Deuterium(D),a stable and non-radioactive isotope of hydro-gen,is naturally present in the environment and is distinguishedfrom hydrogen by its greater mass.This mass difference resultsin a reduced stretching frequenc...Deuterium(D),a stable and non-radioactive isotope of hydro-gen,is naturally present in the environment and is distinguishedfrom hydrogen by its greater mass.This mass difference resultsin a reduced stretching frequency of the carbon-deuterium(C-D)bond,leading to lower ground state energy and higher bond dis-sociation energy compared to the carbon-hydrogen(C–H)bond.展开更多
Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines ...Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines remains an important goal in terms of chemical research and industrial application/manufacture.Herein,we developed an efficient and highly selective nitrogen-doped nickel catalyst enriched with Lewis acid sites,which has been applied for to the hydrogenative coupling of nitriles and amines with molecular hydrogen for the synthesis of a train of functionalised and structurally diverse secondary and tertiary amines.Furthermore,catalytic hydrogenation and deuteration of nitriles were achieved under milder conditions,yielding a series of primary amines and deuterated amines with high deuterium incorporation.展开更多
Protein internal dynamics is essential for its function. Exploring the internal dynamics of protein molecules as well as its connection to protein structure and function is a central topic in biophysics. However, the ...Protein internal dynamics is essential for its function. Exploring the internal dynamics of protein molecules as well as its connection to protein structure and function is a central topic in biophysics. However, the atomic motions in protein molecules exhibit a great degree of complexities. These complexities arise from the complex chemical composition and superposition of different types of atomic motions on the similar time scales, and render it challenging to explicitly understand the microscopic mechanism governing protein motions, functions, and their connections. Here, we demonstrate that, by using neutron scattering, molecular dynamics simulation, and deuteration technique, one can address this challenge to a large extent.展开更多
Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herei...Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herein,with D_(2)O as the D source,we first propose an electrocatalytic deuteration strategy for continuous production of deuterated ethylene from acetylene under ambient conditions.Specially,Ag nanoparticles exhibit a very high deuterated ethylene Faradic efficiency of up to 99.3%at-0.6 V vs.reversible hydrogen electrode.Meanwhile,Ag nanoparticles achieve a deuterated ethylene production rate of 3.72×10^(3)mmol h^(-1)g^(-1)cat and an excellent long-term stability with deuterated ethylene Faradaic efficiencies of~95%in a two-electrode flow cell,which substantially outperform state-of-the-art values for previously reported deuterated alkenes.In-situ electrochemical Infrared absorption and Raman spectroscopies reveal superior acetylene absorption and formation of deuterated ethylene on Ag nanoparticles.This efficient electrocatalytic deuteration strategy opens a new window for continuous and economic production of deuterated alkenes.展开更多
A series of deuterated ammonium dihydrogen phosphate(DADP) crystals were grown and their structures were investigated by using powder neutron diffraction method. In the entire composition range, the deuterated level i...A series of deuterated ammonium dihydrogen phosphate(DADP) crystals were grown and their structures were investigated by using powder neutron diffraction method. In the entire composition range, the deuterated level in the crystals is lower compared with the aqueous growth solution. The deuterium segregation coefficient in the crystals decreases with increasing deuterium content of the solution. The deuterium content in the NH_(4)^(+) group is higher than that in H_(2)PO_(4)^(-) group.In addition, the variations of lattice parameters are shown here.展开更多
Deuteration of hydrogen-bonded phase transition crystals can increase the transition temperatures due to the isotope effect. But rare examples show the opposite trend that originates from the structural changes of the...Deuteration of hydrogen-bonded phase transition crystals can increase the transition temperatures due to the isotope effect. But rare examples show the opposite trend that originates from the structural changes of the hydrogen bond, known as the geometric H/D isotope effect. Herein, we report an organic crystal, diethylammonium hydrogen 1,4-terephthalate, exhibits a reversible structural phase transition and dielectric switching. Structural study shows the cations reside in channels formed by one-dimensional hydrogen-bonded anionic chains and undergo an order-disorder transition at around 206 K. The deuterated counterpart shows an elongation of the O…O hydrogen bond by about 0.005 A. This geometric isotope effect releases the internal pressure of the anionic host on the cation vips and results in a downward shift of the phase transition temperature by 10 K.展开更多
Conductivity measurements of deuterated ammonium dihydrogen phosphate （DADP） crystals with different deuterated degrees are described. The conductivities increase with the deuterium content, and the value of the a-d...Conductivity measurements of deuterated ammonium dihydrogen phosphate （DADP） crystals with different deuterated degrees are described. The conductivities increase with the deuterium content, and the value of the a-direction is larger than that of the e-direction. Compared with DKDP crystals, DADP crystals have larger conductivities, which is partly due to the existence of A defects. The ac conductivity over the temperature range 25-170℃has shown a knee in the curve ofln（σT） versus T-1. The conductivity activation energy calculated by the slope of the high temperature region decreases with the deuterium content. The previously reported phase transition is not seen.展开更多
