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
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
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
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
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
The solid-state structures of co-crystals of chalcogenadiazoles(ChDAs)with planar half-lantern Pt_(2)^(Ⅱ) and mononuclear Pt^(Ⅱ)complexes exhibit short Ch…Pt^(Ⅱ)(Ch=Se,Te)contacts that occur between a metal site a...The solid-state structures of co-crystals of chalcogenadiazoles(ChDAs)with planar half-lantern Pt_(2)^(Ⅱ) and mononuclear Pt^(Ⅱ)complexes exhibit short Ch…Pt^(Ⅱ)(Ch=Se,Te)contacts that occur between a metal site and the ChDA.The structures demonstrate a unique geometric feature whereby the two deepσ-holes of ChDA are turned away from a d_(z^(2))-nucleophilic PtII site.展开更多
A series of tetrahedral Co(II)complexes with chalcogen donors were prepared,which exhibited strong magnetic uniaxial anisotropies and slow relaxations as SIMs.By substituting donors from S to Te,we realized the fine-t...A series of tetrahedral Co(II)complexes with chalcogen donors were prepared,which exhibited strong magnetic uniaxial anisotropies and slow relaxations as SIMs.By substituting donors from S to Te,we realized the fine-tuning of the ligand field while keeping the coordination geometry virtually unchanged,yielding the first tellurium-coordinated SIM.展开更多
A series of p-alkylthio-substituted phenyl-1,2,3,5-dithiadiazolyl radicals,p-R-PhDTDA(R=SMe(2),SEt(3),S^(n)Pr(4),S^(i)Pr(5),S^(t)Bu(6)),and the prototypical(R=H(1))phenyl derivative exhibit a thermally driven solid-li...A series of p-alkylthio-substituted phenyl-1,2,3,5-dithiadiazolyl radicals,p-R-PhDTDA(R=SMe(2),SEt(3),S^(n)Pr(4),S^(i)Pr(5),S^(t)Bu(6)),and the prototypical(R=H(1))phenyl derivative exhibit a thermally driven solid-liquid transition accompanied by a spin-state change from diamagnetic(S=0)π-dimers to a pair of paramagnetic(S=1/2)radicals.X-ray crystallography reveals that most derivatives form phase-pure ciscofacial dimers,except 3 which crystallizes as three distinct polymorphs:3αdisplays a sandwich-type herringbone structure stabilized by intermolecular S…S chalcogen bonding(isostructural with 2)while 3βand 3γfeature slippedπ-stacked herringbone arrangements(ABAB and AA’BB’,respectively).In these latter forms,the alkyl groups act as steric buffers between adjacent stacks,a structural motif retained in derivatives 4-6.Differential scanning calorimetry(DSC),hot-stage microscopy,and vibrating sample magnetometry(VSM)collectively demonstrate a hysteretic phase transition in 1-6 with magnetic bistability arising from supercooling of the paramagnetic liquid phase.These results establish a new design paradigm for stimuli-responsive materials in which molecular packing,thermal behavior,and spin states are intrinsically linked through phase transitions.展开更多
The interactions of tripleσ-(Q^(IV))-hole donating chalconium cations([Q(bPh)R]^(+),when Q=S,Se,and Te)with nucleophilic beta-octamolybdate([β-Mo_(8)O_(26)]^(4-))result in supramolecular association.The main focus o...The interactions of tripleσ-(Q^(IV))-hole donating chalconium cations([Q(bPh)R]^(+),when Q=S,Se,and Te)with nucleophilic beta-octamolybdate([β-Mo_(8)O_(26)]^(4-))result in supramolecular association.The main focus of such assembly is onσ-(Q^(IV))-hole recognition by the molybdate in cations with a biphenyl aromatic fragment.This leads to a remarkable diversity of the association patterns producing:(i)neutral 4:1{[Q(bPh)R]^(4)[β-Mo_(8)O_(26)]}complexes with cations stacked byπ-πinteractions;(ii)(Bu_(4)N)^(+),[Q(bPh)R]^(+)and[β-Mo_(8)O_(26)]^(4-)complexes of 2:2:1 stoichiometry withπ-πinteractions;(iii)(Bu4N)+,[Q(bPh)R]+and[β-Mo_(8)O_(26)]^(4-)complexes of a 2:2:1 stoichiometry withoutπ-πinteractions;and(iv){[Q(bPh)R]_(2)}_(2)[β-Mo_(8)O_(26)]salts withπ-πstacked cations but lacking any(Q^(IV))…O interactions.Moreover,interactions in the system can drive the reorganization of[β-Mo_(8)O_(26)]4-into[α-Mo_(8)O_(26)]^(4-).The halogen-bonded(Q^(IV))…O{(Q(bPh)R)_(x)[β-Mo_(8)O_(26)]^(4-)}(x=2 and 4)assemblies,π-πstacked cationic dimers{(Q(bPh)R)_(2)}^(2+)and complicated associates based on both types of interactions have been the subjects of crystallographic and computational studies.展开更多
