A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carr...A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carried out in gram scale.Various radical sources,including trifluoromethyl radical,thiocyanate radical,bromide radical,chlorine radical could partici-pate effectively instead of azide radical in the reaction.展开更多
A new radical-mediated method for the synthesis of 1-(2-(1,2-diarylvinyl)phenyl)ethan-1-ones by the redox hydroarylation of o-(hydroxyalkyl)arylalkynes with arylsulfonyl chlorides is described. This visible light cata...A new radical-mediated method for the synthesis of 1-(2-(1,2-diarylvinyl)phenyl)ethan-1-ones by the redox hydroarylation of o-(hydroxyalkyl)arylalkynes with arylsulfonyl chlorides is described. This visible light catalysis method proceeds via a sequence of the radical addition of aryl group across the C?C triple bond, protonation and redox reaction, and represents a new redox transformation reaction directed by a neighboring hydroxyl group.展开更多
The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to ...The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production.展开更多
The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation pr...The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.展开更多
Photocatalytic technology has attracted much attention in the fields of clean energy and environmental governance.However,how to design and develop highly efficient photocatalytic materials remains an urgent scientifi...Photocatalytic technology has attracted much attention in the fields of clean energy and environmental governance.However,how to design and develop highly efficient photocatalytic materials remains an urgent scientific problem to be solved.This study focuses on enhancing photocatalytic activity through microstructure modification.Among them,ToRed-4 showed the most prominent performance.Under the illumination condition of 420 nm,its value was 13506 lmol g^(-1) h^(-1),which was approximately 18 times that of CN550(bulk g-C_(3)N_(4))(719 lmol g^(-1) h^(-1)).By using DFT calculations,the photocatalytic performance was deeply analyzed,revealing the significant advantages of the ToRed series in key performance indicators and the underlying synergy mechanisms,including the reduction of the HOMO-LUMO energy gap,the efficient separation of electron holes,the expansion of the electronic transition range,the transformation of the electrostatic potential distribution,the increase in dipole moment,and the optimization of the Coulomb attractive energy.The research results of this study provide a key basis for opening up new avenues for the design and development of highly efficient photocatalytic materials and are expected to play an important role in related fields.展开更多
A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive ...A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive alkanes and cyclic ethers as alkylation reagents,and phenanthrenequinone(PQ)as a direct hydrogen-atom transfer(HAT)photocatalyst.The desired products were obtained in moderate to good yields at room temperature under air.展开更多
We have constructed a novel porous pyrene-based organic cage,PyTC1,through the condensation reaction of cyclohexanediamine with 5,5′-(pyrene-1,6-diyl)diisophthalaldehyde.Single-crystal X-ray diffraction analysis reve...We have constructed a novel porous pyrene-based organic cage,PyTC1,through the condensation reaction of cyclohexanediamine with 5,5′-(pyrene-1,6-diyl)diisophthalaldehyde.Single-crystal X-ray diffraction analysis reveals the effective intercage C–H...πinteraction between cyclohexanediimine and pyrene segments.Such a soft intercage C–H...πinteraction,rather than a classic J-aggregate with slippedπ–π-stacking configuration,induced an unusual bathochromic shift of pyrene-based chromophore absorption from an ultraviolet region of PyTC1 in solution to the visible light region of PyTC1 in solid-state.展开更多
The rational design of photocatalyst that can effectively reduce CO_(2) under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsc...The rational design of photocatalyst that can effectively reduce CO_(2) under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch reaction.In this work,we synthesized a series of CeO_(2)-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO_(2) reduction.It was found that the selectivity and productivity of CO and H_(2) from photoreduction of CO_(2) in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H_(2) ratio can be widely tunable from 1/7.7 to 1/1.3.Furthermore,compared with LDH,Ce-0.15 also drove photocatalytic CO_(2) to syngas under 600 nm irradiation.It implied that an optimum amount of CeO_(2) modifying LDH promoted the photoreduction of CO_(2) to syngas.This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation.展开更多
Carbon quantum dots(CQDs)are receiving increasing attention for their excellent photostability,low toxicity,and tunable fluorescence performance,but it is still challenging to prepare full-spectrum CQDs using only one...Carbon quantum dots(CQDs)are receiving increasing attention for their excellent photostability,low toxicity,and tunable fluorescence performance,but it is still challenging to prepare full-spectrum CQDs using only one single set of precursor and solvent.In this study,P and N co-doped carbon dots(N,PR-CQDs)with multi-color-emissive tunable fluorescence from blue to green and orange were synthesized from bio-based chitosan,employing phosphoric acid as solvent and dopant.The introduction of phosphoric acid successfully shortens the manufacturing reaction time,and the heteratomic functional groups of P–O/P=O on surface of carbon dots enrich the surface defect states,promoting n–π*transition,and therefore changing their electron structure/energy level to reduce the band gap,thus facilitating emission at long wavelength.Specifically,increasing phosphoric acid concentration leads to characteristic excitation peaks red shift from 320 to 420 nm with the characteristic emission peaks red shift from 406 to 503 nm.A new emission peak at 610 nm appears,enabling N,PR-CQDs exhibit double emission peaks with fluorescence color from green to yellow to orange.After compositing with carbon nitride(g-C3N4),N,PR-CQDs work as photosensitizer and effectively narrow the energy gap(Eg)of g-C3N4 from 2.75 to 2.40 eV,endowing the photocatalyst higher visible light capture ability and broader light response region.The photocatalytic degradation rate of rhodamine B(RhB)under visible light irradiation reaches up to 98.39%within 60 min using N,P20%-CQDs/g-C3N4 as catalyst,which is 1.4 times that of pure g-C3N4,and it is demonstrated that·O2−is the major active substance contributing for RhB degradation by de-ethyl and aromatic ring breakage.展开更多
文摘A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carried out in gram scale.Various radical sources,including trifluoromethyl radical,thiocyanate radical,bromide radical,chlorine radical could partici-pate effectively instead of azide radical in the reaction.