Organic host-vip systems exhibiting room-temperature phosphorescence(RTP)hold great promise for sensing,encryption,and bioimaging.However,achieving both long lifetimes and high efficiency remains challenging,as enha...Organic host-vip systems exhibiting room-temperature phosphorescence(RTP)hold great promise for sensing,encryption,and bioimaging.However,achieving both long lifetimes and high efficiency remains challenging,as enhanced spin-orbit coupling(SOC)often competes with efficient intersystem crossing(ISC).We report an isotope-engineering strategy that overcomes the lifetime-efficiency trade-off in classical carbazole(Cz)host-vip systems.Doping just 0.5 wt%of deuterated 1H-benzo[f]indole(BdD8)into Cz extends the RTP lifetime from 0.485 to 1.771 s,a 3.65-fold enhancement without compromising the phosphorescence quantum yield.Replacing the N-H group in BdD8 with a CD3 moiety(BdD8CD3)and using a methylated host(CzCH3)further extends the RTP lifetime to 1.870 s.This improvement arises from isotope-induced suppression of non-radiative decay and enhancement of ISC,as evidenced by a reduction in the non-radiative rate from 2.01 to 0.51 s^(-1) and an increase in the ISC rate from 4.91×10^(7) s^(-1) to 6.21×10^(7) s^(-1).Building on this success,we applied the strategy to benzo[b]carbazole(BCz)derivatives,which similarly exhibited enhanced RTP performance.Finally,we demonstrate time-resolved multi-information encoding enabled by this ultralong afterglow system.展开更多
Developing green and practical D-labeling techniques is valuable and in high demand for medical chemistry,mechanistic studies,and materials science.Although dearomatic deuteration of simple aromatic systems represents...Developing green and practical D-labeling techniques is valuable and in high demand for medical chemistry,mechanistic studies,and materials science.Although dearomatic deuteration of simple aromatic systems represents an attractive protocol to access D-labeled compounds,the inherent chemical stability of(het)aromatics leaves successful examples rather scarce.Different from transition metal catalysis,which involves dangerous and expensive deuterium sources,and harsh reaction conditions,represented herein is the first electrophotocatalytic platform for dearomative deuteration of inert(het)arenes.Taking economical D_(2)O as the deuterium source and organic N,N-bis(2,6-diisopropylphenyl)perylene-3,4,9,10-bis(dicarboximide)as the electrophotocatalyst,Birch-type deuteration of(het)aromatics is realized with excellent site-selectivity,good functional group compatibility,and high D-incorporation.Late-stage deuteration of complex pharmaceuticals and gram-scale scale-up are easily implemented.This methodology overcomes existing synthetic challenges,and no overreduction reaction occurs.Moreover,the electrophotocatalytic platform works well with renewable solar-to-electricity,offering an effective way to prepare synthetically useful deuterated molecules.展开更多
The advent of the passivating contact concept and its accelerated development have propelled crystalline silicon(c-Si)solar cells into a new era,establishing them as a driving force behind the latest breakthroughs in ...The advent of the passivating contact concept and its accelerated development have propelled crystalline silicon(c-Si)solar cells into a new era,establishing them as a driving force behind the latest breakthroughs in photovoltaic(PV)conversion efficiency.The continual refinement of passivation performance is pivotal to the fabrication of high-efficiency devices.Here,we report a novel deuteration/hydrogenation hybrid strategy involving the deliberate incorporation of deuterium(D,2H)via atmosphere annealing to neutralize defects and enhance the passivation performance of tunnel oxide passivating contact(TOPCon)solar cells.Our findings reveal that hydrogen and deuterium can coexist within the TOPCon structure,where they exhibit a synergistic effect.Notably,when combined at an optimal ratio of 1%deuterium oxide(D2O),this mixture significantly enhances passivation performance compared to the individual addition of hydrogen or deuterium.Specifically,it results in an approximate 15 mV increase in the implied open-circuit voltage(iVOC)for doublesided passivated samples,achieving an average iVOC value of 734 mV.The mechanisms underlying the enhancement in passivation can be inferred,suggesting that deuterium forms stronger bonds with silicon than hydrogen,effectively passivating interfaces and neutralizing defects within polycrystalline silicon(poly-Si).In the presence of dangling bonds on the poly-Si surface,the presence of H2O molecules expands the range of silicon atoms in the vicinity of the contact site where electrons are exchanged or reacted with D2O both horizontally and vertically,demonstrating enhanced adsorption capacity.Proof-of-concept TOPCon solar cells using this novel deuteration/hydrogenation hybrid strategy achieve a promising efficiency of 23.19%,accompanied by substantial improvements in electrical performance,thereby highlighting the exceptional potential of deuterium passivation for high-efficiency TOPCon solar cells.展开更多
