Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes...Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes, i.e., global instability index（GII） and bond strain index（BSI）, are adopted as a judgment of a search-match program for prediction. The results show that with GII and BSI combined as judgment, the predicted atom positions are very close to real ones. The mechanism and validity of this searching program are also discussed. The GII ＆ BSI distribution contour map reveals that the predicted function is a reflection of exponential feature of bond valence formula. This combined searching method may be integrated with other structure-determination method, and may be helpful in refining and testifying light atom positions.展开更多
Different ternary system Fe-based metallic glass catalysts were constructed to boost photocatalytic reac-tive black 5 dye degradation with persulfate assistance.Compared with FePC and FeBSi catalysts,Fe atoms in the F...Different ternary system Fe-based metallic glass catalysts were constructed to boost photocatalytic reac-tive black 5 dye degradation with persulfate assistance.Compared with FePC and FeBSi catalysts,Fe atoms in the FeBC catalyst exhibited a high energy level and a unique atomic coordination structure causing its efficient photocatalytic activity like a high k value,a strong total organic carbon removal rate,and a low activation energy value.Meanwhile,the green and environmental friendliness of the metallic glass cata-lyst/persulfate/ultraviolet system for dye degradation was determined.Density Functional Theory simula-tions confirmed that the FeBC catalyst had an excellent catalytic performance due to its unique atomic coordination environment,which induced the reduction in the energy barrier(only 1.36 eV)during the conversion of S2 O82−to SO_(4)−•.Moreover,the Relaxation and Rejuvenation catalysts were prepared by treating the as spun FeBC ribbon with high temperature annealing and cryogenic thermal cycling,show-ing a higher crystallinity and a higher energy state than the as spun counterpart,respectively;and both treated catalysts exhibited a higher catalytic degradation activity.Especially,the Rejuvenation catalyst of-fered a high catalytic degradation ability of kSA·C0=13114 mg m^(−2) min^(−1),a large k value of 0.981 min^(−1),and a strong reusability of 44 cycles without decolorization efficiency decay.This study may inspire the design of high activity metallic glass catalysts and expand their potential applications in environmental remediation.展开更多
Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating ...Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization.展开更多
Atomically precise coordination nanoclusters(NCs)constitute a pivotal and rapidly advancing domain in the realms of materials science and chemistry owing to their distinctive crystal structures and exceptional attribu...Atomically precise coordination nanoclusters(NCs)constitute a pivotal and rapidly advancing domain in the realms of materials science and chemistry owing to their distinctive crystal structures and exceptional attributes encompassing molecular magnetism[1],photoluminescence[2],and catalysis[3].Organic ligands play a crucial role in effectively shielding these NCs,serving two primary functions:firstly,vital in preventing NC aggregation,particularly for the formation of robust single-crystal structures;secondly,acting as either bridging or peripheral structural components of NCs[4].This characterization of organic-inorganic hybridization offers unique advantages for unraveling the intricate relationships between structure and properties[5].展开更多
Aromatic bond including metallic atom (Ni) is investigated by EHMO calculation.The NMR spectra and the mechanism for hydrolysis are discussed on the ground of results of computation.
Tetra-coordinate boron-based fluorescent materials hold considerable promise across chemistry,biology and materials science due to their unique and precisely tunable optoelectronic properties.The incorporation of the ...Tetra-coordinate boron-based fluorescent materials hold considerable promise across chemistry,biology and materials science due to their unique and precisely tunable optoelectronic properties.The incorporation of the heteroatom boron(B)enables these materials to exhibit high luminescence quantum yields,adjustable absorption and emission wavelengths,and exceptional photostability.This review examines the molecular design and applications of tetra-coordinate boron-based photoactive molecules,highlighting their roles in fluorescence sensing,anticounterfeiting,and imaging.We outline how structural features impact their properties and discuss strategies for enhancing their performance,including ligand modification and the extension of conjugation length,among others.Additionally,future research focus in this field is also addressed including strategies for diversifying molecular structures and enhancing molecular stability,which is believed to pave the way for innovative solutions to the challenges in areas such as sensing,imaging and information security.展开更多
