UiO-66-NH2, as typical visible light responsive Zr-based metal-organic frameworks (MOFs), has attracted great interest in recent years. However, rapid combination of the photoinduced carriers limits its further applic...UiO-66-NH2, as typical visible light responsive Zr-based metal-organic frameworks (MOFs), has attracted great interest in recent years. However, rapid combination of the photoinduced carriers limits its further application. Here, we designed a facile precipitation-photoreduction method to post-synthetically decorate Ag/AgCl on the surface of UiO-66-NH2 and form a heterostructure. Metallic Ag can not only transmit electrons between UiO-66-NH2 and AgCl but also absorb visible light, because of the surface plasmon resonance (SPR) effect. The rhodamine B photodegradation rate of UiO-66-NH2/Ag/AgCl (16.2 wt.% Ag) is about 10 and 4 times those of UiO-66-NH2 and Ag/AgCl, respectively. The SPR effect of Ag NPs and the formation of a heterostructure synergistically increase the absorbability of visible light, accelerate the separation of photoinduced charges, and promote the formation of superoxide radicals. We expect that our work could provide a new viewpoint for constructing efficient MOF-based photocatalytic systems.展开更多
A method for computing the visible regions of free-form surfaces is proposed in this paper. Our work is focused on accurately calculating the visible regions of the sequenced rational Bézier surfaces forming a so...A method for computing the visible regions of free-form surfaces is proposed in this paper. Our work is focused on accurately calculating the visible regions of the sequenced rational Bézier surfaces forming a solid model and having coincident edges but no inner-intersection among them. The proposed method calculates the silhouettes of the surfaces without tessellating them into triangle meshes commonly used in previous methods so that arbitrary precision can be obtained. The computed sil- houettes of visible surfaces are projected onto a plane orthogonal to the parallel light. Then their spatial relationship is applied to calculate the boundaries of mutual-occlusion regions. As the connectivity of the surfaces on the solid model is taken into account, a surface clustering technique is also employed and the mutual-occlusion calculation is accelerated. Experimental results showed that our method is efficient and robust, and can also handle complex shapes with arbitrary precision.展开更多
A simple and efficient method for the synthesis of 2-sulfonylquinoline from deoxygenative C2-sulfonylation of quinoline N-oxides with sulfinic acid induced by visible light is presented.This protocol shows a broad sub...A simple and efficient method for the synthesis of 2-sulfonylquinoline from deoxygenative C2-sulfonylation of quinoline N-oxides with sulfinic acid induced by visible light is presented.This protocol shows a broad substrate scope,and desired products with various substituents can be formed in moderate to high yields at room temperature.展开更多
The geometries of azobenzene compounds are optimized with B3LYP/6-311G* method, and analyzed with nature bond orbital, then their visible absorption maxima are calculated with TD-DFT method and ZINDO/S method respecti...The geometries of azobenzene compounds are optimized with B3LYP/6-311G* method, and analyzed with nature bond orbital, then their visible absorption maxima are calculated with TD-DFT method and ZINDO/S method respectively. The results agree well with the observed values. It was found that for the calculation of visible absorption using ZINDO/S method could rapidly yield better results by adjusting OWFπ-π (the relationship between π-π overlap weighting factor) value than by the TD-DFT method. The method of regression showing the linear relationship between OWFπ-π and BLN-N (nitrogen-nitrogen bond lengths) as OWFπ-π=?8.1537+6.5638BLN-N, can be explained in terms of quantum theory, and also be used for prediction of visible absorption maxima of other azobenzne dyes in the same series. This study on molecules’ orbital geometry indicates that their visible ab- sorption maxima correspond to the electron transition from HOMO (the highest occupied molecular orbital) to LUMO (the lowest unoccupied molecular orbital).展开更多
An efficient and sustainable protocol for regioselective hydrocarboxylation of alkynes to construct diverse propionic acid derivatives is disclosed.Under photoinduced conditions,the anti-Markovnikov hydrocarboxylation...An efficient and sustainable protocol for regioselective hydrocarboxylation of alkynes to construct diverse propionic acid derivatives is disclosed.Under photoinduced conditions,the anti-Markovnikov hydrocarboxylation of alkynes was realized with CO_(2) radical anion in-situ generated from formate as both a carbonyl source and a reductant.The collaboration between photosensitizer and hydrogen atom transfer catalyst promoted the catalytic cycle to work smoothly,giving a broad substrate scope including terminal and internal alkynes.The Giese radical addition of CO_(2) radical anion to the C—C triple bond is the key step to initiate the reaction.展开更多
基金supported by the National Natural Science Foundation of China(21676182)the National Basic Research Program of China(973 Program,2014CB932403)the Program for Introducing Talents of Discipline to Universities of China(B06006)
文摘UiO-66-NH2, as typical visible light responsive Zr-based metal-organic frameworks (MOFs), has attracted great interest in recent years. However, rapid combination of the photoinduced carriers limits its further application. Here, we designed a facile precipitation-photoreduction method to post-synthetically decorate Ag/AgCl on the surface of UiO-66-NH2 and form a heterostructure. Metallic Ag can not only transmit electrons between UiO-66-NH2 and AgCl but also absorb visible light, because of the surface plasmon resonance (SPR) effect. The rhodamine B photodegradation rate of UiO-66-NH2/Ag/AgCl (16.2 wt.% Ag) is about 10 and 4 times those of UiO-66-NH2 and Ag/AgCl, respectively. The SPR effect of Ag NPs and the formation of a heterostructure synergistically increase the absorbability of visible light, accelerate the separation of photoinduced charges, and promote the formation of superoxide radicals. We expect that our work could provide a new viewpoint for constructing efficient MOF-based photocatalytic systems.
