Self-trapping excitons(STEs) emission in metal halides has been a matter of interest, correlating with the strength of electron-phonon coupling in the lattice, which are usually caused by ions with ns~2 electronic str...Self-trapping excitons(STEs) emission in metal halides has been a matter of interest, correlating with the strength of electron-phonon coupling in the lattice, which are usually caused by ions with ns~2 electronic structure. In this work, Sb^(3+)/Te^(4+)ions doped Zn-based halide single crystals(SCs) with two STEs emissions have been synthesized and the possibility of its anti-counterfeiting application was explored.Further, the relationship between the strength of electron-phonon coupling and photoluminescence quantum yields(PLQYs) for STEs in a series of metal halides has been studied. And the semi-empirical range of the Huang-Rhys factors(S) for metal halides with excellent photoluminescence(PL) property has been summarized. This work provides ideas for further research into the relationship between luminescence performance and electron-phonon coupling of metal halides, and also provides a reference for designing the metal halides with high PLQYs.展开更多
Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated wi...Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.展开更多
Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of...Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of polyfluoroarenes with alkyl halides under mild conditions is reported.Polyfluoroarenes(3~6 F)can reacted smoothly with a diverse range of alkyl halides,such as primary,secondary,and tertiary alkyl iodides.The efficient formation of C(sp2)—C(sp3)can be achieved through the combination of Ni catalysis and(Bpin)2/K2CO3 as terminal reductant.展开更多
Existing organic halide synthesis routes typically employ elemental halogens(X_(2),X=Cl or Br),leading to low atom economy and significant environmental pollution.In this work,we developed an atom efficient electrosyn...Existing organic halide synthesis routes typically employ elemental halogens(X_(2),X=Cl or Br),leading to low atom economy and significant environmental pollution.In this work,we developed an atom efficient electrosynthesis and separation strategy for halogenation reagents—N-chlorosuccinimide(NCS)and N-bromosuccinimide(NBS)—at high current densities.Faradic efficiency(FE)of 91.0%and 81.3%was achieved for NCS and NBS generation on RuO_(x)/TiO_(2)/Ti in a batch cell,respectively.Electrosynthesis of NCS likely involves both heterogeneous catalytic and homogeneous tandem pathways,while NBS is likely formed in a Langmuir-Hinshelwood mechanism with a proton-coupled electron transfer as the rate-determining step.A coupled continuous electrocatalytic synthesis and in situ separation setup was developed for the efficient production of NCS and NBS,which yielded 0.77 g of NCS in 12000 s and 0.81 g of NBS in 15000 s,both with relative purity exceeding 95%.The halogenation of acetone using NCS and NBS enabled gram-scale production of the key intermediate in organic synthesis,1-halogenacetone,with over 95%recovery of succinimide.展开更多
The crystallization of ionic crystals has traditionally been explained by Gibbs's classical nucleation theory.However,recent observations of intermediate phases during nucleation suggest that the process may be mo...The crystallization of ionic crystals has traditionally been explained by Gibbs's classical nucleation theory.However,recent observations of intermediate phases during nucleation suggest that the process may be more complex,necessitating new theoretical frameworks,though key empirical evidence remains elusive.In this study,we used microdroplets to investigate the crystallization of sodium halides(NaCl,NaBr,and NaI)under homogeneous nucleation conditions across a wide range of supersaturations.In the evaporating droplet,NaCl follows the classical nucleation pathway,whereas NaBr and NaI exhibit the formation of an intermediate phase prior to the nucleation of anhydrous and hydrous single crystals,respectively.Optical and computational analyses indicate that these intermediate phases are liquid crystal phases composed of contact ion pairs.These findings establish a new theoretical framework for crystal nucleation and growth and offer methods to control nucleation pathways,enabling us to achieve desired crystals regardless of specific conditions.展开更多
Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. ...Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. Here,the emission intensity of(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6) was strengthened between 9.3 GPa and 17.2 GPa, accompanied by the redshift of emission wavelength. The photoluminescence(PL) of Cu(Ⅰ)-based organometallic halides originates from multiple emission states, which are a metal-to-ligand charge transfer or a halide-to-ligand charge transfer(MLCT/HLCT)excited state and a cluster-centered(CC) excited state. MLCT/HLCT-related emission wavelength redshifts while CCrelated emission wavelength remains unchanged, indicating that the rearrangement of different emission states plays a critical role in the changes of luminescence wavelength. This study not only deepens the understanding of the influence of high pressure on(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6), but also provides valuable insights into the structure–property relationship of zero-dimensional Cu(Ⅰ)-based organometallic halides.展开更多
