The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wid...The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wide-spectrum ZnPc/Au-T photocatalysts.Compared with large Au NP(8 nm)-mediated ZnPc/Au-T photocatalyst,ultrasmall Au NP(3 nm)-mediated one shows advantageous photoactivity,achieving 3-and 10-fold CO_(2)conversion rates compared with reference ZnPc/T and pristine TiO_(2)nanosheets,respectively.Employing monochromatic beam-assisted surface photovoltage and photocurrent action,etc.,the introduction of ultrasmall Au NPs more effectively facilitates intrinsic interfacial charge transfer.Moreover,ZnP c molecules are found more dispersed with the existence of small Au NPs hence exposing abundant Zn^(2+)sites as the catalytic center for CO_(2)reduction.This work provides a feasible design strategy and renewed recognition for supported MPc-based photocatalyst systems.展开更多
lmprovement of the charge separation of titanosilicate molecular sieves is critical to their use asphotocatalysts for oxidative organic transformations.In this work,MFI TS-1 molecular sievenanosheets(TS-1 NS)were synt...lmprovement of the charge separation of titanosilicate molecular sieves is critical to their use asphotocatalysts for oxidative organic transformations.In this work,MFI TS-1 molecular sievenanosheets(TS-1 NS)were synthesized by a low-temperature hydrothermal method using a tai-lored diquaternary ammonium surfactant as the structure-directing agent.Introducing Ni^2+cationsat the ion-exchange sites of the TS-1 NS framework significantly enhanced its photoactivity in aero-bic alcohol oxidation.The optimized Ni cation-functionalized TS-1 NS(Ni/TS-1 NS)provide impres-sive photoactivity,with a benzyl alcohol(BA)conversion of 78.9%and benzyl aldehyde(BAD)se-lectivity of 98.8%using O as the only oxidant under full light irradiation;this BAD yield is approx-imately six times greater than that obtained for bulk TS-1,and is maintained for five runs.The ex-cellent photoactivity of Ni/TS-1 NS is attributed to the significantly enlarged surface area of thetwo-dimensional morphology TS-1 NS,extra mesopores,and greatly improved charge separation.Compared with bulk TS-1,Ni/TS-1 NS has a much shorter charge transfer distance.Theas-introduced Ni species could capture the photoelectrons to further improve the charge separa-tion.This work opens the way to a class of highly selective,robust,and low-cost titanosilicate mo-lecular sieve-based photocatalysts with industrial potential for selective oxidative transformationsand pollutant degradation.展开更多
Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrat...Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrated that a large amount of 1 O_(2) is produced on pristine graphitic carbon nitride(CN) nanosheet compared with bismuth oxybromide(BiOBr) and comme rcial P25 titanium dioxide(TiO_(2)).This leads to a certain photoactivity of CN for MPS oxidation.The observed ~77% selectivity for CN depends on the competitive results of excitonic energy transfer for 1 O_(2) formation and charge carrier separation for superoxide radical(O_(2)·) production,which are based on the phosphorescence spectra and electron paramagnetic resonance signals,respectively.Moreover,ultrathin CN nanosheets are synthesized by thermal treatment with the cyanuric acid-melamine hydrogen bonded aggregates as precursors.It is confirmed that the amount of produced 1 O_(2) could be increased by decreasing the thickness of resultant CN nanosheets.The optimized ultrathin CN nanosheet(~4 nm) exhibits excellent photoactivity with high selectivity(~99%).It is suggested that the excitonic energy transfer for 1 O_(2) formation is close related to the intrinsic exciton binding energy and the two-dimensional quantum confinement effect.This work establishes a basic mechanistic understanding on the excitonic processes in CN,and develops a feasible route to design CN-based photocatalysts for efficient 1 O_(2) generation.展开更多
Myocardial infarction is a devastating disease worldwide.At present,nearly 40 million patients suffer from heart failure.Owing to a lack of adequate blood supply,25%of cardiomyocytes are subjected to apoptosis and nec...Myocardial infarction is a devastating disease worldwide.At present,nearly 40 million patients suffer from heart failure.Owing to a lack of adequate blood supply,25%of cardiomyocytes are subjected to apoptosis and necrosis within a few hours after infarction.It remains challenging to find effective therapeutic methods for heart failure.On the other hand,zebrafish and neonatal mouse hearts have a strong ability to regenerate(Poss et al.,2002;Raya et al.,2003;Porrello et al.,2011),and their regeneration derives from existing cardiomyocytes(Jopling et al.,2010;Kikuchi et al..展开更多
基金supported by the National Natural Science Foundation of China(Nos.U2102211 and 22378101)the Fundamental Research Foundation for Universities of Heilongjiang Province(No.2021-KYYWF-0004)the Science Fund for Distinguished Young Scholars of Heilongjiang University(No.JCL202102)。
文摘The interface modulation significantly affects the photocatalytic performances of supported metal phthalocyanines(MPc)-based systems.Herein,ZnPc was loaded on nanosized Au-modified TiO_(2)nanosheets(Au-T)to obtain wide-spectrum ZnPc/Au-T photocatalysts.Compared with large Au NP(8 nm)-mediated ZnPc/Au-T photocatalyst,ultrasmall Au NP(3 nm)-mediated one shows advantageous photoactivity,achieving 3-and 10-fold CO_(2)conversion rates compared with reference ZnPc/T and pristine TiO_(2)nanosheets,respectively.Employing monochromatic beam-assisted surface photovoltage and photocurrent action,etc.,the introduction of ultrasmall Au NPs more effectively facilitates intrinsic interfacial charge transfer.Moreover,ZnP c molecules are found more dispersed with the existence of small Au NPs hence exposing abundant Zn^(2+)sites as the catalytic center for CO_(2)reduction.This work provides a feasible design strategy and renewed recognition for supported MPc-based photocatalyst systems.
