Silver nanoparticles (Ag NPs) can effectively address the issue of antibiotic-resistant bacterial infections to reduce the potential toxicity of Ag NPs. Although challenging, it is, therefore, necessary to achieve the...Silver nanoparticles (Ag NPs) can effectively address the issue of antibiotic-resistant bacterial infections to reduce the potential toxicity of Ag NPs. Although challenging, it is, therefore, necessary to achieve the sustainable release of Ag+ ions from a finite amount of Ag NPs. This study aims at designing an efficient and benign antimicrobial silver-based ternary composite composed of photocatalysis zinc oxide (ZnO) and reduced graphene oxide (rGO) as a carrier, in which the reactive oxygen species (ROS) excited from ZnO and Ag+ ions released from the Ag NPs cooperate to realize an effective antibacterial activity against E. coli and S. aureus. The constant effective bacterial performance of the ternary photocatalyst with minimum Ag content can be attributed to the increase in the available quantity of ROS, which results from the enhanced separation efficiency of the photogenerated carriers. The proposed system notably realized the long-term sustainable release of Ag+ ions with low concentration for 30 days when compared with an equivalent amount of silver nitrate. Moreover, the use of the composite prevents biotoxicity and silver wastage, and imparts enhanced stability to the long-lasting antibacterial efficacy.展开更多
Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation effici...Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation efficiency,remain as the bottleneck to achieve highly efficient hydrogen evolution.Here,a hollow oxygen-incorporated g-C3N4 nanosheet(OCN)with an improved surface area of 148.5 m2 g^−1 is fabricated by the multiple thermal treatments under the N2/O2 atmosphere,wherein the C–O bonds are formed through two ways of physical adsorption and doping.The physical characterization and theoretical calculation indicate that the O-adsorption can promote the generation of defects,leading to the formation of hollow morphology,while the O-doping results in reduced band gap of g-C3N4.The optimized OCN shows an excellent photocatalytic hydrogen evolution activity of 3519.6μmol g^−1 h^−1 for~20 h,which is over four times higher than that of g-C3N4(850.1μmol g^−1 h^−1)and outperforms most of the reported g-C3N4 catalysts.展开更多
Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the ...Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the supports.It was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO_2and H_2in ethanol without any additives.Especially,the catalyst Pd/NC-800-6.9%containing quaternary N showed the best performance,affording a series of formylamides in good or even excellent yields.Further investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst.展开更多
Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this...Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with Cu Cl could catalyze the formylation of amines with CO_2/H_2 at 120 °C. Especially, choline imidazolate showed the best performance,affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO_2 and the synergistic effect between the IL and Cu Cl resulted in the high activity for catalysing the formylation of amines with CO_2/H_2.展开更多
Developing simple and green routes to access valuable chemicals is of significance.Herein,we present a green and novel route to synthesize N,N-dimethyl arylmethylamines(DAMAs)from hexamethylenetetramine(HMTA)and aryl ...Developing simple and green routes to access valuable chemicals is of significance.Herein,we present a green and novel route to synthesize N,N-dimethyl arylmethylamines(DAMAs)from hexamethylenetetramine(HMTA)and aryl aldehydes in the presence of hydrogen,and a series of DAMAs can be obtained in good yields.This approach opens the precedent for HMTA as N,N-dimethylamine source to synthesize chemicals with N,N-dimethylamine group,which has promising applications for N-containing chemicals synthesis.展开更多
Pyridine-containing anion-based ionic liquids(PA-ILs) with two kinds of interaction sites to bind CO_2, e.g., [P4444][2-OP], were found to be highly efficient for catalysing the cycloaddition reactions of atmospheric ...Pyridine-containing anion-based ionic liquids(PA-ILs) with two kinds of interaction sites to bind CO_2, e.g., [P4444][2-OP], were found to be highly efficient for catalysing the cycloaddition reactions of atmospheric CO_2 with epoxides at room temperature under metal-and halogen-free conditions, producing a series of cyclic carbonates in high yields. It was demonstrated that the cooperative interaction from two interaction sites in the anions of PA-ILs activated CO_2, while the cation activated the epoxides substrates via coordination to the central P+ unit, thus resulting in the high activity of the IL catalysts.展开更多
基金supported by the National Natural Science Foundation of China(51472101,51572114,21773062,21577036)the Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials(JSKC17003)~~
文摘Silver nanoparticles (Ag NPs) can effectively address the issue of antibiotic-resistant bacterial infections to reduce the potential toxicity of Ag NPs. Although challenging, it is, therefore, necessary to achieve the sustainable release of Ag+ ions from a finite amount of Ag NPs. This study aims at designing an efficient and benign antimicrobial silver-based ternary composite composed of photocatalysis zinc oxide (ZnO) and reduced graphene oxide (rGO) as a carrier, in which the reactive oxygen species (ROS) excited from ZnO and Ag+ ions released from the Ag NPs cooperate to realize an effective antibacterial activity against E. coli and S. aureus. The constant effective bacterial performance of the ternary photocatalyst with minimum Ag content can be attributed to the increase in the available quantity of ROS, which results from the enhanced separation efficiency of the photogenerated carriers. The proposed system notably realized the long-term sustainable release of Ag+ ions with low concentration for 30 days when compared with an equivalent amount of silver nitrate. Moreover, the use of the composite prevents biotoxicity and silver wastage, and imparts enhanced stability to the long-lasting antibacterial efficacy.
