Fluoroalkene and 1,2-enedichalcogenide represent two classes of valuable structures with wide applications, yet methods for their direct integration remain unknown. Herein, we report a dehalogenative 1,2-dichalcogenat...Fluoroalkene and 1,2-enedichalcogenide represent two classes of valuable structures with wide applications, yet methods for their direct integration remain unknown. Herein, we report a dehalogenative 1,2-dichalcogenation reaction of internal fluoroalkyl alkenes and readily available disulfides, thiols, or diselenides for the synthesis of diverse fluoroalkenyl 1,2-enedichalcogenides. Multiple carbon-halogen bonds in perfluoroalkyl-containing alkenyl iodides can be selectively cleaved under mild and transition-metal-free conditions. This protocol features a broad substrate scope, good scalability, and the ability to modify complex molecules. Mechanistic studies revealed that the key step in the reaction is the formation of a reactive fluoroallene, which is readily attacked by nucleophilic thiolate anions to achieve an unconventional defluorinative chalcogenation.展开更多
Aluminum batteries are attractive in electrochemical energy storage due to high energy density and lowcost aluminum,while the energy density is limited for the lack of favorable positive electrode materials to match a...Aluminum batteries are attractive in electrochemical energy storage due to high energy density and lowcost aluminum,while the energy density is limited for the lack of favorable positive electrode materials to match aluminum negative electrodes.Tellurium positive electrode is intrinsically electrically conductive among chalcogen and holds high theoretical specific capacity(1260.27 mAh g^(-1)) and discharge voltage plateau(~1,5 V).However,the chemical and electrochemical dissolution of Te active materials results in the low material utilization and poor cycling stability.To enhance the electrochemical performance,herein a nitrogen doped porous carbon(N-PC) is derived from zeolite imidazolate framework(ZIF-67)as an effective tellurium host to suppress the undesired shuttle effect.In order to inhibit the volume expansion of N-PC during the charge/discharge process,the reduced graphene oxide(rGO) nanosheets are introduced to form a stable host materials(N-PC-rGO) for stabilizing Te.The physical encapsulation and chemical confinement to soluble tellurium species are achieved.N-PC-rGO-Te positive electrode exhibits an improved initial specific capacity and long-term cycling performance at a current density of 500 mA g^(-1)(initial specific capacity:935.5 mAh g^(-1);after 150 cycles:467.5 mAh g^(-1)), highlighting a promising design strategy for inhibiting chemical and electrochemical dissolution of Te.展开更多
The electroactive materials used in the counter electrode(CE)are of great concern as they influence the photovoltaic performances of dye-sensitized solar cells.The main functions of CE materials are collecting electro...The electroactive materials used in the counter electrode(CE)are of great concern as they influence the photovoltaic performances of dye-sensitized solar cells.The main functions of CE materials are collecting electrons from the external circuit and transferring them to the electrolyte and realizing the catalytic reduction of the redox species(I3^– or Co^3+)present in the electrolyte.The research hotspot of CE materials is seeking functional materials that display high efficiency,low cost,and good electrochemical stability and can substitute the benchmark platinum electrode.Chalcogen compounds of cobalt,nickel,and iron have been widely applied as CE materials and exhibit excellent electrocatalytic performances owing to their unique electrical properties,similar energies of adsorption of I atoms as platinum,excellent catalytic activities,and good chemical stabilities.In this review,we trace the developments and performances of chalcogen compounds of iron,cobalt,and nickel as CE materials and present the latest research directions for improving the electrocatalytic performances.We then highlight the optimization strategies for further improving their performances,such as fabrication of architectures,regulation of the components,synthesis of composites containing carbon materials,and elemental doping.展开更多
Chalcogenative sulfones(thiosulfonates and selenosulfonates), as reactants for organic transformations,are widely used and interesting because of their potential to react with nucleophiles, electrophiles, and free rad...Chalcogenative sulfones(thiosulfonates and selenosulfonates), as reactants for organic transformations,are widely used and interesting because of their potential to react with nucleophiles, electrophiles, and free radicals. As stable radical reagents, the synthesis and applications of chalcogenative sulfones have opened up a novel pathway to synthesize many kinds of compounds containing sulfur or selenium motifs. However, despite the numerous recent works on the synthesis and applications of thiosulfonates and selenosulfonates as radical reagents, no review has yet provided a summary of the literature. In this paper, we aim to review the synthesis and applications strategies of chalcogenative sulfones as radical reagents reported over the past several decades. Different types of catalysis are discussed in this review:(i) metal catalysis;(ii) visible-light catalysis;(iii) synergistic catalysis;and(iiii) other types. Concurrently,in visible-light catalysis and metallaphotoredox catalysis sections, we highlight that developing relatively environmentally friendly synthetic methods in this area is always a great challenge, but also a persistent pursuit. Finally, the scopes, limitations, mechanisms, and existing problems of some reactions are described briefly.展开更多