The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic chemistry.For this purpose,many efficient deuterium labeling method...The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic chemistry.For this purpose,many efficient deuterium labeling methodologies have been developed,including hydrogen isotope exchange(HIE),reductive deuteration,and dehalogenative deuteration that allow for the synthesis of selectively deuterated compounds.In the last few years,great breakthroughs in selective isotope labeling have been achieved and the interest in new methodologies for the deuteration of organic molecules is rising.In this review,we summarized the recent developments in the selective deuteration of organic molecules since 2021.Several types of key processes in deuterium incorporation reactions,including H/D exchange,reductive deuteration and dehalogenative deuteration,are introduced and discussed.展开更多
Hydrogenation/deuteration of carbon chloride(C–Cl)bonds is of high significance but remains a remarkable challenge in synthetic chemistry,especially using safe and inexpensive hydrogen donors.In this article,a visibl...Hydrogenation/deuteration of carbon chloride(C–Cl)bonds is of high significance but remains a remarkable challenge in synthetic chemistry,especially using safe and inexpensive hydrogen donors.In this article,a visible-light-photocatalytic watersplitting hydrogenation technology(WSHT)is proposed to in-situ generate active H-species(i.e.,Had)for controllable hydrogenation of aryl chlorides instead of using flammable H2.When applying heavy water-splitting systems,we could selectively install deuterium at the C–Cl position of aryl chlorides under mild conditions for the sustainable synthesis of high-valued added deuterated chemicals.Sub-micrometer Pd nanosheets(Pd NSs)decorated crystallined polymeric carbon nitrides(CPCN)is developed as the bifunctional photocatalyst,whereas Pd NSs not only serve as a cocatalyst of CPCN to generate and stabilize H(D)-species but also play a significant role in the sequential activation and hydrogenation/deuteration of C–Cl bonds.This article highlights a photocatalytic-WSHT for controllable hydrogenation/deuteration of low-cost aryl chlorides,providing a promising way for the photosynthesis of high-valued added chemicals instead of the hydrogen evolution.展开更多
Deuterated compounds are valuable in synthetic,pharmaceutical,and analytical chemistry.The deuteration of halides is a widespread method for highly site-selective deuterium installation.However,the facile,efficient,an...Deuterated compounds are valuable in synthetic,pharmaceutical,and analytical chemistry.The deuteration of halides is a widespread method for highly site-selective deuterium installation.However,the facile,efficient,and economical deuterium incorporation remains challenging.In this work,we introduced a practical deuteration of(hetero)aryl halides through an electrochemical reduction method.This transformation proceeded smoothly at room temperature without metal catalysts,external reductants,or toxic or dangerous reagents.Remarkably,low-cost and chemically equivalent D2O was the sole deuterium source in this reaction.Professional electrosynthesis equipment was not essential because we demonstrated common batteries and electrodes were enough for this reaction.展开更多
We report herein a visible light-mediated direct deuteration of alkenes with D_(2)O or deuterated methanol(MeOD)using a cobaloxime as a hydrogen/deuterium(H/D)exchange catalyst.The synergistic photoredox/Co catalysis ...We report herein a visible light-mediated direct deuteration of alkenes with D_(2)O or deuterated methanol(MeOD)using a cobaloxime as a hydrogen/deuterium(H/D)exchange catalyst.The synergistic photoredox/Co catalysis enabled facile deuterium(D)-incorporation of a variety of terminal and internal alkenes at either terminal or benzylic positions.We proposed that this process proceeded through a sequence of reversible addition-elimination reactions and fast proton exchange involving Co(III)–H,which was generated in situ by photoreduction.展开更多
Deuterium labelling possesses wide applications in pharmaceuticals,chemical science and materials science.Development of efficient methodologies for the synthesis of deuterium labelled compounds,especially hydrogen is...Deuterium labelling possesses wide applications in pharmaceuticals,chemical science and materials science.Development of efficient methodologies for the synthesis of deuterium labelled compounds,especially hydrogen isotope exchange(HIE),continued to receive an impressive attention over the years.Herein,we developed a nitrogen doped nano-scale nickel catalyst for deuterium incorporation of a variety of nitrogen heterocycles using D_(2)O as the isotope source.The usefulness of this approach has been demonstrated by 10 g-scale for complex pharmaceuticals.This methodology represents a practical and scalable deuteration and the air-and water-stable nanocatalyst enables efficient labelling in a straightforward manner.展开更多
Deuterium labelling techniques have shown widespread applications in organic synthesis,analytic chemistry,life science and material science.The design of practical deuteration reactions which is environmentally friend...Deuterium labelling techniques have shown widespread applications in organic synthesis,analytic chemistry,life science and material science.The design of practical deuteration reactions which is environmentally friendly is highly desired for pharmaceutical development and industrial processes while remaining underexplored.We herein report a convenient,transition metal-free strategy for reductive deuteration of ketone derivatives toα-deuterated alcohols by employing a conjugated aryl amine-based organophotocatalyst,a dipropyl disulfide cocatalyst and an inorganic reductant.Upon irradiation with visible light and under an air atmosphere,a variety of diaryl ketones,heteroaryl ketones,cyclic ketones,α-ketoesters,benzil derivatives,aliphatic ketones and drug-like molecules were converted into correspondingα-deuterated aryl alcohols in good to excellent yields and with high deuterium incorporation(up to 99%D-incorporation).Only low toxic side-products,such as sodium salts and carbon dioxide,were generated.Consequently,the synthetic utility of this method is highlighted by the preparation of several D-labeled drug-like molecules,including orphenadrine,carbinoxamine and modafinil.展开更多
Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and part...Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and particularly,it is non-poisonable chemical.In this paper,we use DC to replace ultra-dry chloroform(UC)as the processing solvent for preparation of active layers of organic solar cells.First,we selected PM6:BTP-e C9 as the basic binary and counted 100 solar cells'data,from which comparable device performance were obtained with use of DC and UC.Interestingly,DC showed better reproducibility,superior storage under a nitrogen atmosphere and a little better performance than UC.Both DC and UC gave rise of comparable hole and electron mobilities and similar charge recombination losses.Second,we based PM6:Y6 and D18-Cl:Y6 as the binaries and similar effects were obtained from both UC and DC when counting 30 devices for each binary.Third,the universality of the use of DC for preparing highefficient OSCs were again checked with several binary and ternary systems.In all,this study demonstrate that DC can replace UC for use in the field of OSCs.展开更多
The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in...The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in the Saxi deposit remain poorly understood.This study employs in situ U-Pb dating of apatite from the altered granite,along with trace element and S-Pb isotopic analysis of arsenopyrite,to investigate the timing,source of ore-forming fluids and the mechanisms of tungsten enrichment.The apatite in the altered granite yields a U-Pb age of 147.0±4.0 Ma,indicating magmatic activity during the Early Cretaceous.Three generations of arsenopyrite(Apy)are identified:Apy-1 in the altered granite,Apy-2 in the pegmatite dikes and Apy-3 in the quartz veins.The S/Fe ratios for Apy-1,Apy-2 and Apy-3 range from 0.98 to 1.09,0.89 to 0.92 and 0.86 to 1.02,respectively(average 0.97),suggesting a magmatic-hydrothermal origin.Sulfur isotope values(δ^(34)S=4.29‰-8.11‰)indicate that it was likely sourced from deep magmatic-hydrothermal fluids.Lead isotopic compositions of arsenopyrite suggest that the granitic parental magma is derived from the upper crust.These findings point to a magmatic-hydrothermal origin for the vein-type tungsten mineralization,linked to a concealed magmatichydrothermal system in the Early Cretaceous.展开更多
A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxalin...A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxaline using H2O as the hydrogen source with 80%Faradaic efficiency and the reverse dehydrogenation of hydrogen-rich 1,2,3,4-tetrahydroquinoxaline with up to 99%yield and selectivity.The in situ generated active hydrogen atom(H^(*))is plausibly involved in the hydrogenation of quinoxaline,where a consecutive hydrogen radical coupled electron transfer pathway is proposed.Notably,the MoNi_(4)alloy exhibits efficient quinoxaline hydrogenation at an overpotential of only 50 mV,owing to its superior water dissociation ability to provide H^(*)in alkaline media.In situ Raman tests indicate that the Ni^(Ⅱ)/Ni^(Ⅲ)redox couple can promote the dehydrogenation process,representing a promising anodic alternative to low-value oxygen evolution.Impressively,electrocatalytic deuteration is easily achieved with up to 99%deuteration ratios using D2O.This method is capable of producing a series of functionalized hydrogenated and deuterated quinoxalines.展开更多
Infrared spectrum is a general quantitation method which can be used to determine the concentration of a certain component in mixture.We proposed that it could also be used to determine the coreactant level of a react...Infrared spectrum is a general quantitation method which can be used to determine the concentration of a certain component in mixture.We proposed that it could also be used to determine the coreactant level of a reactive system.A two-part polyurethane film was used as a model system.The results showed that the height ratio of ring mode signal in urea and C—O signal in polyester polyol can be used to calculate the ratio of the two reactants.The assignments of the peaks were studied by in-situ reaction monitoring with moisture level changes and deuteration methods.The applicable conditions of this calibration curves were also discussed.展开更多
基金Financial support from Science and Technology Innovation Program of Hunan Province(No.2022RC4044)。
文摘Deuterium(D),a stable and non-radioactive isotope of hydro-gen,is naturally present in the environment and is distinguishedfrom hydrogen by its greater mass.This mass difference resultsin a reduced stretching frequency of the carbon-deuterium(C-D)bond,leading to lower ground state energy and higher bond dis-sociation energy compared to the carbon-hydrogen(C–H)bond.
文摘Amines represent fundamental motifs in various chemical contexts and are widely used in agrochemicals and pharmaceuticals.The development of earth-abundant metal-based heterogeneous catalysts for the synthesis amines remains an important goal in terms of chemical research and industrial application/manufacture.Herein,we developed an efficient and highly selective nitrogen-doped nickel catalyst enriched with Lewis acid sites,which has been applied for to the hydrogenative coupling of nitriles and amines with molecular hydrogen for the synthesis of a train of functionalised and structurally diverse secondary and tertiary amines.Furthermore,catalytic hydrogenation and deuteration of nitriles were achieved under milder conditions,yielding a series of primary amines and deuterated amines with high deuterium incorporation.