基金This work was supported by the National Science Foundation of China(51772152,51702129,51572114,51972150,21908110,and 51902161)Fundamental Research Funds for the Central Universities(30919011269,30919011110,and 1191030558)+3 种基金Y.W.thanks the Key University Science Research Project of Jiangsu province(16KJB430009)Y.Z.thanks for the support from the Postdoctoral Science Foundation(2018M630527)China Scholarship Council(201708320150)J.S.thanks the Natural Science Foundation of Jiangsu Province(BK20190479,1192261031693).
文摘Graphitic carbon nitride(g-C3N4)-based photocatalysts have shown great potential in the splitting of water.However,the intrinsic drawbacks of g-C3N4,such as low surface area,poor diffusion,and charge separation efficiency,remain as the bottleneck to achieve highly efficient hydrogen evolution.Here,a hollow oxygen-incorporated g-C3N4 nanosheet(OCN)with an improved surface area of 148.5 m2 g^−1 is fabricated by the multiple thermal treatments under the N2/O2 atmosphere,wherein the C–O bonds are formed through two ways of physical adsorption and doping.The physical characterization and theoretical calculation indicate that the O-adsorption can promote the generation of defects,leading to the formation of hollow morphology,while the O-doping results in reduced band gap of g-C3N4.The optimized OCN shows an excellent photocatalytic hydrogen evolution activity of 3519.6μmol g^−1 h^−1 for~20 h,which is over four times higher than that of g-C3N4(850.1μmol g^−1 h^−1)and outperforms most of the reported g-C3N4 catalysts.
基金supported by the Chinese Academy of Sciences (QYZDY-SSW-SLH013)the National Natural Science Foundation of China (21533011, 21503239)
文摘Using mesoporous N-doped carbons(NCs)derived from glucose and melamine as the supports,a series of Pd/NC catalysts were prepared,in which Pd nanoparticles with average size<2.0 nm were uniformly distributed on the supports.It was indicated that the resultant Pd/NC catalysts were effective for N-formylation of amines with CO_2and H_2in ethanol without any additives.Especially,the catalyst Pd/NC-800-6.9%containing quaternary N showed the best performance,affording a series of formylamides in good or even excellent yields.Further investigation reveals that the interaction between the Pd nanoparticles and quaternary nitrogen in the NC support was responsible for the good performance of the catalyst.
基金supported by the Chinese Academy of Sciences (QYZDY-SSW-SLH013)the National Natural Science Foundation of China (21673068, 21533011)
文摘Choline-based ionic liquids(Ch-ILs) with anions possessing interacting sites to attract CO_2 were designed, which could capture CO_2 with capacity >1.0 mol CO_2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with Cu Cl could catalyze the formylation of amines with CO_2/H_2 at 120 °C. Especially, choline imidazolate showed the best performance,affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO_2 and the synergistic effect between the IL and Cu Cl resulted in the high activity for catalysing the formylation of amines with CO_2/H_2.
基金This work was financially supported by the Beijing Municipal Science&Technology Commission(No.Z191100007219009)Chinese Academy of Sciences(Grant No.QYZDY-SSW-SLH013).
文摘Developing simple and green routes to access valuable chemicals is of significance.Herein,we present a green and novel route to synthesize N,N-dimethyl arylmethylamines(DAMAs)from hexamethylenetetramine(HMTA)and aryl aldehydes in the presence of hydrogen,and a series of DAMAs can be obtained in good yields.This approach opens the precedent for HMTA as N,N-dimethylamine source to synthesize chemicals with N,N-dimethylamine group,which has promising applications for N-containing chemicals synthesis.
基金supported by the National Natural Science Foundation of China(21403252,21533011)the Chinese Academy of Sciences(QYZDY-SSW-SLH013)
文摘Pyridine-containing anion-based ionic liquids(PA-ILs) with two kinds of interaction sites to bind CO_2, e.g., [P4444][2-OP], were found to be highly efficient for catalysing the cycloaddition reactions of atmospheric CO_2 with epoxides at room temperature under metal-and halogen-free conditions, producing a series of cyclic carbonates in high yields. It was demonstrated that the cooperative interaction from two interaction sites in the anions of PA-ILs activated CO_2, while the cation activated the epoxides substrates via coordination to the central P+ unit, thus resulting in the high activity of the IL catalysts.