Using ethylene glycol as solvent and reductant, CuCl2-2H2O, （NH2）2CS and self-prepared GaCl3 as the starting materials, CuGaS2 nanostrucutures were synthesized on a large scale at 220℃. Powder X-ray diffraction. tr...Using ethylene glycol as solvent and reductant, CuCl2-2H2O, （NH2）2CS and self-prepared GaCl3 as the starting materials, CuGaS2 nanostrucutures were synthesized on a large scale at 220℃. Powder X-ray diffraction. transmission electron microscopy, field-emission scanning electron microscope, high-resolution transmission electron microscopy＂ and X-ray＂ photoelectron spectroscopy were used to characterize the products. It demonstrated the evolution of the CuGaS2 particles from spherical assemblies to flowerlike morphology, over time, at 220℃. Simultaneously, we elucidated the specific roles of reaction temperature, reaction time and solvent in the formation of the final CuGaS2 nanostructures. A possible formation mechanism of CuGaS2 nanostrucutures was also discussed. The room temperature photoluminescence spectrum showed blue-shift and an increase of intensity, with a decrease in the sizes of CuGaS2 particles.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
We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band struc...We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, Tl2ZrTe3 and Tl2HfTe3 can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second-order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications(ZT ~ 0.9).展开更多
Artificial membrane transporters that either use chalcogen bonds to facilitate transmembrane flux of anions or show high selectivity toward perchlorate anions are rare.In this work,we report on one such novel monopept...Artificial membrane transporters that either use chalcogen bonds to facilitate transmembrane flux of anions or show high selectivity toward perchlorate anions are rare.In this work,we report on one such novel monopeptide-based transporter system,featuring both chalcogen bonds for highly efficient anion transport and high transport selectivity toward ClO_(4)^(-) anions.Structurally,these monopeptide molecules associate with each other via H-bonds to produce H-bonded 1D stack that not only one dimensionally but also directionally aligns the terminal bicyclic thiophene motifs to the same side.Functionally,these well-aligned thiophenes create a sulfur-rich transmembrane pathway,combinatorially fine-tunable to enable anions to efficiently cross the membrane in the increasing activity of Cl^(-)<Br^(-)<NO_(3)^(-)<ClO_(4)^(-) via chalcogen bonds,with EC_(50)values of 0.75,0.40,0.37 and 0.093μmol/L(0.3 mol%relative to lipid molecules),respectively.展开更多
Increasing risks of incidental and occupational exposures to two-dimensional transition metal dichalcogenides(2D TMDCs)due to their broad application in various areas raised their public health concerns.While the comp...Increasing risks of incidental and occupational exposures to two-dimensional transition metal dichalcogenides(2D TMDCs)due to their broad application in various areas raised their public health concerns.While the composition-dependent cytotoxicity of 2D TMDCs has been well-recognized,how the outer chalcogenide atoms and inner transition metal atoms differentially contribute to their perturbation on cell homeostasis at non-lethal doses remains to be identified.In the present work,we compared the autophagy induction and related mechanisms in response to WS_(2),NbS_(2),WSe_(2)and Nb Se_(2)nanosheets exposures in MH-S murine alveolar macrophages.All these 2D TMDCs had comparable physicochemical properties,overall cytotoxicity and capability in triggering autophagy in MH-S cells,but showed outer chalcogen-dependent subcellular localization and activation of autophagy pathways.Specifically,WS_(2)and NbS_(2)nanosheets adhered on the cell surface and internalized in the lysosomes,and triggered m TOR-dependent activation of autophagy.Meanwhile,WSe_(2)and Nb Se_(2)nanosheets had extensive distribution in cytoplasm of MH-S cells and induced autophagy in an m TOR-independent manner.Furthermore,the 2D TMDCs-induced perturbation on autophagy aggravated the cytotoxicity of respirable benzo[a]pyrene.These findings provide a deeper insight into the potential health risk of environmental 2D TMDCs from the perspective of homeostasis perturbation.展开更多
The in-situ generated oxyanions at electrochemically reconstructed catalysts from metal-based nonoxide compounds have been proven to significantly accelerate oxygen evolution reaction(OER)kinetics.However,it remains a...The in-situ generated oxyanions at electrochemically reconstructed catalysts from metal-based nonoxide compounds have been proven to significantly accelerate oxygen evolution reaction(OER)kinetics.However,it remains a challenge to retain these self-released oxyanions at reconstructed catalysts,hindering its utilization as a tool to develop efficient OER catalysts.Here,we demonstrate a versatile selftransformed carbonate regulation strategy to efficiently retain the self-released chalcogenate at Co oxyhydroxides reconstructed from carbon-incorporated Co selenides under OER conditions.These selftransformed CO_(3)^(2-)can induce electron accumulation and narrow d bond at Co sites to facilitate the Co3d-O 2p orbital hybridization between Co sites and SeO_(x)^(2-)for enhanced SeO_(x)^(2-)retention,which can accelerate the rate-limiting step for^(*)OOH formation during OER.Relative to CoOOH-SeO_(x)^(2-)with limited SeO_(x)^(2-)residues,CoOOH-CO_(3)^(2-)/SeO_(x)^(2-)with elevated SeO_(x)^(2-)retention by CO_(3)^(2-)regulation exhibited a 5.6-fold increase in current density and a remarkable lower Tafel slope towards OER.This strategy paves a rational avenue to design efficient catalysts for electrooxidation reactions through finely regulating self-released oxyanions at reconstructed structures.展开更多