基金Project supported by the National Basic Research Program (973) of China (No. 2002CB312106) and the National Natural Science Foundation of China (Nos. 60533070, and 60403047). The third author was supported by the project sponsored by a Foundation for the Author of National Excellent Doctoral Dissertation of China (No. 200342) and a Program for New Century Excellent Talents in Uni-versity (No. NCET-04-0088), China
文摘A method for computing the visible regions of free-form surfaces is proposed in this paper. Our work is focused on accurately calculating the visible regions of the sequenced rational Bézier surfaces forming a solid model and having coincident edges but no inner-intersection among them. The proposed method calculates the silhouettes of the surfaces without tessellating them into triangle meshes commonly used in previous methods so that arbitrary precision can be obtained. The computed sil- houettes of visible surfaces are projected onto a plane orthogonal to the parallel light. Then their spatial relationship is applied to calculate the boundaries of mutual-occlusion regions. As the connectivity of the surfaces on the solid model is taken into account, a surface clustering technique is also employed and the mutual-occlusion calculation is accelerated. Experimental results showed that our method is efficient and robust, and can also handle complex shapes with arbitrary precision.
基金supported by the National Natural Science Foundation of China (21402103, 21772107)the China Postdoctoral Science Foundation (150030)+1 种基金the Research Fund of Qingdao Agricultural University’s Highlevel Person (631303)Shandong province key research and development plan(GG201809130228)~~
文摘A simple and efficient method for the synthesis of 2-sulfonylquinoline from deoxygenative C2-sulfonylation of quinoline N-oxides with sulfinic acid induced by visible light is presented.This protocol shows a broad substrate scope,and desired products with various substituents can be formed in moderate to high yields at room temperature.
文摘The geometries of azobenzene compounds are optimized with B3LYP/6-311G* method, and analyzed with nature bond orbital, then their visible absorption maxima are calculated with TD-DFT method and ZINDO/S method respectively. The results agree well with the observed values. It was found that for the calculation of visible absorption using ZINDO/S method could rapidly yield better results by adjusting OWFπ-π (the relationship between π-π overlap weighting factor) value than by the TD-DFT method. The method of regression showing the linear relationship between OWFπ-π and BLN-N (nitrogen-nitrogen bond lengths) as OWFπ-π=?8.1537+6.5638BLN-N, can be explained in terms of quantum theory, and also be used for prediction of visible absorption maxima of other azobenzne dyes in the same series. This study on molecules’ orbital geometry indicates that their visible ab- sorption maxima correspond to the electron transition from HOMO (the highest occupied molecular orbital) to LUMO (the lowest unoccupied molecular orbital).
文摘An efficient and sustainable protocol for regioselective hydrocarboxylation of alkynes to construct diverse propionic acid derivatives is disclosed.Under photoinduced conditions,the anti-Markovnikov hydrocarboxylation of alkynes was realized with CO_(2) radical anion in-situ generated from formate as both a carbonyl source and a reductant.The collaboration between photosensitizer and hydrogen atom transfer catalyst promoted the catalytic cycle to work smoothly,giving a broad substrate scope including terminal and internal alkynes.The Giese radical addition of CO_(2) radical anion to the C—C triple bond is the key step to initiate the reaction.