Low-dimensional lead-free metal halides have emerged as promising candidates for anti-counterfeiting applications,characterized by their low toxicity,diverse crystal structures,and exceptional optical properties.Conve...Low-dimensional lead-free metal halides have emerged as promising candidates for anti-counterfeiting applications,characterized by their low toxicity,diverse crystal structures,and exceptional optical properties.Conventional anti-counterfeiting technologies based on low-dimensional metal halides are often constrained by complex and time-consuming heating and solvent treatments that may insufficiently modify the luminescent characteristics of emitters,thus hindering their practical implementation in effective anti-counterfeiting strategies.In this study,we employ an innovative alloying strategy in low-dimensional zinc halides Cs_(2)ZnCl_(4) to enhance their luminescent performance.By introducing self-trapped exciton(STE)states through the alloying of Cu^(+)and Sb^(3+)ions in Cs_(2)ZnCl_(4),we achieve bright blue and red photoluminescence(PL)centered at 492 nm and 744 nm,respectively,under 266 nm excitation,with only red emission observed under 365 nm excitation.This approach enables instant and reliable anti-counterfeiting applications.This work presents new opportunities for developing robust anti-counterfeiting and information encryption/decryption technologies.展开更多
The demand for neodymium(NdFeB) permanent magnets for electric vehicles and eco-friendly generators is increasing.However,NdFeB magnets contain rare earth elements(REEs),which are limited in supply.In this study,we pe...The demand for neodymium(NdFeB) permanent magnets for electric vehicles and eco-friendly generators is increasing.However,NdFeB magnets contain rare earth elements(REEs),which are limited in supply.In this study,we performed an exchange reaction between magnesium halides(fluoride and chloride) and waste NdFeB scrap and then compared the characteristics of the extracted halides salts.The compositions of the ternary Mg fluoride(LiF:NaF:MgF_(2)=50:40:10 in mole ratio) and chloride(LiCl:NaCl:MgCl_(2)=10:50:40 in mole ratio) salts were thermodynamically determined for achieving low eutectic temperatures.The reactions between the NdFeB scrap powder(1-2 mm) and Mg halide salts were carried out at 1073 and 873 K for the fluoride and chloride systems,respectively,in an argon atmosphere.After the reaction,we separated Nd halide from the residual salt and evaluated the Ndextraction rate.The phase formation of the salt was analyzed using X-ray diffraction(XRD),and the extraction rate of Nd was analyzed using inductively coupled plasma optical emission spectroscopy(ICPOES).Nd was extracted in the form of Nd halide(NdF_(3) or NdCl_(3)),and the extraction rates in the fluoride and chloride systems are 98.64% and 84.59%,respectively.Thus,the fluoride system is more effective than the chloride system for Nd extraction.Our study provides a comprehensive comparative analysis of the effectiveness of fluo ride and chlo ride systems in extracting REEs from NdFeB magnet scrap.Our study findings can be used to develop an effective method for recycling magnet scraps.展开更多
The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benz...The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.展开更多
10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-...10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-deficient functional groups can be well tolerated under this mild reaction conditions.展开更多
The development of deep-red emitting lead-free metal-halide perovskites with high photoluminescence quantum yields (PLQYs) and outstanding stability remains a major challenge for displays and deep-tissue bioimaging.In...The development of deep-red emitting lead-free metal-halide perovskites with high photoluminescence quantum yields (PLQYs) and outstanding stability remains a major challenge for displays and deep-tissue bioimaging.In this work,we report a facile and convenient solvothermal method to synthesize metal halides Cs_(2)Zn X_(4)(X=Cl,Br) that however is PL innert at room temperature.Upon composition engineering utilizing Sn^(2+) as the dopant,the resulting Cs_(2)Zn Cl_(4):Sn not only emits strong deep-red PL peaked at700 nm with the highest 99.4%PLQY among the similar materials so far,but also exhibits excellent structure stability in air (PLQY remains 96%after one year exposure to the atmosphere).Detailed experimental characterizations and theoretical calculations reveal that the deep-red emission stems from self-trapped excitons induced by the Sn^(2+) dopant.Particularly,triplet emission (^(3)P_(2)→^(1)S_(0)) from Sn-5s^(2) orbitals has been observed at low temperature due to the break of parity-forbidden transition.This work provides an important guidance for the development of deep-red light-emitting materials with low price,high efficiency and excellent stability.展开更多
The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation pr...The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.展开更多
A convenient, efficient, one-pot, novel process has been developed for the synthesis of carbamates from corresponding alkyl halides and amines using basic resin/CO2 system.