Single-atom catalysts(SACs)have emerged as a promising frontier in heterogeneous catalysis due to their high atomutilization efficiency and distinctive catalytic properties[1,2].Despite these advantages,conventional S...Single-atom catalysts(SACs)have emerged as a promising frontier in heterogeneous catalysis due to their high atomutilization efficiency and distinctive catalytic properties[1,2].Despite these advantages,conventional SACs frequently encounter limitations,such as the random dispersion of active sites and restricted electronic modulation arising from interactions with electronegative coordinating ligand atoms of supports[3].展开更多
Achieving high catalytic performance with lower possible cost and higher energetic efficiency is critical for catalytic oxidation of volatile organic compounds(VOCs).However,traditional thermocatalysts generally under...Achieving high catalytic performance with lower possible cost and higher energetic efficiency is critical for catalytic oxidation of volatile organic compounds(VOCs).However,traditional thermocatalysts generally undergo low catalytic activity and fewer active sites.Herein,this paper synthesizes nearly all-surface-atomic,ultrathin two-dimensional(2D)Co_(3)O_(4) nanosheets to address these problems through offering a numerous active sites and high electron mobility.The 2D Co_(3)O_(4) nanosheets(1.70 nm)exhibit catalyzation to the total oxidation of n-hexanal at the lower temperature of r90%=202℃,and at the space velocity of 5.0×10^(4) h^(-1).It is over 1.2 and 6 times higher catalytic activity than that of 2D CoO nanosheets(1.71 nm)and bulk Co_(3)O_(4) counterpart,respectively.Transient absorption spectroscopy analysis shows that the oxygen vacancy defect traps electrons,thereby preventing the recombination with holes,increasing the lifetime of electrons,and making electron-holes reach a nondynamic equilibrium.The longer the electron lifetime is,the easier the oxygen vacancy defects capture electrons.Furthermore,the defects combine with oxygen to form active oxygen components.Compared with the lattice oxygen involved in the reaction of bulk Co_(3)O_(4),the nanosheets change the catalytic reaction path,which effectively reduces the activation energy barrier from 34.07 to 27.15 kJ/mol.The changed surface disorder,the numerous coordinatively-unsaturated Co atoms and the high ratio of O_(ads)/O_(lat) on the surface of 2D Co_(3)O_(4) nanosheets are responsible for the catalytic performance.展开更多
基金Project supported by the National Natural Science Foundation of China(Grant No.51272027)
文摘Bond valence method illustrates the relation between valence and length of a particular bond type. This theory has been used to predict structure information, but the effect is very limited. In this paper, two indexes, i.e., global instability index（GII） and bond strain index（BSI）, are adopted as a judgment of a search-match program for prediction. The results show that with GII and BSI combined as judgment, the predicted atom positions are very close to real ones. The mechanism and validity of this searching program are also discussed. The GII ＆ BSI distribution contour map reveals that the predicted function is a reflection of exponential feature of bond valence formula. This combined searching method may be integrated with other structure-determination method, and may be helpful in refining and testifying light atom positions.
基金supported by the Key Research and Development Program of China(No.2022YFB2404102)the National Natural Science Foundation of China(Nos.51971093,52171158 and 52101196)+1 种基金the Open Project Program of Shan-dong Marine Aerospace Equipment Technological Innovation Cen-ter(Ludong University)(No.MAETIC2021-11)the Key Research and Development Program of Shandong Province(Nos.2021ZLGX01,2022CXGC020308 and 2023CXGC010308).
文摘Different ternary system Fe-based metallic glass catalysts were constructed to boost photocatalytic reac-tive black 5 dye degradation with persulfate assistance.Compared with FePC and FeBSi catalysts,Fe atoms in the FeBC catalyst exhibited a high energy level and a unique atomic coordination structure causing its efficient photocatalytic activity like a high k value,a strong total organic carbon removal rate,and a low activation energy value.Meanwhile,the green and environmental friendliness of the metallic glass cata-lyst/persulfate/ultraviolet system for dye degradation was determined.Density Functional Theory simula-tions confirmed that the FeBC catalyst had an excellent catalytic performance due to its unique atomic coordination environment,which induced the reduction in the energy barrier(only 1.36 eV)during the conversion of S2 O82−to SO_(4)−•.Moreover,the Relaxation and Rejuvenation catalysts were prepared by treating the as spun FeBC ribbon with high temperature annealing and cryogenic thermal cycling,show-ing a higher crystallinity and a higher energy state than the as spun counterpart,respectively;and both treated catalysts exhibited a higher catalytic degradation activity.Especially,the Rejuvenation catalyst of-fered a high catalytic degradation ability of kSA·C0=13114 mg m^(−2) min^(−1),a large k value of 0.981 min^(−1),and a strong reusability of 44 cycles without decolorization efficiency decay.This study may inspire the design of high activity metallic glass catalysts and expand their potential applications in environmental remediation.