基金supported by the National Natural Science Foundation of China(2140204621172060+1 种基金21472039)the Fundamental Research Funds for the Central Universities
文摘A new radical-mediated method for the synthesis of 1-(2-(1,2-diarylvinyl)phenyl)ethan-1-ones by the redox hydroarylation of o-(hydroxyalkyl)arylalkynes with arylsulfonyl chlorides is described. This visible light catalysis method proceeds via a sequence of the radical addition of aryl group across the C?C triple bond, protonation and redox reaction, and represents a new redox transformation reaction directed by a neighboring hydroxyl group.
文摘The construction of S‐scheme heterojunction photocatalysts has been regarded as an effective avenue to facilitate the conversion of solar energy to fuel.However,there are still considerable challenges with regard to efficient charge transfer,the abundance of catalytic sites,and extended light absorption.Herein,an S‐scheme heterojunction of 2D/2D zinc porphyrin‐based metal‐organic frameworks/BiVO_(4)nanosheets(Zn‐MOF/BVON)was fabricated for efficient photocatalytic CO_(2)conversion.The optimal one shows a 22‐fold photoactivity enhancement when compared to the previously reported BiVO4 nanoflake(ca.15 nm),and even exhibits~2‐time improvement than the traditional g‐C3N4/BiVO4 heterojunction.The excellent photoactivities are ascribed to the strengthened S‐scheme charge transfer and separation,promoted CO_(2)activation by the well‐dispersed metal nodes Zn_(2)(COO)_(4)in the Zn‐MOF,and extended visible light response range based on the results of the electrochemical reduction,electron paramagnetic resonance,and in‐situ diffuse reflectance infrared Fourier transform spectroscopy.The dimension‐matched Zn‐MOF/BVON S‐scheme heterojunction endowed with highly efficient charge separation and abundant catalytic active sites contributed to the superior CO2 conversion.This study offers a facile strategy for constructing S‐scheme heterojunctions involving porphyrin‐based MOFs for solar fuel production.
文摘The visible‐light photoredox‐catalyzed carboxylation of benzyl chlorides and bromides with CO_(2) has been reported.With inexpensive organic dyes as photocatalysts and amines as electron donors,this carboxylation proceeds well in the absence of sensitive organometallic reagents,transition metal catalysts,or metallic reductants.A wide range of commercially available and inexpensive benzyl halides undergo such carboxylation to give valuable aryl acetic acids,including several pharmaceutical molecules and drug precursors,in moderate to high yields.Moreover,this reaction features mild reaction conditions(one atmospheric pressure of CO_(2) and room temperature),broad substrate scope,good functional group tolerance,easy scalability,and low catalyst loading,thus providing an efficient approach for the assembly of aryl acetic acids.
基金supported by the National Ten Thousand Talents Plan and the high-performance computing platform of Guizhou Universitythe Program of Introducing Talents to Chinese Universities(no.D20023)+1 种基金the Central Government Guides Local Science and Technology Development Fund Projects(Qiankehezhongyindi(2023)001)the Frontiers Science Centre for Asymmetric Synthesis and Medicinal Molecules,and the Department of Education,Guizhou Province[Qianjiaohe KY(2020)004].
文摘Photocatalytic technology has attracted much attention in the fields of clean energy and environmental governance.However,how to design and develop highly efficient photocatalytic materials remains an urgent scientific problem to be solved.This study focuses on enhancing photocatalytic activity through microstructure modification.Among them,ToRed-4 showed the most prominent performance.Under the illumination condition of 420 nm,its value was 13506 lmol g^(-1) h^(-1),which was approximately 18 times that of CN550(bulk g-C_(3)N_(4))(719 lmol g^(-1) h^(-1)).By using DFT calculations,the photocatalytic performance was deeply analyzed,revealing the significant advantages of the ToRed series in key performance indicators and the underlying synergy mechanisms,including the reduction of the HOMO-LUMO energy gap,the efficient separation of electron holes,the expansion of the electronic transition range,the transformation of the electrostatic potential distribution,the increase in dipole moment,and the optimization of the Coulomb attractive energy.The research results of this study provide a key basis for opening up new avenues for the design and development of highly efficient photocatalytic materials and are expected to play an important role in related fields.