The photoinduced reactions of aryl halides with carbazolyl nitrogen anion,in dimethyl sulfoxide,yield the corresponding N-arylated products.These reactions are suggested in terms of the S;Nl mechaism of nucleophilic s...The photoinduced reactions of aryl halides with carbazolyl nitrogen anion,in dimethyl sulfoxide,yield the corresponding N-arylated products.These reactions are suggested in terms of the S;Nl mechaism of nucleophilic substitution.展开更多
A theoretical study of the thermal decomposition kinetics of ethane halides（C2H6-nXn（n = 1～3）;X = F,Cl,Br） has been carried out at the B3LYP/6-31＋＋G＊＊ and B3PW91/631＋＋G＊＊ levels of theory.Among these meth...A theoretical study of the thermal decomposition kinetics of ethane halides（C2H6-nXn（n = 1～3）;X = F,Cl,Br） has been carried out at the B3LYP/6-31＋＋G＊＊ and B3PW91/631＋＋G＊＊ levels of theory.Among these methods and comparison of activation parameters with available experimental values,the B3PW91/6-31＋＋G＊＊ method is in good agreement with the experimental data.The analysis of bond order and natural bond orbital（NBO） charges,bond indexes,and synchronicity parameters suggest the elimination of HX in reactions 1～9（HF：compounds 1～3,HCl：compounds 4～6,and HBr：compounds 7～9） occur through a concerted and slightly asynchronous four-membered cyclic transition state type of mechanism.展开更多
Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carb...Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carbon supports. XPS and IR-spectroscopy data show the formation of rhodium chalcogen halides in solids prepared by different methods. We have found that the productivity of acetic acid by carbon supported rhodium chalcogen halides depends strongly on the carbon carrier and the method of the catalyst preparation. Namely, the catalyst with highest productivity for the acetic acid is prepared by synthesizing the rhodium chalcogen halide over the carbon support followed by thermal destruction. We have also found that rhodium chalcogen halides over activated carbons are more active compared with fullerene supported catalysts.展开更多
Photopromoted carbonylation of alkyl halides with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts. Our preliminary work sh...Photopromoted carbonylation of alkyl halides with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts. Our preliminary work showed that alkyl halides can be transformed into alkene and alkane directly under irradiation, but the esters can not be transformed. It is assumed that the carbonylation of alkyl halides may be proceeded in two ways.展开更多
The IR spectroscopic data indicate the tautomeric transformations of typical aprotonic organic fluids such as methane halides with gross formulas CHX3 （X = Cl, Br）, CH2X2 （X = CI, Br, I） and CCl4 at normal conditi...The IR spectroscopic data indicate the tautomeric transformations of typical aprotonic organic fluids such as methane halides with gross formulas CHX3 （X = Cl, Br）, CH2X2 （X = CI, Br, I） and CCl4 at normal conditions. These transformations lead to the appearance in molecules of activated hydrogen atoms similar in the spectral behaviour to the bounded proton. The classical analysis of IR bands in 5000-600 cm^-1 region, for studied samples and their deuterated derivatives, proves the existence in the presented organic fluids of hydrogen and dihydrogen bonds. This bonding promotes the formation of supramolecular structure in methane halides. The mechanism of unusual binding in liquid phase in terms of common knowledge for the basic chemical properties of the examined compounds is discussed.展开更多
Four novel palladium（（Ⅱ）） complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reactio...Four novel palladium（（Ⅱ）） complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of awl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd（OAc）2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis展开更多
The potassium salts of thiocarboxanilide of 2- phenylimino-3-phenyl-4-thiazolidinone and 1,3- diphenyl-2-thioxo-4-imidazolone react with hydrazonoyl halides in N,N-dimethylformamide to afford the corresponding 1,3,4-t...The potassium salts of thiocarboxanilide of 2- phenylimino-3-phenyl-4-thiazolidinone and 1,3- diphenyl-2-thioxo-4-imidazolone react with hydrazonoyl halides in N,N-dimethylformamide to afford the corresponding 1,3,4-thiadiazoline derivatives. 2-Phenylimino-3-phenyl-4-thiazolidinone reacts with active chloromethylene compounds in N,N-dimethylformamide to give the corresponding thiazolylidenethiazolidin-4-one derivatives. The new compounds were characterized using IR, 1H NMR, 13C NMR and mass spectra.展开更多