Strategic active site organization is imperative for the advancement of effective and long-lasting catalysts of oxygen reduction reactions.However,the controllable multi-active site design is a highly intricate topic ...Strategic active site organization is imperative for the advancement of effective and long-lasting catalysts of oxygen reduction reactions.However,the controllable multi-active site design is a highly intricate topic for catalyst synthesis.Employing pre-trapping and post-activation strategy,Fe-N bonding structure and S,Se functionalized heteroatom are integrated into a conductive porous carbon.In this process,the nitrogen-abundant polymer 1,3,5-triformylbenzene-tris(4-aminophenyl)benzene(Tf-TAPA)adsorbs Fe^(3+)under the intrinsically metal anchoring ability of N atoms and simultaneously in-situ assembles longchain thiophene-S.Subsequently,the Fe^(3+)is transformed into Fe-N_(x)moieties with the conversion of the organic chain to incompletely graphitized carbon.Furthermore,the alteration of the electronic configuration achieved through the introduction of dual-atom S and Se leads to a pronounced enhancement in catalytic efficiency.Benefitting from the Fe-N_(x)bonding structure,dense structural defects,and conductive carbon networks,the resultant Fe-S,Se/NCNs possesses a positive half-wave potential of 0.86 V and a 90%current retention rate,outstripping the Pt/C benchmark.Moreover,the liquid and flexible ZAB driven by Fe-S,Se/NCNs achieves large power densities of 259.7 and 164.7 m W/cm^(2),respectively.This study provides a new comprehension in developing an efficient and stable M-N-C oxygen electrocatalyst.展开更多
The gas phase methane oxidative carbonylation was studied in the presence of molecular oxygen over silica materials including their mechanical mixtures with rhodium chalcogen chlorides obtained in non-aqueous inorgani...The gas phase methane oxidative carbonylation was studied in the presence of molecular oxygen over silica materials including their mechanical mixtures with rhodium chalcogen chlorides obtained in non-aqueous inorganic media. The formation of Rh4SCl7, Rh4S9Cl2, Rh4SesCl3 and Rh3Se3Cl solids was confirmed by elemental analysis, IR absorption spectroscopy, XPS and X-ray diffraction. Silica, vanadium-, and molybdenum-containing mesoporous molecular sieves have been used as supports. It was found that productivity of oxygenates （methanol, methyl acetate and acetic acid） depends mainly on the method of the catalyst preparation and the type of the support.展开更多
The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into...The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.展开更多
This paper presents a versatile method for synthesizing electron-rich polynuclear transition metal clusters with chalcogen bridges and phosphine ligands.The reactions of transition metal complexes(R3P)2MX2(M=Co,Ni;R=P...This paper presents a versatile method for synthesizing electron-rich polynuclear transition metal clusters with chalcogen bridges and phosphine ligands.The reactions of transition metal complexes(R3P)2MX2(M=Co,Ni;R=Ph,Bu,Et;X=Cl,Br) with bridging reagents Na2Ex (E=S,Se;x=1.2) are described.The geometric and electronic structures of a series of polynuclear transition metal clusters with trianglar M3 units are also discussed.展开更多
Growing interest in non-covalent interactions involving chalcogen atoms has been ascribed to their importance in crystal engineering, molecular recognition and macromolecular edifices. The present study is dealing wit...Growing interest in non-covalent interactions involving chalcogen atoms has been ascribed to their importance in crystal engineering, molecular recognition and macromolecular edifices. The present study is dealing with chalcogen bonds involving divalent Sulphur, Selenium and Tellurium atoms, acting as sigma-hole donors, in small-molecule compounds using the Cambridge Structural Database (CSD) in conjunction with ab initio calculations. Results derived from CSD surveys and computational study revealed that nucleophiles formed complexes with the chalcogen-bond donors R1-X-R2 (X = S, Se or Te). The main forces stabilizing the complexes were chalcogen bonds, enhanced by dispersion interactions. Complexation pattern and energetics show that nucleophile bonding at divalent S, Se and Te atoms is a relatively strong and directed interaction. The bond consists of a charge transfer from a nucleophile atom lone pair to an X-R1 or X-R2 antibonding orbital.展开更多
Photocatalytic CO_(2)reduction and conversion into fuel or high-value-added chemicals are expected to solve environmental and energy problems such as fossil fuel depletion and global warming.Efficient electron transpo...Photocatalytic CO_(2)reduction and conversion into fuel or high-value-added chemicals are expected to solve environmental and energy problems such as fossil fuel depletion and global warming.Efficient electron transport between the photosensitizer and the catalyst is crucial for improving the photocatalytic effect.Herein,mononuclear rhenium(I)tethered selenoviologen(HOOC-SeV-Re)was covalently linked to the surface of amine-polyethylene glycol(PEG)-protected black phosphorus quantum dots(BPQDs@PEG)via amide bonds,forming the heterojunction BPQDs@PEG-SeV-Re.The heterojunction features a high specific surface area,broad-spectrum absorption,and efficient staggered gap catalysis.The integration of selenoviologen not only enhances visible light excitation but also suppresses electron-hole recombination,thereby fostering the formation of radical states and facilitating two consecutive intramolecular electron transfer processes.This selfphotosensitized system produces CO with a rapid generation rate(41.48 mmol·h^(−1)·g^(−1)),high turnover number(428.0),and CO selectivity(exceeded 99%).Additionally,Pd-catalytic carbonylation reactions were combined with photocatalytic CO_(2)reduction to produce molecular drugs and functional polymers using a two-chamber reactor,which supplied a new strategy for the conversion and utilization of CO_(2).展开更多