基金financially supported by the National Natural Science Foundation of China (Nos. 11504231 and 31630002)the Innovation Program of Shanghai Municipal Education Commission
文摘Protein internal dynamics is essential for its function. Exploring the internal dynamics of protein molecules as well as its connection to protein structure and function is a central topic in biophysics. However, the atomic motions in protein molecules exhibit a great degree of complexities. These complexities arise from the complex chemical composition and superposition of different types of atomic motions on the similar time scales, and render it challenging to explicitly understand the microscopic mechanism governing protein motions, functions, and their connections. Here, we demonstrate that, by using neutron scattering, molecular dynamics simulation, and deuteration technique, one can address this challenge to a large extent.
基金supported by the Natural Science Foundation of Shaanxi Province(No.2020JQ-141)the National Natural Science Foundation of China(No.22005245)+1 种基金the Synergy Innovation Foundation of the University and Enterprise for Graduate Students in Northwestern Polytechnical University(No.CX2021037)the National Key Research and Development Program of China(No.SQ2021YFE010191)。
文摘Deuterated ethylene is an important building block for manufacturing various deuterated polyolefins and chemicals.However,low-cost and large-scale production of deuterated ethylene still remain a great challenge.Herein,with D_(2)O as the D source,we first propose an electrocatalytic deuteration strategy for continuous production of deuterated ethylene from acetylene under ambient conditions.Specially,Ag nanoparticles exhibit a very high deuterated ethylene Faradic efficiency of up to 99.3%at-0.6 V vs.reversible hydrogen electrode.Meanwhile,Ag nanoparticles achieve a deuterated ethylene production rate of 3.72×10^(3)mmol h^(-1)g^(-1)cat and an excellent long-term stability with deuterated ethylene Faradaic efficiencies of~95%in a two-electrode flow cell,which substantially outperform state-of-the-art values for previously reported deuterated alkenes.In-situ electrochemical Infrared absorption and Raman spectroscopies reveal superior acetylene absorption and formation of deuterated ethylene on Ag nanoparticles.This efficient electrocatalytic deuteration strategy opens a new window for continuous and economic production of deuterated alkenes.
基金Project supported by the National Natural Science Foundation of China(Grant No.51402173)Shandong Provincial Natural Science Joint Foundation with Universities and Scientific Research Institution,China(Grant No.ZR2017LEM006)+1 种基金the Neutron Physics Laboratory,China Academy of Engineering Physics(Grant No.2014BB07)the Fundamental Research Funds for Central Universities,China(Grant No.FRF-TP-15-099A1)
文摘A series of deuterated ammonium dihydrogen phosphate(DADP) crystals were grown and their structures were investigated by using powder neutron diffraction method. In the entire composition range, the deuterated level in the crystals is lower compared with the aqueous growth solution. The deuterium segregation coefficient in the crystals decreases with increasing deuterium content of the solution. The deuterium content in the NH_(4)^(+) group is higher than that in H_(2)PO_(4)^(-) group.In addition, the variations of lattice parameters are shown here.
基金financially supported by the National Natural Science Foundation of China (Nos. 21875035 and 21991144)。
文摘Deuteration of hydrogen-bonded phase transition crystals can increase the transition temperatures due to the isotope effect. But rare examples show the opposite trend that originates from the structural changes of the hydrogen bond, known as the geometric H/D isotope effect. Herein, we report an organic crystal, diethylammonium hydrogen 1,4-terephthalate, exhibits a reversible structural phase transition and dielectric switching. Structural study shows the cations reside in channels formed by one-dimensional hydrogen-bonded anionic chains and undergo an order-disorder transition at around 206 K. The deuterated counterpart shows an elongation of the O…O hydrogen bond by about 0.005 A. This geometric isotope effect releases the internal pressure of the anionic host on the cation vips and results in a downward shift of the phase transition temperature by 10 K.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51323002 and 51402173the Independent Innovation Foundation of Shandong University under Grant No 2012JC016+1 种基金the Natural Science Foundation for Distinguished Young Scholar of Shandong Province under Grant No JQ201218the Project of Key Laboratory of Neutron Physics of China Academy Of Engineering Physics under Grant No 2014BB07
文摘Conductivity measurements of deuterated ammonium dihydrogen phosphate （DADP） crystals with different deuterated degrees are described. The conductivities increase with the deuterium content, and the value of the a-direction is larger than that of the e-direction. Compared with DKDP crystals, DADP crystals have larger conductivities, which is partly due to the existence of A defects. The ac conductivity over the temperature range 25-170℃has shown a knee in the curve ofln（σT） versus T-1. The conductivity activation energy calculated by the slope of the high temperature region decreases with the deuterium content. The previously reported phase transition is not seen.
基金supported by the Singapore National Research Foundation Investigatorship(A-8002259-00-00 and NRF-NRFI09-0021)Tan Chin Tuan Centennial Professorship(E-467-00-0012-02).