基金supported by the financial aid from the National Natural Science Foundation of China (No. 22271273)International Partnership Program of Chinese Academy of Sciences (No. 121522KYSB20190022)。
文摘Self-trapping excitons(STEs) emission in metal halides has been a matter of interest, correlating with the strength of electron-phonon coupling in the lattice, which are usually caused by ions with ns~2 electronic structure. In this work, Sb^(3+)/Te^(4+)ions doped Zn-based halide single crystals(SCs) with two STEs emissions have been synthesized and the possibility of its anti-counterfeiting application was explored.Further, the relationship between the strength of electron-phonon coupling and photoluminescence quantum yields(PLQYs) for STEs in a series of metal halides has been studied. And the semi-empirical range of the Huang-Rhys factors(S) for metal halides with excellent photoluminescence(PL) property has been summarized. This work provides ideas for further research into the relationship between luminescence performance and electron-phonon coupling of metal halides, and also provides a reference for designing the metal halides with high PLQYs.
基金supported by the National Natural Science Foundation of China(22278066,21776039)the National Key R&D Program of China(2023YFB4103001)The Fundamental Research Funds for the Central Universities(DUT2021TB03).
文摘Mercury removal from coal combustion flue gas remains a significant challenge for environmental protection due to the lack of cost-effective sorbents.In this study,a series of red mud(RM)-based sorbents impregnated with sodium halides(NaBr and NaI)are presented to capture elemental mercury(Hg^(0))from flue gas.The modified RM underwent comprehensive characterization,including analysis of its textural qualities,crystal structure,chemical composition,and thermal properties.The results indicate that the halide impregnation substantially impacts the surface area and pore size of the RM.Hg^(0) removal performance was evaluated on a fixed-bed reactor in simulated flue gas(consisting of N_(2),O_(2),CO_(2),NO and SO_(2),etc.)on a modified RM.At an optimal adsorption temperature of 160℃,NaI-modified sorbent(RMI5)offers a removal efficiency of 98%in a mixture of gas,including O_(2),NO and HCl.Furthermore,pseudo-second-order model fitting results demonstrate the chemisorption mechanism for the adsorption of Hg^(0) in kinetic investigations.
文摘Polyfluoroarenes represent an essential group of compounds in the fields of medical and material chemistry.It is still a challenge to synthesize alkylated polyfluoroarenes.Herein,a Ni-catalyzed reductive alkylation of polyfluoroarenes with alkyl halides under mild conditions is reported.Polyfluoroarenes(3~6 F)can reacted smoothly with a diverse range of alkyl halides,such as primary,secondary,and tertiary alkyl iodides.The efficient formation of C(sp2)—C(sp3)can be achieved through the combination of Ni catalysis and(Bpin)2/K2CO3 as terminal reductant.
文摘Existing organic halide synthesis routes typically employ elemental halogens(X_(2),X=Cl or Br),leading to low atom economy and significant environmental pollution.In this work,we developed an atom efficient electrosynthesis and separation strategy for halogenation reagents—N-chlorosuccinimide(NCS)and N-bromosuccinimide(NBS)—at high current densities.Faradic efficiency(FE)of 91.0%and 81.3%was achieved for NCS and NBS generation on RuO_(x)/TiO_(2)/Ti in a batch cell,respectively.Electrosynthesis of NCS likely involves both heterogeneous catalytic and homogeneous tandem pathways,while NBS is likely formed in a Langmuir-Hinshelwood mechanism with a proton-coupled electron transfer as the rate-determining step.A coupled continuous electrocatalytic synthesis and in situ separation setup was developed for the efficient production of NCS and NBS,which yielded 0.77 g of NCS in 12000 s and 0.81 g of NBS in 15000 s,both with relative purity exceeding 95%.The halogenation of acetone using NCS and NBS enabled gram-scale production of the key intermediate in organic synthesis,1-halogenacetone,with over 95%recovery of succinimide.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1C1C2006535)supported by the Korea Basic Science Institute(National Research Facilities and Equipment Center)grant funded by the Korea government(MSIT)(No.RS-2024-00403164)supported by the National Research Foundation of Korea grant funded by the Korea government,Ministry of Science and ICT(Development of Nanofiber Yarn Based Compound Sensor as a Comprehensive Wearable Healthcare Solution)(Grant No.RS-2024-00357296).