Luminescent lanthanide cerium(III) compounds have gathered increasing research interest in both inorganic phosphors and functional molecular complexes. Cerium(III) exhibits broad double-peak emission originating from ...Luminescent lanthanide cerium(III) compounds have gathered increasing research interest in both inorganic phosphors and functional molecular complexes. Cerium(III) exhibits broad double-peak emission originating from 5d excited state 2D3/2 to 4f ground states 2F7/2 and 2F5/2. It is vital to adjust the bandwidth of the emission for different applications like lighting and display, while no regulation between these two peaks in Ce(III) emitters has been reported hitherto. In this work, novel heavy-atom-induced narrow emission is observed in luminescent Ce(III) complexes by adopting imidodiphosphinate ligand with different chalcogen-coordinating sites from O to S, Se, and Te. Not only a new Ce(III) complex with orange–red emission beyond the traditional emission color regions of Ce(III) was obtained, but also the ratio of the two peaks was systematically tuned to achieve the narrowest emission from Ce(III) with a full width at half maximum of 42 nm. Time-dependent density functional theory calculations ascribe the tuning of emission spectra to centroid shift and simultaneously provide the orbital contribution values of different chalcogen atoms to the emission excited state. By extending the coordination atoms from classic oxygen and nitrogen to heavier and softer elements, these results give new insight into luminescence properties and mechanisms of Ce(III) emission.展开更多
Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazoliu...Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazolium-based olefin scaffolds,wherein intramolecular through-space n→π^(*)orbital interaction plays a stabilizing role in the Z isomer approaching quantitative conversion.The manipulation of diverse noncovalent interactions,including intermolecular chalcogen bonding,further provided versatile handles for regulating molecular recognition and multiaddressable switching.Despite bidirectional E/Z photoisomerization with neutral tellurazole derivatives,protonation-induced cationic tellurazoliums allowed significant enhancement in the efficiency of Z→E switching(E up to 73%)while maintaining high percentage E→Z switching(Z up to 95%),as chalcogen bonding with counteranions contributes to the stabilization of electron-accepting tellurazoliums affording a larger wavelength difference between E/Z isomers.Furthermore,the n→π^(*)orbital interaction enables the preference of Z isomer in the ground state for N-methyl tellurazoliums.Bidirectional E/Z photoswitching with high conversion(Z up to 99%,E up to 81%)was attained,and E→Z isomerization can also be invoked by nucleophilic catalysis,making N-methyl tellurazoliums as T-type photoswitches.The results showcase the power of noncovalent interactions for controlling molecular photoswitches and should set the scene for vip recognition,dynamic assemblies,and responsive materials.展开更多
Cross-coupling reactions between aryl halides and thiolates or selenolates typically require transition metals,photocatalysts,strong bases,or/and malodorous thiols/selenols,with various mechanisms proposed.This study ...Cross-coupling reactions between aryl halides and thiolates or selenolates typically require transition metals,photocatalysts,strong bases,or/and malodorous thiols/selenols,with various mechanisms proposed.This study aims to leverage a new application of neutral ChB to address these challenges and enable a very simple photoinduced cross-electrophile C—S/Se coupling using readily available chalcogen electrophiles.Mechanistic investigations have revealed the important role of neutral ChB in facilitating single electron transfer processes,thereby enabling the generation of thiolates/selenolates from stable chalcogen electrophiles andα-aminoalkyl radicals,which possess the capability to abstract halogen atoms from aryl iodides.Moreover,the study provided support for the radical nucleophilic substitution mechanism.展开更多
基金the financial support from Natural Science Foundation of Gansu Province(25JRRF004)Jiangsu Provincial University Key Laboratory of Intelligent Medical Sensing Materials and Devicesthe Postgraduate Research&Practice Innovation Program of Jiangsu Province(No.KYCX25_1703,recipient:C.Zhang).
文摘Fluoroalkene and 1,2-enedichalcogenide represent two classes of valuable structures with wide applications, yet methods for their direct integration remain unknown. Herein, we report a dehalogenative 1,2-dichalcogenation reaction of internal fluoroalkyl alkenes and readily available disulfides, thiols, or diselenides for the synthesis of diverse fluoroalkenyl 1,2-enedichalcogenides. Multiple carbon-halogen bonds in perfluoroalkyl-containing alkenyl iodides can be selectively cleaved under mild and transition-metal-free conditions. This protocol features a broad substrate scope, good scalability, and the ability to modify complex molecules. Mechanistic studies revealed that the key step in the reaction is the formation of a reactive fluoroallene, which is readily attacked by nucleophilic thiolate anions to achieve an unconventional defluorinative chalcogenation.
基金supported by the National Natural Science Foundation of China(No.51725401 and 51874019)the Fundamental Research Funds for the Central Universities(FRF-TP-17-002C2)。
文摘Aluminum batteries are attractive in electrochemical energy storage due to high energy density and lowcost aluminum,while the energy density is limited for the lack of favorable positive electrode materials to match aluminum negative electrodes.Tellurium positive electrode is intrinsically electrically conductive among chalcogen and holds high theoretical specific capacity(1260.27 mAh g^(-1)) and discharge voltage plateau(~1,5 V).However,the chemical and electrochemical dissolution of Te active materials results in the low material utilization and poor cycling stability.To enhance the electrochemical performance,herein a nitrogen doped porous carbon(N-PC) is derived from zeolite imidazolate framework(ZIF-67)as an effective tellurium host to suppress the undesired shuttle effect.In order to inhibit the volume expansion of N-PC during the charge/discharge process,the reduced graphene oxide(rGO) nanosheets are introduced to form a stable host materials(N-PC-rGO) for stabilizing Te.The physical encapsulation and chemical confinement to soluble tellurium species are achieved.N-PC-rGO-Te positive electrode exhibits an improved initial specific capacity and long-term cycling performance at a current density of 500 mA g^(-1)(initial specific capacity:935.5 mAh g^(-1);after 150 cycles:467.5 mAh g^(-1)), highlighting a promising design strategy for inhibiting chemical and electrochemical dissolution of Te.