文摘Organic host-vip systems exhibiting room-temperature phosphorescence(RTP)hold great promise for sensing,encryption,and bioimaging.However,achieving both long lifetimes and high efficiency remains challenging,as enhanced spin-orbit coupling(SOC)often competes with efficient intersystem crossing(ISC).We report an isotope-engineering strategy that overcomes the lifetime-efficiency trade-off in classical carbazole(Cz)host-vip systems.Doping just 0.5 wt%of deuterated 1H-benzo[f]indole(BdD8)into Cz extends the RTP lifetime from 0.485 to 1.771 s,a 3.65-fold enhancement without compromising the phosphorescence quantum yield.Replacing the N-H group in BdD8 with a CD3 moiety(BdD8CD3)and using a methylated host(CzCH3)further extends the RTP lifetime to 1.870 s.This improvement arises from isotope-induced suppression of non-radiative decay and enhancement of ISC,as evidenced by a reduction in the non-radiative rate from 2.01 to 0.51 s^(-1) and an increase in the ISC rate from 4.91×10^(7) s^(-1) to 6.21×10^(7) s^(-1).Building on this success,we applied the strategy to benzo[b]carbazole(BCz)derivatives,which similarly exhibited enhanced RTP performance.Finally,we demonstrate time-resolved multi-information encoding enabled by this ultralong afterglow system.
基金support by the National Key Research and Development Program of China(grant nos.2021YFA1500100,2022YFA1503200,and 2022YFA1502900)the National Natural Science Foundation of China(grant nos.22193013,21933007,and 22088102)+1 种基金the Strategic Priority Research Programof the Chinese Academy of Science(grant no.XDB17000000)New Cornerstone Science Foundation.
文摘Developing green and practical D-labeling techniques is valuable and in high demand for medical chemistry,mechanistic studies,and materials science.Although dearomatic deuteration of simple aromatic systems represents an attractive protocol to access D-labeled compounds,the inherent chemical stability of(het)aromatics leaves successful examples rather scarce.Different from transition metal catalysis,which involves dangerous and expensive deuterium sources,and harsh reaction conditions,represented herein is the first electrophotocatalytic platform for dearomative deuteration of inert(het)arenes.Taking economical D_(2)O as the deuterium source and organic N,N-bis(2,6-diisopropylphenyl)perylene-3,4,9,10-bis(dicarboximide)as the electrophotocatalyst,Birch-type deuteration of(het)aromatics is realized with excellent site-selectivity,good functional group compatibility,and high D-incorporation.Late-stage deuteration of complex pharmaceuticals and gram-scale scale-up are easily implemented.This methodology overcomes existing synthetic challenges,and no overreduction reaction occurs.Moreover,the electrophotocatalytic platform works well with renewable solar-to-electricity,offering an effective way to prepare synthetically useful deuterated molecules.
基金the National Key Research and Development Program of China(No.2022YFB4200201)Natural Science Foundation of Tianjin(Nos.23JCYBJC01620,22JCYBJC01300)+3 种基金the National Natural Science Foundation of China(Nos.62074084,62274098)the project of highefficiency heterojunction solar cell technology and equipment industrialization(TC220A04A-159)111 Project(B16027)the Fundamental Research Funds for the Central Universities,Nankai University(Nos.63241573,63241568).
文摘The advent of the passivating contact concept and its accelerated development have propelled crystalline silicon(c-Si)solar cells into a new era,establishing them as a driving force behind the latest breakthroughs in photovoltaic(PV)conversion efficiency.The continual refinement of passivation performance is pivotal to the fabrication of high-efficiency devices.Here,we report a novel deuteration/hydrogenation hybrid strategy involving the deliberate incorporation of deuterium(D,2H)via atmosphere annealing to neutralize defects and enhance the passivation performance of tunnel oxide passivating contact(TOPCon)solar cells.Our findings reveal that hydrogen and deuterium can coexist within the TOPCon structure,where they exhibit a synergistic effect.Notably,when combined at an optimal ratio of 1%deuterium oxide(D2O),this mixture significantly enhances passivation performance compared to the individual addition of hydrogen or deuterium.Specifically,it results in an approximate 15 mV increase in the implied open-circuit voltage(iVOC)for doublesided passivated samples,achieving an average iVOC value of 734 mV.The mechanisms underlying the enhancement in passivation can be inferred,suggesting that deuterium forms stronger bonds with silicon than hydrogen,effectively passivating interfaces and neutralizing defects within polycrystalline silicon(poly-Si).In the presence of dangling bonds on the poly-Si surface,the presence of H2O molecules expands the range of silicon atoms in the vicinity of the contact site where electrons are exchanged or reacted with D2O both horizontally and vertically,demonstrating enhanced adsorption capacity.Proof-of-concept TOPCon solar cells using this novel deuteration/hydrogenation hybrid strategy achieve a promising efficiency of 23.19%,accompanied by substantial improvements in electrical performance,thereby highlighting the exceptional potential of deuterium passivation for high-efficiency TOPCon solar cells.
基金the National Key R&D Program of China(No.2021YFA1500100,A.L.)National Natural Science Foundation of China(22031008,A.L.+1 种基金212200007,W.L.)Science Foundation of Wuhan(2020010601012192,A.L.).