文摘The crystallization of ionic crystals has traditionally been explained by Gibbs's classical nucleation theory.However,recent observations of intermediate phases during nucleation suggest that the process may be more complex,necessitating new theoretical frameworks,though key empirical evidence remains elusive.In this study,we used microdroplets to investigate the crystallization of sodium halides(NaCl,NaBr,and NaI)under homogeneous nucleation conditions across a wide range of supersaturations.In the evaporating droplet,NaCl follows the classical nucleation pathway,whereas NaBr and NaI exhibit the formation of an intermediate phase prior to the nucleation of anhydrous and hydrous single crystals,respectively.Optical and computational analyses indicate that these intermediate phases are liquid crystal phases composed of contact ion pairs.These findings establish a new theoretical framework for crystal nucleation and growth and offer methods to control nucleation pathways,enabling us to achieve desired crystals regardless of specific conditions.
基金Project supported by the National Key R&D Program of China (Grant No. 2023YFA1406200)the National Natural Science Foundation of China (Grant Nos. 12174144 and 12474009)the Graduate Innovation Fund of Jilin University (Grant No. 2024CX201)。
文摘Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. Here,the emission intensity of(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6) was strengthened between 9.3 GPa and 17.2 GPa, accompanied by the redshift of emission wavelength. The photoluminescence(PL) of Cu(Ⅰ)-based organometallic halides originates from multiple emission states, which are a metal-to-ligand charge transfer or a halide-to-ligand charge transfer(MLCT/HLCT)excited state and a cluster-centered(CC) excited state. MLCT/HLCT-related emission wavelength redshifts while CCrelated emission wavelength remains unchanged, indicating that the rearrangement of different emission states plays a critical role in the changes of luminescence wavelength. This study not only deepens the understanding of the influence of high pressure on(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6), but also provides valuable insights into the structure–property relationship of zero-dimensional Cu(Ⅰ)-based organometallic halides.
基金supported by Chongqing Natural Science Foundation Innovation and Development Joint Fund(CSTB2025NSCQ-LZX0001)Ongoing Research Funding Program,(ORF-2025-762)King Saud University,Riyadh,Saudi Arabia,National Natural Science Foundationof China(11974063).
文摘Low-dimensional lead-free metal halides have emerged as promising candidates for anti-counterfeiting applications,characterized by their low toxicity,diverse crystal structures,and exceptional optical properties.Conventional anti-counterfeiting technologies based on low-dimensional metal halides are often constrained by complex and time-consuming heating and solvent treatments that may insufficiently modify the luminescent characteristics of emitters,thus hindering their practical implementation in effective anti-counterfeiting strategies.In this study,we employ an innovative alloying strategy in low-dimensional zinc halides Cs_(2)ZnCl_(4) to enhance their luminescent performance.By introducing self-trapped exciton(STE)states through the alloying of Cu^(+)and Sb^(3+)ions in Cs_(2)ZnCl_(4),we achieve bright blue and red photoluminescence(PL)centered at 492 nm and 744 nm,respectively,under 266 nm excitation,with only red emission observed under 365 nm excitation.This approach enables instant and reliable anti-counterfeiting applications.This work presents new opportunities for developing robust anti-counterfeiting and information encryption/decryption technologies.