基金supported by the National Science Fund for Distinguished Young Scholars(21425729)from the National Natural Science Foundation of Chinathe National Special S&T Project on Water Pollution Control and Treatment(2017ZX07107002)+1 种基金China Postdoctoral Science Foundation(2018M640209)the Tianjin Science and Technology Support Key Projects(18YFZCSF00500)~~
文摘The electroactive materials used in the counter electrode(CE)are of great concern as they influence the photovoltaic performances of dye-sensitized solar cells.The main functions of CE materials are collecting electrons from the external circuit and transferring them to the electrolyte and realizing the catalytic reduction of the redox species(I3^– or Co^3+)present in the electrolyte.The research hotspot of CE materials is seeking functional materials that display high efficiency,low cost,and good electrochemical stability and can substitute the benchmark platinum electrode.Chalcogen compounds of cobalt,nickel,and iron have been widely applied as CE materials and exhibit excellent electrocatalytic performances owing to their unique electrical properties,similar energies of adsorption of I atoms as platinum,excellent catalytic activities,and good chemical stabilities.In this review,we trace the developments and performances of chalcogen compounds of iron,cobalt,and nickel as CE materials and present the latest research directions for improving the electrocatalytic performances.We then highlight the optimization strategies for further improving their performances,such as fabrication of architectures,regulation of the components,synthesis of composites containing carbon materials,and elemental doping.
基金supported by the National Natural Science Foundation of China (No. 21801007)Qingchuang Technology Support Program of University in Shandong Province (No. 2021KJ066)Hunan Engineering Laboratory for analyse and Drugs Development of Ethnomedicine in Wunlin Mountains (No. Hgxy2103)。
文摘Chalcogenative sulfones(thiosulfonates and selenosulfonates), as reactants for organic transformations,are widely used and interesting because of their potential to react with nucleophiles, electrophiles, and free radicals. As stable radical reagents, the synthesis and applications of chalcogenative sulfones have opened up a novel pathway to synthesize many kinds of compounds containing sulfur or selenium motifs. However, despite the numerous recent works on the synthesis and applications of thiosulfonates and selenosulfonates as radical reagents, no review has yet provided a summary of the literature. In this paper, we aim to review the synthesis and applications strategies of chalcogenative sulfones as radical reagents reported over the past several decades. Different types of catalysis are discussed in this review:(i) metal catalysis;(ii) visible-light catalysis;(iii) synergistic catalysis;and(iiii) other types. Concurrently,in visible-light catalysis and metallaphotoredox catalysis sections, we highlight that developing relatively environmentally friendly synthetic methods in this area is always a great challenge, but also a persistent pursuit. Finally, the scopes, limitations, mechanisms, and existing problems of some reactions are described briefly.
文摘Using ethylene glycol as solvent and reductant, CuCl2-2H2O, （NH2）2CS and self-prepared GaCl3 as the starting materials, CuGaS2 nanostrucutures were synthesized on a large scale at 220℃. Powder X-ray diffraction. transmission electron microscopy, field-emission scanning electron microscope, high-resolution transmission electron microscopy＂ and X-ray＂ photoelectron spectroscopy were used to characterize the products. It demonstrated the evolution of the CuGaS2 particles from spherical assemblies to flowerlike morphology, over time, at 220℃. Simultaneously, we elucidated the specific roles of reaction temperature, reaction time and solvent in the formation of the final CuGaS2 nanostructures. A possible formation mechanism of CuGaS2 nanostrucutures was also discussed. The room temperature photoluminescence spectrum showed blue-shift and an increase of intensity, with a decrease in the sizes of CuGaS2 particles.
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.
文摘We have reported a first principles study of structural, mechanical, electronic, and thermoelectric properties of the monoclinic ternary thallium chalcogenes Tl2MQ3(M = Zr, Hf;Q = S, Se, Te). The electronic band structure calculations confirm that all compounds exhibit semiconductor character. Especially, Tl2ZrTe3 and Tl2HfTe3 can be good candidates for thermoelectric materials, having narrow band gaps of 0.169 eV and 0.21 eV, respectively. All of the compounds are soft and brittle according to the second-order elastic constant calculations. Low Debye temperatures also support the softness. We have obtained the transport properties of the compounds by using rigid band and constant relaxation time approximations in the context of Boltzmann transport theory. The results show that the compounds could be considered for room temperature thermoelectric applications(ZT ~ 0.9).