The dichalcogenides Ph_(2)Ch_(2)(Ch=S,Se,Te)were cocrystallized with perfluorinated chalcogen bond donors Tol_(2)^(F)Te and Py_(2)^(F)Te(Tol^(F)=4-CF_(3)C_(6)F_(4),PyF=4-NC_(5)F_(4))to obtain the 1:1 cocrystals Tol_(2...The dichalcogenides Ph_(2)Ch_(2)(Ch=S,Se,Te)were cocrystallized with perfluorinated chalcogen bond donors Tol_(2)^(F)Te and Py_(2)^(F)Te(Tol^(F)=4-CF_(3)C_(6)F_(4),PyF=4-NC_(5)F_(4))to obtain the 1:1 cocrystals Tol_(2)^(F)Te·Ph_(2)Ch_(2)(Ch=S 1,Se 2,Te 3)and Py_(2)^(F)Te·Ph_(2)Se_(2)(4).In the X-ray structures of 1-4,heterovalent Te^(Ⅱ)…Ch^(Ⅰ)(Ch=S,Se,Te)chalcogen bonding was identified on consideration of the geometrical parameters and,in addition,based on the results of appropriate density functional theory(DFT)calculations including quantum theory of atoms-in-molecules(QTAIM),noncovalent interaction plot(NCIplot)analysis,molecular electrostatic potential surfaces(MEP),and atoms-in-molecules(AIM)charge analysis.The binding energy in the dimeric structure is in the range between -9.7 and -12.9 kcal mol^(-1),where the contribution of the heterovalent chalcogen bonding ranges from -4.7 to -6.5 kcal mol^(-1).In the Te^(Ⅱ)…Ch^(Ⅰ) moiety,the Te^(Ⅱ) center plays the role of an electrophilic partner,while the chalcogens in the lower oxidation state,1+,exhibit nucleophilic properties.The heterovalent Te^(Ⅱ)…Ch^(Ⅰ)(Ch=Se,Te)chalcogen bonding was thus used for the targeted noncovalent integration of two Ch centers in different oxidation states.展开更多
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 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 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.
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 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support of the Russian Science Foundation(project 21-73-00056)is gratefully acknowledged.Physicochemical studies were performed at the Center for Magnetic Resonance,Center for X-ray Diffraction Studies and Center for Chemical Analysis and Materials Research,while theoretical calculations were performed at the Computational Center(all belonging to Saint Petersburg State University)M.L.K.thanks the Fundação para a Ciência e a Tecnologia(FCT),Portugal,projects UIDB/00100/2020 and UIDP/00100/2020 of Centro de Química Estrutural and LA/P/0056/2020 of the Institute of Molecular Sciences for putting facilities at his disposal.The authors express their gratitude to Dr A.V.Rozhkov for his kind assistance with glove-box manipulations.
文摘The solid-state structures of co-crystals of chalcogenadiazoles(ChDAs)with planar half-lantern Pt_(2)^(Ⅱ) and mononuclear Pt^(Ⅱ)complexes exhibit short Ch…Pt^(Ⅱ)(Ch=Se,Te)contacts that occur between a metal site and the ChDA.The structures demonstrate a unique geometric feature whereby the two deepσ-holes of ChDA are turned away from a d_(z^(2))-nucleophilic PtII site.
基金funded by the National Natural Science Foundation of China(21222208,21321001,91422302,21421091 and 21432001)the National Key Basic Research Program of China(2013CB933401 and 2011CB808705).We also thank Prof.Wei Tong for his help in the EPR measurement.
文摘A series of tetrahedral Co(II)complexes with chalcogen donors were prepared,which exhibited strong magnetic uniaxial anisotropies and slow relaxations as SIMs.By substituting donors from S to Te,we realized the fine-tuning of the ligand field while keeping the coordination geometry virtually unchanged,yielding the first tellurium-coordinated SIM.
基金supported by the Academy of Finland(projects 358156,336456,333565)the University of Jyväskylä,and the authors are grateful for technical and human support provided by SGIker(UPV/EHU/ERDF,EU),especially the fruitful discussions with Dr I.Orue.
