNO3/40 wt% NaNO2/7 wt% NaNO3). It is found that the superoxide is more easily generated from molten NaNO2 compared to NaNO3, and it has an absorption band at 420-440 nm in HTS which red shifts as temperature increases. The band is assigned to charge-transfer transition in NaO2 or KO2, responsible for the yellow color of the molten nitrate/nitrite salt. Furthermore, the UV absorption bands of molten NaNO2 and NANO3 are also obtained and compared with that of HTS.
文摘The present paper contains the effects of the ammonium ion, counter ion, solvent and anion being transferred on the solid-liquid phase transfer equilibrium constant of quaternary ammonium salts. The most striking difference between solid-liquid and liquid-liquid phase transfer equilibriums is that the length of alkyl chain shows a large effect on the latter but little on the former This means that the chain length affects only the hydrophobicity, rather than the lipophilicity.Keywords Quaternary ammonium salt, Phase transfer catalysis, Equilibrium constant, Hydrophobicity, Lipophilicity
文摘The crystal structure of the compound EDA Ni(dmit) 2 3 (EDA=2 diethylamino 1,3 dithioanylium; dmit=1,3 dithiole 2 thione 4,5 dithiolate)C 25 H 14 NNi 3S 32 , has been determined by single crystal X ray diffraction at 300K. The crystal is triclinic with space group P1, a=11.252, b=12.192(2), c=20.055(6) , α=108.127(2), β=106.287(8), γ=90.005(9)°; V=2498.3(3) 3, Z=2, M r=1530.38, D c =2.03(2) g/cm 3. Final R and R w values were 0.0603 and 0.0704, respectively. The structure consists of thick layers of stacked Ni(dmit) 2 entities separated by EDA cations. This salt shows semiconducting behaviour with room temperature conductivity of 0.2 Scm -1 and activation energy of 0.11 eV.
基金by a generous grant from the National Key Research and Development Project of China(no.2018YFA0703501)the National Nature Science Foundation of China(nos.21790050,21790051,and 22021002)the Key Program of the Chinese Academy of Sciences(no.XDPB13).
文摘Here we report an in situ assembly growth method that controls the growth of NiTCNQ on the surface of graphdiyne(GDY).The catalytic system of donor–acceptor–donor(GDY/TCNQ/Ni)structure with multiple charge transfer(CT)was achieved by controlling the growth of NiTCNQ on the surface of GDY.Significantly,a controlled double layer interface of GDY/TCNQ/Ni was formed.This system implemented simultaneously the two elements we expected(1)an incomplete CT,and(2)the infinite distribution of active sites originating from highly asymmetric surface charge distribution.The high conductivity and typical semiconductor characteristics of the catalyst endows it with high catalytic activity.We found that an electrolytic cell consisting of the CT salt as a catalyst provided a 1.40 V ultra-small cell voltage up to 10 mA cm−2 and the outer GDY film effectively prevented the corrosion of the catalyst.Our study is the first to introduce CT complexes to a novel catalytic material platform for high selectivity of catalysts,and undoubtedly demonstrates the high selectivity,stability,and activity of such catalytic systems,which provides a new space for the development of novel conceptual catalysts.
基金supported by the National Natural Science Foundation of China(20721061,51033006,51003107,91027043)the China-Denmark Co-project,TRR61(NSFC-DFG Transregio Project)the National Basic Research Program of China(2011CB808400,2011CB932300,2009CB930400)and Chinese Academy of Sciences
文摘The organic single-crystal field-effect transistors using anthracene derivative, H-Ant as an active layer with source/drain electrodes decorated by metal charge transfer salt(Cu TCNQ) were fabricated. We demonstrated that this bottom-contact structure displayed an obvious improvement in the electrical characteristics relative to their pristine copper and top-contact gold electrode counterparts. This observation could be ascribed to the lower contact resistance resulting from the energetic match between electrodes and semiconductor.