基金supported by the construct program of applied characteristic discipline in Hunan University of Science and Engineering,the Technology Plan of Guangdong Province(No. 2019A050510042)the Natural Science Foundation of Hunan Province of China (No. 2021JJ30291)Northwestern Polytechnical University。
文摘Artificial membrane transporters that either use chalcogen bonds to facilitate transmembrane flux of anions or show high selectivity toward perchlorate anions are rare.In this work,we report on one such novel monopeptide-based transporter system,featuring both chalcogen bonds for highly efficient anion transport and high transport selectivity toward ClO_(4)^(-) anions.Structurally,these monopeptide molecules associate with each other via H-bonds to produce H-bonded 1D stack that not only one dimensionally but also directionally aligns the terminal bicyclic thiophene motifs to the same side.Functionally,these well-aligned thiophenes create a sulfur-rich transmembrane pathway,combinatorially fine-tunable to enable anions to efficiently cross the membrane in the increasing activity of Cl^(-)<Br^(-)<NO_(3)^(-)<ClO_(4)^(-) via chalcogen bonds,with EC_(50)values of 0.75,0.40,0.37 and 0.093μmol/L(0.3 mol%relative to lipid molecules),respectively.
基金supported by the Special Scientific Research Fund for Talents Introduced of Hebei Agricultural University (No.YJ2019030)the National Natural Science Foundation of China (Nos.22276042,21906035)the Pearl River Young Talents Program of Guangdong Province (No.2017GC010269)。
文摘Increasing risks of incidental and occupational exposures to two-dimensional transition metal dichalcogenides(2D TMDCs)due to their broad application in various areas raised their public health concerns.While the composition-dependent cytotoxicity of 2D TMDCs has been well-recognized,how the outer chalcogenide atoms and inner transition metal atoms differentially contribute to their perturbation on cell homeostasis at non-lethal doses remains to be identified.In the present work,we compared the autophagy induction and related mechanisms in response to WS_(2),NbS_(2),WSe_(2)and Nb Se_(2)nanosheets exposures in MH-S murine alveolar macrophages.All these 2D TMDCs had comparable physicochemical properties,overall cytotoxicity and capability in triggering autophagy in MH-S cells,but showed outer chalcogen-dependent subcellular localization and activation of autophagy pathways.Specifically,WS_(2)and NbS_(2)nanosheets adhered on the cell surface and internalized in the lysosomes,and triggered m TOR-dependent activation of autophagy.Meanwhile,WSe_(2)and Nb Se_(2)nanosheets had extensive distribution in cytoplasm of MH-S cells and induced autophagy in an m TOR-independent manner.Furthermore,the 2D TMDCs-induced perturbation on autophagy aggravated the cytotoxicity of respirable benzo[a]pyrene.These findings provide a deeper insight into the potential health risk of environmental 2D TMDCs from the perspective of homeostasis perturbation.
基金supported by the National Natural Science Foundation of China (22002046 and 22379119)the Qin Chuangyuan High-level Innovative and Entrepreneurial Talent Program of Shaanxi Province (QCYRCXM-2023-045)+1 种基金the Youth Talent Support Program of Xi’an Association for Science and Technology (959202313070)the Young Top-notch Talent Program of Xi’an Jiaotong University (HG6J028)。
文摘The in-situ generated oxyanions at electrochemically reconstructed catalysts from metal-based nonoxide compounds have been proven to significantly accelerate oxygen evolution reaction(OER)kinetics.However,it remains a challenge to retain these self-released oxyanions at reconstructed catalysts,hindering its utilization as a tool to develop efficient OER catalysts.Here,we demonstrate a versatile selftransformed carbonate regulation strategy to efficiently retain the self-released chalcogenate at Co oxyhydroxides reconstructed from carbon-incorporated Co selenides under OER conditions.These selftransformed CO_(3)^(2-)can induce electron accumulation and narrow d bond at Co sites to facilitate the Co3d-O 2p orbital hybridization between Co sites and SeO_(x)^(2-)for enhanced SeO_(x)^(2-)retention,which can accelerate the rate-limiting step for^(*)OOH formation during OER.Relative to CoOOH-SeO_(x)^(2-)with limited SeO_(x)^(2-)residues,CoOOH-CO_(3)^(2-)/SeO_(x)^(2-)with elevated SeO_(x)^(2-)retention by CO_(3)^(2-)regulation exhibited a 5.6-fold increase in current density and a remarkable lower Tafel slope towards OER.This strategy paves a rational avenue to design efficient catalysts for electrooxidation reactions through finely regulating self-released oxyanions at reconstructed structures.
基金supported by Distinguished Young Scholar Fund Project of Hunan Province Natural Science Foundation(No.2023JJ10041)the Hunan Provincial Education Office Foundation of China(No.21B0147)+3 种基金the Science and Technology Program of Xiangtan(No.GX-ZD20211004)the Hunan Provincial united foundation(No.2022JJ50136)the National Natural Science Foundation of China(No.52003230)the Science and Technology Innovation Program of Hunan Province(No.2021RC2091)。
文摘Strategic active site organization is imperative for the advancement of effective and long-lasting catalysts of oxygen reduction reactions.However,the controllable multi-active site design is a highly intricate topic for catalyst synthesis.Employing pre-trapping and post-activation strategy,Fe-N bonding structure and S,Se functionalized heteroatom are integrated into a conductive porous carbon.In this process,the nitrogen-abundant polymer 1,3,5-triformylbenzene-tris(4-aminophenyl)benzene(Tf-TAPA)adsorbs Fe^(3+)under the intrinsically metal anchoring ability of N atoms and simultaneously in-situ assembles longchain thiophene-S.Subsequently,the Fe^(3+)is transformed into Fe-N_(x)moieties with the conversion of the organic chain to incompletely graphitized carbon.Furthermore,the alteration of the electronic configuration achieved through the introduction of dual-atom S and Se leads to a pronounced enhancement in catalytic efficiency.Benefitting from the Fe-N_(x)bonding structure,dense structural defects,and conductive carbon networks,the resultant Fe-S,Se/NCNs possesses a positive half-wave potential of 0.86 V and a 90%current retention rate,outstripping the Pt/C benchmark.Moreover,the liquid and flexible ZAB driven by Fe-S,Se/NCNs achieves large power densities of 259.7 and 164.7 m W/cm^(2),respectively.This study provides a new comprehension in developing an efficient and stable M-N-C oxygen electrocatalyst.