基金National Natural Science Foundation of China(22309032,22109120,and 62104170)Guangdong Basic and Applied Basic Research Foundation(2022A1515011737)+2 种基金Science and Technology Program of Guangzhou(2023A04J1395)GDAS’Project of Science and Technology Development(2021GDASYL-20210102010)Zhejiang Provincial Natural Science Foundation of China(LY23F040001)。
文摘Photocatalytic oxygen reduction for hydrogen peroxide(H_(2)O_(2))synthesis presents a green and costeffective production method.However,achieving highly selective H_(2)O_(2)synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative by-products.Herein,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H_(2)O_(2)and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride(CNRb).The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h^(-1)for H_(2)O_(2)generation and photooxidation rate of 3.75 mM h^(-1)for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion(SCC)efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical formation.This is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product formation.This study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H_(2)O_(2)coupled with biomass valorization.
基金financial support from the National Natural Science Foundation of China(Nos.22171094,21925104,92261204,and 22431005)Hubei Provincial Science and Technology Innovation Team Project[2022]The National Key R&D Program of China(No.2022YFB3807700)。
文摘Atomically precise coordination nanoclusters(NCs)constitute a pivotal and rapidly advancing domain in the realms of materials science and chemistry owing to their distinctive crystal structures and exceptional attributes encompassing molecular magnetism[1],photoluminescence[2],and catalysis[3].Organic ligands play a crucial role in effectively shielding these NCs,serving two primary functions:firstly,vital in preventing NC aggregation,particularly for the formation of robust single-crystal structures;secondly,acting as either bridging or peripheral structural components of NCs[4].This characterization of organic-inorganic hybridization offers unique advantages for unraveling the intricate relationships between structure and properties[5].
文摘Aromatic bond including metallic atom (Ni) is investigated by EHMO calculation.The NMR spectra and the mechanism for hydrolysis are discussed on the ground of results of computation.
基金support from the National Natural Science Foundation of China(22427802,22132002)the National Key Research and Development Program of China(2022YFA1205502)the 111 project(B14041)for this work.
文摘Tetra-coordinate boron-based fluorescent materials hold considerable promise across chemistry,biology and materials science due to their unique and precisely tunable optoelectronic properties.The incorporation of the heteroatom boron(B)enables these materials to exhibit high luminescence quantum yields,adjustable absorption and emission wavelengths,and exceptional photostability.This review examines the molecular design and applications of tetra-coordinate boron-based photoactive molecules,highlighting their roles in fluorescence sensing,anticounterfeiting,and imaging.We outline how structural features impact their properties and discuss strategies for enhancing their performance,including ligand modification and the extension of conjugation length,among others.Additionally,future research focus in this field is also addressed including strategies for diversifying molecular structures and enhancing molecular stability,which is believed to pave the way for innovative solutions to the challenges in areas such as sensing,imaging and information security.
文摘Single-atom catalysts(SACs)have emerged as a promising frontier in heterogeneous catalysis due to their high atomutilization efficiency and distinctive catalytic properties[1,2].Despite these advantages,conventional SACs frequently encounter limitations,such as the random dispersion of active sites and restricted electronic modulation arising from interactions with electronegative coordinating ligand atoms of supports[3].
基金supported by National Natural Science Foundation of China(Nos.51808037,21601136,and 21876010)Fundamental Research Funds for the Central Universities(No.FRF-TP-16-060A1)Natural Science Foundation of Guangdong Province(No.2020A1515011197).
文摘Achieving high catalytic performance with lower possible cost and higher energetic efficiency is critical for catalytic oxidation of volatile organic compounds(VOCs).However,traditional thermocatalysts generally undergo low catalytic activity and fewer active sites.Herein,this paper synthesizes nearly all-surface-atomic,ultrathin two-dimensional(2D)Co_(3)O_(4) nanosheets to address these problems through offering a numerous active sites and high electron mobility.The 2D Co_(3)O_(4) nanosheets(1.70 nm)exhibit catalyzation to the total oxidation of n-hexanal at the lower temperature of r90%=202℃,and at the space velocity of 5.0×10^(4) h^(-1).It is over 1.2 and 6 times higher catalytic activity than that of 2D CoO nanosheets(1.71 nm)and bulk Co_(3)O_(4) counterpart,respectively.Transient absorption spectroscopy analysis shows that the oxygen vacancy defect traps electrons,thereby preventing the recombination with holes,increasing the lifetime of electrons,and making electron-holes reach a nondynamic equilibrium.The longer the electron lifetime is,the easier the oxygen vacancy defects capture electrons.Furthermore,the defects combine with oxygen to form active oxygen components.Compared with the lattice oxygen involved in the reaction of bulk Co_(3)O_(4),the nanosheets change the catalytic reaction path,which effectively reduces the activation energy barrier from 34.07 to 27.15 kJ/mol.The changed surface disorder,the numerous coordinatively-unsaturated Co atoms and the high ratio of O_(ads)/O_(lat) on the surface of 2D Co_(3)O_(4) nanosheets are responsible for the catalytic performance.