文摘A series of p-alkylthio-substituted phenyl-1,2,3,5-dithiadiazolyl radicals,p-R-PhDTDA(R=SMe(2),SEt(3),S^(n)Pr(4),S^(i)Pr(5),S^(t)Bu(6)),and the prototypical(R=H(1))phenyl derivative exhibit a thermally driven solid-liquid transition accompanied by a spin-state change from diamagnetic(S=0)π-dimers to a pair of paramagnetic(S=1/2)radicals.X-ray crystallography reveals that most derivatives form phase-pure ciscofacial dimers,except 3 which crystallizes as three distinct polymorphs:3αdisplays a sandwich-type herringbone structure stabilized by intermolecular S…S chalcogen bonding(isostructural with 2)while 3βand 3γfeature slippedπ-stacked herringbone arrangements(ABAB and AA’BB’,respectively).In these latter forms,the alkyl groups act as steric buffers between adjacent stacks,a structural motif retained in derivatives 4-6.Differential scanning calorimetry(DSC),hot-stage microscopy,and vibrating sample magnetometry(VSM)collectively demonstrate a hysteretic phase transition in 1-6 with magnetic bistability arising from supercooling of the paramagnetic liquid phase.These results establish a new design paradigm for stimuli-responsive materials in which molecular packing,thermal behavior,and spin states are intrinsically linked through phase transitions.
基金support(grant number 103922061)Physicochemical studies were performed at the Center for Magnetic Resonance,Center for X-ray Diffraction Studies,and Center for Chemical Analysis and Materials Research(all at Saint Petersburg State University)the RUDN University Scientific Projects Grant System(project no.021342-2-000).
文摘The interactions of tripleσ-(Q^(IV))-hole donating chalconium cations([Q(bPh)R]^(+),when Q=S,Se,and Te)with nucleophilic beta-octamolybdate([β-Mo_(8)O_(26)]^(4-))result in supramolecular association.The main focus of such assembly is onσ-(Q^(IV))-hole recognition by the molybdate in cations with a biphenyl aromatic fragment.This leads to a remarkable diversity of the association patterns producing:(i)neutral 4:1{[Q(bPh)R]^(4)[β-Mo_(8)O_(26)]}complexes with cations stacked byπ-πinteractions;(ii)(Bu_(4)N)^(+),[Q(bPh)R]^(+)and[β-Mo_(8)O_(26)]^(4-)complexes of 2:2:1 stoichiometry withπ-πinteractions;(iii)(Bu4N)+,[Q(bPh)R]+and[β-Mo_(8)O_(26)]^(4-)complexes of a 2:2:1 stoichiometry withoutπ-πinteractions;and(iv){[Q(bPh)R]_(2)}_(2)[β-Mo_(8)O_(26)]salts withπ-πstacked cations but lacking any(Q^(IV))…O interactions.Moreover,interactions in the system can drive the reorganization of[β-Mo_(8)O_(26)]4-into[α-Mo_(8)O_(26)]^(4-).The halogen-bonded(Q^(IV))…O{(Q(bPh)R)_(x)[β-Mo_(8)O_(26)]^(4-)}(x=2 and 4)assemblies,π-πstacked cationic dimers{(Q(bPh)R)_(2)}^(2+)and complicated associates based on both types of interactions have been the subjects of crystallographic and computational studies.
基金supported by the Russian Science Foundation(project 21-73-10030:synthetic experiments,project 19-13-00338:crystal engineering studies)funded by MICIU/AEI of Spain(project PID2020-115637GB-I00 FEDER funds).
文摘The dichalcogenides Ph_(2)Ch_(2)(Ch=S,Se,Te)were cocrystallized with perfluorinated chalcogen bond donors Tol_(2)^(F)Te and Py_(2)^(F)Te(Tol^(F)=4-CF_(3)C_(6)F_(4),PyF=4-NC_(5)F_(4))to obtain the 1:1 cocrystals Tol_(2)^(F)Te·Ph_(2)Ch_(2)(Ch=S 1,Se 2,Te 3)and Py_(2)^(F)Te·Ph_(2)Se_(2)(4).In the X-ray structures of 1-4,heterovalent Te^(Ⅱ)…Ch^(Ⅰ)(Ch=S,Se,Te)chalcogen bonding was identified on consideration of the geometrical parameters and,in addition,based on the results of appropriate density functional theory(DFT)calculations including quantum theory of atoms-in-molecules(QTAIM),noncovalent interaction plot(NCIplot)analysis,molecular electrostatic potential surfaces(MEP),and atoms-in-molecules(AIM)charge analysis.The binding energy in the dimeric structure is in the range between -9.7 and -12.9 kcal mol^(-1),where the contribution of the heterovalent chalcogen bonding ranges from -4.7 to -6.5 kcal mol^(-1).In the Te^(Ⅱ)…Ch^(Ⅰ) moiety,the Te^(Ⅱ) center plays the role of an electrophilic partner,while the chalcogens in the lower oxidation state,1+,exhibit nucleophilic properties.The heterovalent Te^(Ⅱ)…Ch^(Ⅰ)(Ch=Se,Te)chalcogen bonding was thus used for the targeted noncovalent integration of two Ch centers in different oxidation states.