基金supported by funds from scientific research programs of National Academy of Sciences of Ukraine and Ministry of Education and Science of Ukraine
文摘The gas phase methane oxidative carbonylation was studied in the presence of molecular oxygen over silica materials including their mechanical mixtures with rhodium chalcogen chlorides obtained in non-aqueous inorganic media. The formation of Rh4SCl7, Rh4S9Cl2, Rh4SesCl3 and Rh3Se3Cl solids was confirmed by elemental analysis, IR absorption spectroscopy, XPS and X-ray diffraction. Silica, vanadium-, and molybdenum-containing mesoporous molecular sieves have been used as supports. It was found that productivity of oxygenates （methanol, methyl acetate and acetic acid） depends mainly on the method of the catalyst preparation and the type of the support.
文摘The electronic configuration of central metal atoms in single-atom catalysts(SACs)is pivotal in electrochemical CO_(2) reduction reaction(eCO_(2)RR).Herein,chalcogen heteroatoms(e.g.,S,Se,and Te)were incorporated into the symmetric nickel-nitrogen-carbon(Ni-N_(4)-C)configuration to obtain Ni-X-N_(3)-C(X:S,Se,and Te)SACs with asymmetric coordination presented for central Ni atoms.Among these obtained Ni-X-N_(3)-C(X:S,Se,and Te)SACs,Ni-Se-N_(3)-C exhibited superior eCO_(2)RR activity,with CO selectivity reaching~98% at-0.70 V versus reversible hydrogen electrode(RHE).The Zn-CO_(2) battery integrated with Ni-Se-N_(3)-C as cathode and Zn foil as anode achieved a peak power density of 1.82 mW cm^(-2) and maintained remarkable rechargeable stability over 20 h.In-situ spectral investigations and theoretical calculations demonstrated that the chalcogen heteroatoms doped into the Ni-N_(4)-C configuration would break coordination symmetry and trigger charge redistribution,and then regulate the intermediate behaviors and thermodynamic reaction pathways for eCO_(2)RR.Especially,for Ni-Se-N_(3)-C,the introduced Se atoms could significantly raise the d-band center of central Ni atoms and thus remarkably lower the energy barrier for the rate-determining step of ^(*)COOH formation,contributing to the promising eCO_(2)RR performance for high selectivity CO production by competing with hydrogen evolution reaction.
文摘This paper presents a versatile method for synthesizing electron-rich polynuclear transition metal clusters with chalcogen bridges and phosphine ligands.The reactions of transition metal complexes(R3P)2MX2(M=Co,Ni;R=Ph,Bu,Et;X=Cl,Br) with bridging reagents Na2Ex (E=S,Se;x=1.2) are described.The geometric and electronic structures of a series of polynuclear transition metal clusters with trianglar M3 units are also discussed.
文摘Growing interest in non-covalent interactions involving chalcogen atoms has been ascribed to their importance in crystal engineering, molecular recognition and macromolecular edifices. The present study is dealing with chalcogen bonds involving divalent Sulphur, Selenium and Tellurium atoms, acting as sigma-hole donors, in small-molecule compounds using the Cambridge Structural Database (CSD) in conjunction with ab initio calculations. Results derived from CSD surveys and computational study revealed that nucleophiles formed complexes with the chalcogen-bond donors R1-X-R2 (X = S, Se or Te). The main forces stabilizing the complexes were chalcogen bonds, enhanced by dispersion interactions. Complexation pattern and energetics show that nucleophile bonding at divalent S, Se and Te atoms is a relatively strong and directed interaction. The bond consists of a charge transfer from a nucleophile atom lone pair to an X-R1 or X-R2 antibonding orbital.
基金the Natural Science Foundation of China(grant nos.22205172,22175138,22201228,and 52203240)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(grant nos.20220604 and 20230624)+4 种基金the China National Postdoctoral Program for Innovative Talents(grant no.BX2021231)the China Postdoctoral Science Foundation(grant nos.2022M712497 and 2022M712530)Shaanxi Province Technological Innovation Guidance Special(grant nos.2024ZC-YYDY-96 and 2022QFY08-01)the Fundamental Research Funds for the Central Universities,China(grant nos.xhj032021008-03,sxjh032021099,and xzy012022017)the Taihu Lake lnnovation Fund for the School of Future Technology of Xi’an Jiaotong University,China.