基金supported by the Technology Innovation (20010817,Technology for the ecofriendly rare earth refining from used motors and manufacture of permanent magnet materials) funded by the Ministry of Trade,Industry & Energy (MOTIE),Korea。
文摘The demand for neodymium(NdFeB) permanent magnets for electric vehicles and eco-friendly generators is increasing.However,NdFeB magnets contain rare earth elements(REEs),which are limited in supply.In this study,we performed an exchange reaction between magnesium halides(fluoride and chloride) and waste NdFeB scrap and then compared the characteristics of the extracted halides salts.The compositions of the ternary Mg fluoride(LiF:NaF:MgF_(2)=50:40:10 in mole ratio) and chloride(LiCl:NaCl:MgCl_(2)=10:50:40 in mole ratio) salts were thermodynamically determined for achieving low eutectic temperatures.The reactions between the NdFeB scrap powder(1-2 mm) and Mg halide salts were carried out at 1073 and 873 K for the fluoride and chloride systems,respectively,in an argon atmosphere.After the reaction,we separated Nd halide from the residual salt and evaluated the Ndextraction rate.The phase formation of the salt was analyzed using X-ray diffraction(XRD),and the extraction rate of Nd was analyzed using inductively coupled plasma optical emission spectroscopy(ICPOES).Nd was extracted in the form of Nd halide(NdF_(3) or NdCl_(3)),and the extraction rates in the fluoride and chloride systems are 98.64% and 84.59%,respectively.Thus,the fluoride system is more effective than the chloride system for Nd extraction.Our study provides a comprehensive comparative analysis of the effectiveness of fluo ride and chlo ride systems in extracting REEs from NdFeB magnet scrap.Our study findings can be used to develop an effective method for recycling magnet scraps.
文摘The polymerization behaviors of Styrene (St) in the presence of CuX/L [X=Cl or Br; L= 2,2 bipyridine (bpy), 1,10 phenanthroline (phen) or 4,7 diphenyl 1,10 phenanthroline (DPP) ] and R X (R=trichloromethyl, benzyl or allyl; X=Cl or Br) have been studied and examined. In a CuCl/bpy/RCl/St system, a bimodal GPC peak at the early stage of polymerization was observed, and a concept of multi active species was proposed to explain this phenomenon. In a CuCl/phen (DPP)/RCl/St system, the \%M\%\-n of polystyrene (PS) increased linearly with St conversion and ln[M] o/[M] also increased linearly with time, indicating the living nature of this system. Furthermore, the stability of the propagating active species in a CuBr/phen/RBr/St system is higher than that in the CuBr/phen/RBr/St system.
基金supported by the National Natural Science Foundation of China (No.21102036)Plan for Scientific Innovation Talent of Henan University of Technology (No.11CXRC02)startup fund from HAUT (No.2010BS042)
文摘10 mol% Cul combined with the DMEDA ligand can efficiently catalyze the N-arylation of 2-arylindoles with aryl iodides and aryl bromides in good to excellent yields. The aryl halides bearing electron-rich or electron-deficient functional groups can be well tolerated under this mild reaction conditions.
基金the financial supports from National Natural Science Foundation of China (Nos. 91741105, 22109130)Chongqing Municipal Natural Science Foundation (Nos. cstc2018jcyj AX0625, cstc2021jcyj-msxm X1180)Program for Innovation Team Building at Institutions of Higher Education in Chongqing (No. CXTDX201601011)。
文摘The development of deep-red emitting lead-free metal-halide perovskites with high photoluminescence quantum yields (PLQYs) and outstanding stability remains a major challenge for displays and deep-tissue bioimaging.In this work,we report a facile and convenient solvothermal method to synthesize metal halides Cs_(2)Zn X_(4)(X=Cl,Br) that however is PL innert at room temperature.Upon composition engineering utilizing Sn^(2+) as the dopant,the resulting Cs_(2)Zn Cl_(4):Sn not only emits strong deep-red PL peaked at700 nm with the highest 99.4%PLQY among the similar materials so far,but also exhibits excellent structure stability in air (PLQY remains 96%after one year exposure to the atmosphere).Detailed experimental characterizations and theoretical calculations reveal that the deep-red emission stems from self-trapped excitons induced by the Sn^(2+) dopant.Particularly,triplet emission (^(3)P_(2)→^(1)S_(0)) from Sn-5s^(2) orbitals has been observed at low temperature due to the break of parity-forbidden transition.This work provides an important guidance for the development of deep-red light-emitting materials with low price,high efficiency and excellent stability.
文摘The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.
文摘A convenient, efficient, one-pot, novel process has been developed for the synthesis of carbamates from corresponding alkyl halides and amines using basic resin/CO2 system.