基金supported by the Natural Science Foundation of Xinjiang Uyghur Autonomous Region(Nos.2022E01042,2022TSYCCX0024,and 2021D01E10)the NSFC(Nos.21861036,21961037 and 21762041).
文摘A metal-free visible-light-induced synthesis of aza-polycyclic aromatic hydrocarbons via cascade alkylation/cyclization of N-methacryloyl-2-phenylbenzimidazole was developed.The reaction was carried out with inactive alkanes and cyclic ethers as alkylation reagents,and phenanthrenequinone(PQ)as a direct hydrogen-atom transfer(HAT)photocatalyst.The desired products were obtained in moderate to good yields at room temperature under air.
基金support from the National Key R&D Program of China(no.2016YFC0700603)Natural Science Foundation of China(nos.21631003 and 21805005)+1 种基金the Fundamental Research Funds for the Central Universities(nos.FRF-BD-20-14A and FRF-IDRY-19-028)University of Science and Technology Beijing is gratefully acknowledged.
文摘We have constructed a novel porous pyrene-based organic cage,PyTC1,through the condensation reaction of cyclohexanediamine with 5,5′-(pyrene-1,6-diyl)diisophthalaldehyde.Single-crystal X-ray diffraction analysis reveals the effective intercage C–H...πinteraction between cyclohexanediimine and pyrene segments.Such a soft intercage C–H...πinteraction,rather than a classic J-aggregate with slippedπ–π-stacking configuration,induced an unusual bathochromic shift of pyrene-based chromophore absorption from an ultraviolet region of PyTC1 in solution to the visible light region of PyTC1 in solid-state.
基金This research was supported by the National Natural Science Foundation of China(Grant Nos.U1707603,21878008,21625101,U1507102,21922801)Beijing Natural Science Foundation(Nos.2182047,2202036)the Fundamental Research Funds for the Central Universities(Nos.XK1802-6,XK1902,12060093063,2312018RC07).
文摘The rational design of photocatalyst that can effectively reduce CO_(2) under visible light(l>400 nm),and simultaneously precise control of the products syngas(CO/H2)ratio is highly desirable for the Fischer-Tropsch reaction.In this work,we synthesized a series of CeO_(2)-decorated layered double hydroxides(LDHs,Ce-x)samples for photocatalytic CO_(2) reduction.It was found that the selectivity and productivity of CO and H_(2) from photoreduction of CO_(2) in conjunction with Ru-complex as photosensitizer performed an obvious“volcano-like”trend,with the highest point at Ce-0.15 and the CO/H_(2) ratio can be widely tunable from 1/7.7 to 1/1.3.Furthermore,compared with LDH,Ce-0.15 also drove photocatalytic CO_(2) to syngas under 600 nm irradiation.It implied that an optimum amount of CeO_(2) modifying LDH promoted the photoreduction of CO_(2) to syngas.This report gives the way to fully utilize the rare earth elements and provides a promising route to enhance the photo-response ability and charge injection efficiency of LDH-based photocatalysts in the synthesis of syngas with a tunable ratio under visible light irradiation.
基金Foundation of China(Nos.52203283 and 31700517)the Natural Science Foundation of Shandong Province(Nos.ZR2022MC040 and ZR2021QC117)the Open Project of State Key Laboratory of Supramolecular Structure and Materials(No.sklssm2022035,Jilin University)financially supported this work.
文摘Carbon quantum dots(CQDs)are receiving increasing attention for their excellent photostability,low toxicity,and tunable fluorescence performance,but it is still challenging to prepare full-spectrum CQDs using only one single set of precursor and solvent.In this study,P and N co-doped carbon dots(N,PR-CQDs)with multi-color-emissive tunable fluorescence from blue to green and orange were synthesized from bio-based chitosan,employing phosphoric acid as solvent and dopant.The introduction of phosphoric acid successfully shortens the manufacturing reaction time,and the heteratomic functional groups of P–O/P=O on surface of carbon dots enrich the surface defect states,promoting n–π*transition,and therefore changing their electron structure/energy level to reduce the band gap,thus facilitating emission at long wavelength.Specifically,increasing phosphoric acid concentration leads to characteristic excitation peaks red shift from 320 to 420 nm with the characteristic emission peaks red shift from 406 to 503 nm.A new emission peak at 610 nm appears,enabling N,PR-CQDs exhibit double emission peaks with fluorescence color from green to yellow to orange.After compositing with carbon nitride(g-C3N4),N,PR-CQDs work as photosensitizer and effectively narrow the energy gap(Eg)of g-C3N4 from 2.75 to 2.40 eV,endowing the photocatalyst higher visible light capture ability and broader light response region.The photocatalytic degradation rate of rhodamine B(RhB)under visible light irradiation reaches up to 98.39%within 60 min using N,P20%-CQDs/g-C3N4 as catalyst,which is 1.4 times that of pure g-C3N4,and it is demonstrated that·O2−is the major active substance contributing for RhB degradation by de-ethyl and aromatic ring breakage.