文摘Photocatalytic CO_(2)reduction and conversion into fuel or high-value-added chemicals are expected to solve environmental and energy problems such as fossil fuel depletion and global warming.Efficient electron transport between the photosensitizer and the catalyst is crucial for improving the photocatalytic effect.Herein,mononuclear rhenium(I)tethered selenoviologen(HOOC-SeV-Re)was covalently linked to the surface of amine-polyethylene glycol(PEG)-protected black phosphorus quantum dots(BPQDs@PEG)via amide bonds,forming the heterojunction BPQDs@PEG-SeV-Re.The heterojunction features a high specific surface area,broad-spectrum absorption,and efficient staggered gap catalysis.The integration of selenoviologen not only enhances visible light excitation but also suppresses electron-hole recombination,thereby fostering the formation of radical states and facilitating two consecutive intramolecular electron transfer processes.This selfphotosensitized system produces CO with a rapid generation rate(41.48 mmol·h^(−1)·g^(−1)),high turnover number(428.0),and CO selectivity(exceeded 99%).Additionally,Pd-catalytic carbonylation reactions were combined with photocatalytic CO_(2)reduction to produce molecular drugs and functional polymers using a two-chamber reactor,which supplied a new strategy for the conversion and utilization of CO_(2).
基金supported by the National Natural Science Foundation of China(U23A20593,12234001,22071003,62104013,and 92156016)the National Key R&D Program of China(2021YFB3501800,2021YFB3500400,2022YFB3503700,2022YFF0710001,and 2023YFB3506901).
文摘Luminescent lanthanide cerium(III) compounds have gathered increasing research interest in both inorganic phosphors and functional molecular complexes. Cerium(III) exhibits broad double-peak emission originating from 5d excited state 2D3/2 to 4f ground states 2F7/2 and 2F5/2. It is vital to adjust the bandwidth of the emission for different applications like lighting and display, while no regulation between these two peaks in Ce(III) emitters has been reported hitherto. In this work, novel heavy-atom-induced narrow emission is observed in luminescent Ce(III) complexes by adopting imidodiphosphinate ligand with different chalcogen-coordinating sites from O to S, Se, and Te. Not only a new Ce(III) complex with orange–red emission beyond the traditional emission color regions of Ce(III) was obtained, but also the ratio of the two peaks was systematically tuned to achieve the narrowest emission from Ce(III) with a full width at half maximum of 42 nm. Time-dependent density functional theory calculations ascribe the tuning of emission spectra to centroid shift and simultaneously provide the orbital contribution values of different chalcogen atoms to the emission excited state. By extending the coordination atoms from classic oxygen and nitrogen to heavier and softer elements, these results give new insight into luminescence properties and mechanisms of Ce(III) emission.
基金financially supported by the National Natural Science Foundation of China(grant nos.92156010,22071247,22101283,and 22101284)the Strategic Priority Research Program(grant no.XDB20000000)+1 种基金the Key Research Program of Frontier Sciences(grant no.QYZDB-SSW-SLH030)of Chinese Academy of Sciences,Natural Science Foundation of Fujian Province(grant nos.2020J06035 and 2022J05085)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(grant no.2021ZR112)for support.
文摘Molecular photoswitches hold an important position in chemical research,and it is of significance to develop novel structures and mechanisms.Herein we report a new type of E/Z photoswitches in tellurazole/tellurazolium-based olefin scaffolds,wherein intramolecular through-space n→π^(*)orbital interaction plays a stabilizing role in the Z isomer approaching quantitative conversion.The manipulation of diverse noncovalent interactions,including intermolecular chalcogen bonding,further provided versatile handles for regulating molecular recognition and multiaddressable switching.Despite bidirectional E/Z photoisomerization with neutral tellurazole derivatives,protonation-induced cationic tellurazoliums allowed significant enhancement in the efficiency of Z→E switching(E up to 73%)while maintaining high percentage E→Z switching(Z up to 95%),as chalcogen bonding with counteranions contributes to the stabilization of electron-accepting tellurazoliums affording a larger wavelength difference between E/Z isomers.Furthermore,the n→π^(*)orbital interaction enables the preference of Z isomer in the ground state for N-methyl tellurazoliums.Bidirectional E/Z photoswitching with high conversion(Z up to 99%,E up to 81%)was attained,and E→Z isomerization can also be invoked by nucleophilic catalysis,making N-methyl tellurazoliums as T-type photoswitches.The results showcase the power of noncovalent interactions for controlling molecular photoswitches and should set the scene for vip recognition,dynamic assemblies,and responsive materials.
基金financial support from the National Natural Science Foundation of China(Nos.22173103,52063008)the Academic Talent Plan of Guizhou Normal University(No.Qian Shi Xin Miao[2021]27)the Fundamental Research Funds for the Central Universities and Beijing National Laboratory for Molecular Sciences(BNLMS2023014).
文摘Cross-coupling reactions between aryl halides and thiolates or selenolates typically require transition metals,photocatalysts,strong bases,or/and malodorous thiols/selenols,with various mechanisms proposed.This study aims to leverage a new application of neutral ChB to address these challenges and enable a very simple photoinduced cross-electrophile C—S/Se coupling using readily available chalcogen electrophiles.Mechanistic investigations have revealed the important role of neutral ChB in facilitating single electron transfer processes,thereby enabling the generation of thiolates/selenolates from stable chalcogen electrophiles andα-aminoalkyl radicals,which possess the capability to abstract halogen atoms from aryl iodides.Moreover,the study provided support for the radical nucleophilic substitution mechanism.