文摘The deuteration of organic compounds has attracted more attentions in recent years for the potential applications in new drug discovery and synthetic chemistry.For this purpose,many efficient deuterium labeling methodologies have been developed,including hydrogen isotope exchange(HIE),reductive deuteration,and dehalogenative deuteration that allow for the synthesis of selectively deuterated compounds.In the last few years,great breakthroughs in selective isotope labeling have been achieved and the interest in new methodologies for the deuteration of organic molecules is rising.In this review,we summarized the recent developments in the selective deuteration of organic molecules since 2021.Several types of key processes in deuterium incorporation reactions,including H/D exchange,reductive deuteration and dehalogenative deuteration,are introduced and discussed.
基金supported by the National Natural Science Foundation of China(21972094,51701127,21401190)China Postdoctoral Science Foundation(2017M612709)+5 种基金Guangdong Special Support ProgramPengcheng Scholar ProgramShenzhen Peacock Plan(KQJSCX20170727100802505,KQTD2016053112042971)Educational Commission of Guangdong Province(2016KTSCX126)Foundation for Distinguished Young Talents in Higher Education of Guangdong(2018KQNCX221)Shenzhen Innovation Program(JCYJ20170818142642395).
文摘Hydrogenation/deuteration of carbon chloride(C–Cl)bonds is of high significance but remains a remarkable challenge in synthetic chemistry,especially using safe and inexpensive hydrogen donors.In this article,a visible-light-photocatalytic watersplitting hydrogenation technology(WSHT)is proposed to in-situ generate active H-species(i.e.,Had)for controllable hydrogenation of aryl chlorides instead of using flammable H2.When applying heavy water-splitting systems,we could selectively install deuterium at the C–Cl position of aryl chlorides under mild conditions for the sustainable synthesis of high-valued added deuterated chemicals.Sub-micrometer Pd nanosheets(Pd NSs)decorated crystallined polymeric carbon nitrides(CPCN)is developed as the bifunctional photocatalyst,whereas Pd NSs not only serve as a cocatalyst of CPCN to generate and stabilize H(D)-species but also play a significant role in the sequential activation and hydrogenation/deuteration of C–Cl bonds.This article highlights a photocatalytic-WSHT for controllable hydrogenation/deuteration of low-cost aryl chlorides,providing a promising way for the photosynthesis of high-valued added chemicals instead of the hydrogen evolution.
基金supported by the National Natural Science Foundation of China(no.21520102003)the Hubei Province Natural Science Foundation of China(no.2017CFA010)The Program of Introducing Talents of Discipline to Universities of China(111 Program)is also appreciated.
文摘Deuterated compounds are valuable in synthetic,pharmaceutical,and analytical chemistry.The deuteration of halides is a widespread method for highly site-selective deuterium installation.However,the facile,efficient,and economical deuterium incorporation remains challenging.In this work,we introduced a practical deuteration of(hetero)aryl halides through an electrochemical reduction method.This transformation proceeded smoothly at room temperature without metal catalysts,external reductants,or toxic or dangerous reagents.Remarkably,low-cost and chemically equivalent D2O was the sole deuterium source in this reaction.Professional electrosynthesis equipment was not essential because we demonstrated common batteries and electrodes were enough for this reaction.
基金the Natural Science Foundation of China(grant nos.91956000,22031006,21861132003),Tsinghua University Initiative Scientific Research Program,and Haihe Laboratory of Sustainable Chemical Transformations for financial support.
文摘We report herein a visible light-mediated direct deuteration of alkenes with D_(2)O or deuterated methanol(MeOD)using a cobaloxime as a hydrogen/deuterium(H/D)exchange catalyst.The synergistic photoredox/Co catalysis enabled facile deuterium(D)-incorporation of a variety of terminal and internal alkenes at either terminal or benzylic positions.We proposed that this process proceeded through a sequence of reversible addition-elimination reactions and fast proton exchange involving Co(III)–H,which was generated in situ by photoreduction.
基金support from the National Key R&D Program of China(No.2021YFA1500100,A.L.)National Natural Science Foundation of China(22031008,A.L.+1 种基金212200007,W.L.)Science Foundation of Wuhan(2020010601012192,A.L.).
文摘Deuterium labelling possesses wide applications in pharmaceuticals,chemical science and materials science.Development of efficient methodologies for the synthesis of deuterium labelled compounds,especially hydrogen isotope exchange(HIE),continued to receive an impressive attention over the years.Herein,we developed a nitrogen doped nano-scale nickel catalyst for deuterium incorporation of a variety of nitrogen heterocycles using D_(2)O as the isotope source.The usefulness of this approach has been demonstrated by 10 g-scale for complex pharmaceuticals.This methodology represents a practical and scalable deuteration and the air-and water-stable nanocatalyst enables efficient labelling in a straightforward manner.
基金support from the National Natural Science Foundation of China(Nos.22071209 and 22071206)the national youth talent support program,and the Fundamental Research Funds for the Central Universities(No.20720190048).