文摘lmprovement of the charge separation of titanosilicate molecular sieves is critical to their use asphotocatalysts for oxidative organic transformations.In this work,MFI TS-1 molecular sievenanosheets(TS-1 NS)were synthesized by a low-temperature hydrothermal method using a tai-lored diquaternary ammonium surfactant as the structure-directing agent.Introducing Ni^2+cationsat the ion-exchange sites of the TS-1 NS framework significantly enhanced its photoactivity in aero-bic alcohol oxidation.The optimized Ni cation-functionalized TS-1 NS(Ni/TS-1 NS)provide impres-sive photoactivity,with a benzyl alcohol(BA)conversion of 78.9%and benzyl aldehyde(BAD)se-lectivity of 98.8%using O as the only oxidant under full light irradiation;this BAD yield is approx-imately six times greater than that obtained for bulk TS-1,and is maintained for five runs.The ex-cellent photoactivity of Ni/TS-1 NS is attributed to the significantly enlarged surface area of thetwo-dimensional morphology TS-1 NS,extra mesopores,and greatly improved charge separation.Compared with bulk TS-1,Ni/TS-1 NS has a much shorter charge transfer distance.Theas-introduced Ni species could capture the photoelectrons to further improve the charge separa-tion.This work opens the way to a class of highly selective,robust,and low-cost titanosilicate mo-lecular sieve-based photocatalysts with industrial potential for selective oxidative transformationsand pollutant degradation.
基金NSFC(Nos.U1805255,11804086,21706044,21971057)General Financial Grant from the China Postdoctoral Science Foundation(No.2017M621316)+2 种基金the Natural Science Foundation of Heilongjiang Province,China(No.B2017006)the General Financial Grant from the Postdoctoral Science Foundation of Heilongjiang Province,China(No.LBHZ17187)the General Financial Grant from Heilongjiang Province for returned students from overseas in 2018。
文摘Efficient generation of singlet oxygen(1 O_(2)) by an excitonic ene rgy transfer process is highly desired on a semiconductor photocatalyst for selective oxidation of methyl phenyl sulfide(MPS).Herein,it is demonstrated that a large amount of 1 O_(2) is produced on pristine graphitic carbon nitride(CN) nanosheet compared with bismuth oxybromide(BiOBr) and comme rcial P25 titanium dioxide(TiO_(2)).This leads to a certain photoactivity of CN for MPS oxidation.The observed ~77% selectivity for CN depends on the competitive results of excitonic energy transfer for 1 O_(2) formation and charge carrier separation for superoxide radical(O_(2)·) production,which are based on the phosphorescence spectra and electron paramagnetic resonance signals,respectively.Moreover,ultrathin CN nanosheets are synthesized by thermal treatment with the cyanuric acid-melamine hydrogen bonded aggregates as precursors.It is confirmed that the amount of produced 1 O_(2) could be increased by decreasing the thickness of resultant CN nanosheets.The optimized ultrathin CN nanosheet(~4 nm) exhibits excellent photoactivity with high selectivity(~99%).It is suggested that the excitonic energy transfer for 1 O_(2) formation is close related to the intrinsic exciton binding energy and the two-dimensional quantum confinement effect.This work establishes a basic mechanistic understanding on the excitonic processes in CN,and develops a feasible route to design CN-based photocatalysts for efficient 1 O_(2) generation.
基金supported by grants from the National Natural Science Foundation of China(Nos.31730061,81870198 and 31821091)the National Key R&D Program of China(2018YFA080050 and 2019YFA0801602)
文摘Myocardial infarction is a devastating disease worldwide.At present,nearly 40 million patients suffer from heart failure.Owing to a lack of adequate blood supply,25%of cardiomyocytes are subjected to apoptosis and necrosis within a few hours after infarction.It remains challenging to find effective therapeutic methods for heart failure.On the other hand,zebrafish and neonatal mouse hearts have a strong ability to regenerate(Poss et al.,2002;Raya et al.,2003;Porrello et al.,2011),and their regeneration derives from existing cardiomyocytes(Jopling et al.,2010;Kikuchi et al..