文摘The photoinduced reactions of aryl halides with carbazolyl nitrogen anion,in dimethyl sulfoxide,yield the corresponding N-arylated products.These reactions are suggested in terms of the S;Nl mechaism of nucleophilic substitution.
文摘A theoretical study of the thermal decomposition kinetics of ethane halides（C2H6-nXn（n = 1～3）;X = F,Cl,Br） has been carried out at the B3LYP/6-31＋＋G＊＊ and B3PW91/631＋＋G＊＊ levels of theory.Among these methods and comparison of activation parameters with available experimental values,the B3PW91/6-31＋＋G＊＊ method is in good agreement with the experimental data.The analysis of bond order and natural bond orbital（NBO） charges,bond indexes,and synchronicity parameters suggest the elimination of HX in reactions 1～9（HF：compounds 1～3,HCl：compounds 4～6,and HBr：compounds 7～9） occur through a concerted and slightly asynchronous four-membered cyclic transition state type of mechanism.
文摘Gas phase carbonylation of methane is studied in the presence of molecular oxygen over pure carbon carriers and carbon supported rhodium chalcogen halides. Activated carbons and fullerene blacks have been used as carbon supports. XPS and IR-spectroscopy data show the formation of rhodium chalcogen halides in solids prepared by different methods. We have found that the productivity of acetic acid by carbon supported rhodium chalcogen halides depends strongly on the carbon carrier and the method of the catalyst preparation. Namely, the catalyst with highest productivity for the acetic acid is prepared by synthesizing the rhodium chalcogen halide over the carbon support followed by thermal destruction. We have also found that rhodium chalcogen halides over activated carbons are more active compared with fullerene supported catalysts.
基金We are indebted to the National Natural Science Foundations of China(No.20172010,20242004),for the generous financial support
文摘Photopromoted carbonylation of alkyl halides with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts. Our preliminary work showed that alkyl halides can be transformed into alkene and alkane directly under irradiation, but the esters can not be transformed. It is assumed that the carbonylation of alkyl halides may be proceeded in two ways.
文摘The IR spectroscopic data indicate the tautomeric transformations of typical aprotonic organic fluids such as methane halides with gross formulas CHX3 （X = Cl, Br）, CH2X2 （X = CI, Br, I） and CCl4 at normal conditions. These transformations lead to the appearance in molecules of activated hydrogen atoms similar in the spectral behaviour to the bounded proton. The classical analysis of IR bands in 5000-600 cm^-1 region, for studied samples and their deuterated derivatives, proves the existence in the presented organic fluids of hydrogen and dihydrogen bonds. This bonding promotes the formation of supramolecular structure in methane halides. The mechanism of unusual binding in liquid phase in terms of common knowledge for the basic chemical properties of the examined compounds is discussed.
基金Financial support from Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(No. 2015157)Teaching Reform Project of Shanxi Normal University(No. SD2014JGKT-52)Undergraduate Training Programs for Innovation and Entrepreneurship of Modern College of Arts and Sciences, Shanxi Normal University(No. WL2015CXCY-YJ-26)
文摘Four novel palladium（（Ⅱ）） complexes coordinated by phosphorus atoms from both 3,5-disubstituted-1H- 1,2,4-diazaphospholes in monodentate fashion were developed as efficient catalyst for the Mizoroki- Heck reaction of aryl halides with electron-deficient olefins. The coupling reaction of awl halide bearig different functional groups with olefin derivatives took place and the corresponding products were isolated in good to excellent yields under optimal conditions. The procedure exhibits good functional group tolerance and wide substrate scope. This Mizoroki-Heck reaction was further achieved using Pd（OAc）2 and 3,5-di-isopropyl-1H-1,2,4-diazaphospholes as combined catalyst, which provide the convenient and alternative method in organic synthesis
文摘The potassium salts of thiocarboxanilide of 2- phenylimino-3-phenyl-4-thiazolidinone and 1,3- diphenyl-2-thioxo-4-imidazolone react with hydrazonoyl halides in N,N-dimethylformamide to afford the corresponding 1,3,4-thiadiazoline derivatives. 2-Phenylimino-3-phenyl-4-thiazolidinone reacts with active chloromethylene compounds in N,N-dimethylformamide to give the corresponding thiazolylidenethiazolidin-4-one derivatives. The new compounds were characterized using IR, 1H NMR, 13C NMR and mass spectra.