文摘Deuterium labelling techniques have shown widespread applications in organic synthesis,analytic chemistry,life science and material science.The design of practical deuteration reactions which is environmentally friendly is highly desired for pharmaceutical development and industrial processes while remaining underexplored.We herein report a convenient,transition metal-free strategy for reductive deuteration of ketone derivatives toα-deuterated alcohols by employing a conjugated aryl amine-based organophotocatalyst,a dipropyl disulfide cocatalyst and an inorganic reductant.Upon irradiation with visible light and under an air atmosphere,a variety of diaryl ketones,heteroaryl ketones,cyclic ketones,α-ketoesters,benzil derivatives,aliphatic ketones and drug-like molecules were converted into correspondingα-deuterated aryl alcohols in good to excellent yields and with high deuterium incorporation(up to 99%D-incorporation).Only low toxic side-products,such as sodium salts and carbon dioxide,were generated.Consequently,the synthetic utility of this method is highlighted by the preparation of several D-labeled drug-like molecules,including orphenadrine,carbinoxamine and modafinil.
基金the financial supports from the Department of Science and Technology of Inner Mongolia Autonomous Region(No.2020GG0192)the Natural Science Foundation of Inner Mongolia Autonomous Region(No.2022ZD04)Inner Mongolia Normal University。
文摘Chloroform is a common and excellent solvent for preparing high-efficient organic solar cells(OSCs),however,it is toxic and poisonable chemical.In comparisons,deuterated chloroform(DC)is less toxic and costly,and particularly,it is non-poisonable chemical.In this paper,we use DC to replace ultra-dry chloroform(UC)as the processing solvent for preparation of active layers of organic solar cells.First,we selected PM6:BTP-e C9 as the basic binary and counted 100 solar cells'data,from which comparable device performance were obtained with use of DC and UC.Interestingly,DC showed better reproducibility,superior storage under a nitrogen atmosphere and a little better performance than UC.Both DC and UC gave rise of comparable hole and electron mobilities and similar charge recombination losses.Second,we based PM6:Y6 and D18-Cl:Y6 as the binaries and similar effects were obtained from both UC and DC when counting 30 devices for each binary.Third,the universality of the use of DC for preparing highefficient OSCs were again checked with several binary and ternary systems.In all,this study demonstrate that DC can replace UC for use in the field of OSCs.
基金Yunnan Major Scientific and Technological Project(grant no.202202AG050006)National Natural Science Foundation project(grant No.42272078)Yunnan Fundamental Research Project(grant No.202401CF070094).
文摘The Saxi tungsten deposit,located in the Laojunshan ore district of southeastern Yunnan Province,is a significant W-polymetallic deposit.The origins of tungstenbearing pegmatite dikes and quartz vein mineralization in the Saxi deposit remain poorly understood.This study employs in situ U-Pb dating of apatite from the altered granite,along with trace element and S-Pb isotopic analysis of arsenopyrite,to investigate the timing,source of ore-forming fluids and the mechanisms of tungsten enrichment.The apatite in the altered granite yields a U-Pb age of 147.0±4.0 Ma,indicating magmatic activity during the Early Cretaceous.Three generations of arsenopyrite(Apy)are identified:Apy-1 in the altered granite,Apy-2 in the pegmatite dikes and Apy-3 in the quartz veins.The S/Fe ratios for Apy-1,Apy-2 and Apy-3 range from 0.98 to 1.09,0.89 to 0.92 and 0.86 to 1.02,respectively(average 0.97),suggesting a magmatic-hydrothermal origin.Sulfur isotope values(δ^(34)S=4.29‰-8.11‰)indicate that it was likely sourced from deep magmatic-hydrothermal fluids.Lead isotopic compositions of arsenopyrite suggest that the granitic parental magma is derived from the upper crust.These findings point to a magmatic-hydrothermal origin for the vein-type tungsten mineralization,linked to a concealed magmatichydrothermal system in the Early Cretaceous.
文摘A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxaline using H2O as the hydrogen source with 80%Faradaic efficiency and the reverse dehydrogenation of hydrogen-rich 1,2,3,4-tetrahydroquinoxaline with up to 99%yield and selectivity.The in situ generated active hydrogen atom(H^(*))is plausibly involved in the hydrogenation of quinoxaline,where a consecutive hydrogen radical coupled electron transfer pathway is proposed.Notably,the MoNi_(4)alloy exhibits efficient quinoxaline hydrogenation at an overpotential of only 50 mV,owing to its superior water dissociation ability to provide H^(*)in alkaline media.In situ Raman tests indicate that the Ni^(Ⅱ)/Ni^(Ⅲ)redox couple can promote the dehydrogenation process,representing a promising anodic alternative to low-value oxygen evolution.Impressively,electrocatalytic deuteration is easily achieved with up to 99%deuteration ratios using D2O.This method is capable of producing a series of functionalized hydrogenated and deuterated quinoxalines.
文摘Infrared spectrum is a general quantitation method which can be used to determine the concentration of a certain component in mixture.We proposed that it could also be used to determine the coreactant level of a reactive system.A two-part polyurethane film was used as a model system.The results showed that the height ratio of ring mode signal in urea and C—O signal in polyester polyol can be used to calculate the ratio of the two reactants.The assignments of the peaks were studied by in-situ reaction monitoring with moisture level changes and deuteration methods.The applicable conditions of this calibration curves were also discussed.
