O644.1 99021395偶氮苯的同步辐射光电离研究=Photoionizationstudies of azobenzene using synchrotron radiation[刊,中]/盛六四,武国华,陈韦,高辉,张允武(中国科技大学国家同步辐射实验室.安徽,合肥(230029))∥光学学报.—1998,1...O644.1 99021395偶氮苯的同步辐射光电离研究=Photoionizationstudies of azobenzene using synchrotron radiation[刊,中]/盛六四,武国华,陈韦,高辉,张允武(中国科技大学国家同步辐射实验室.安徽,合肥(230029))∥光学学报.—1998,18(6).—828-831用同步辐射光电离质谱与符合技术相结合测定了偶氮苯光电离效率谱,获得了该分子的电离势,导出了分子和分子离子中某些键的解离能以及自由基C<sub>6</sub>H<sub>5</sub>N<sub>2</sub>的电离势。测得了不同光子能量激发下的质谱图,并对不同能量时偶氮苯的解离电离方式进行了分析。图2表1参6(严寒)O644.1 99021396SO<sub>2</sub>与甲苯的气相光化学反应=Photochemical reactionsof sulfur dioxide and toluene[刊。展开更多
Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells (DSSCs). The DSSCs incorporating ...Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells (DSSCs). The DSSCs incorporating tris(1,10-phenanthroline)eobalt(Ⅱ/Ⅲ)-based redox elec- trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the w-conjugated spacers of organic dyes upon the photovoltage and photocur- rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination.展开更多
The allyl radical has been observed in a low-pressure premixed gasoline/oxygen/argon flame by using tunable vacuum ultraviolet photoionization mass spectrometry, The ionization potential of the allyl radical is derive...The allyl radical has been observed in a low-pressure premixed gasoline/oxygen/argon flame by using tunable vacuum ultraviolet photoionization mass spectrometry, The ionization potential of the allyl radical is derived to be (8.13 ±0.02) eV from photoionization efficiency curve, In addition, a high level ab initzo Gaussian-3 (G3) method was used to calculate the energies of tile radical and its cation. The calculated adiabatic ionization potential is 8.18 eV, which is in excellent agreement with the experimental value. The result is helpful for identifying the allyl radical formed from other flames and for understanding the mechanism of soot formation.展开更多
Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from ...Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.展开更多
Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting beca...Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting because of its appropriate band structure,non-toxicity,high stability,and low cost.Nevertheless,its relatively low photochemical conversion efficiency limits its application,and enhancing its PEC water splitting efficiency remains a challenge.Consequently,increasing efforts have been rendered toward improving the performance of hematite photoanodes.The entire PEC water splitting efficiency typically includes three parts:the photon absorption efficiency,the separation efficiency of the semiconductor bulk,and the surface injection efficiency.This review briefly discusses the recent advances in studies on hematite photoanodes for water splitting,and through the enhancement of the three above-mentioned efficiencies,the corresponding strategies toward improving the PEC performance of hematite are comprehensively discussed and summarized.展开更多
Two-dimensional(2D)Dion-Jacobson(D-J)-type cesium lead iodide CsPbI_(3) perform remarkably in terms of stability.However,the complex interactions between spacer and inorganic layers limit its excellent progress in per...Two-dimensional(2D)Dion-Jacobson(D-J)-type cesium lead iodide CsPbI_(3) perform remarkably in terms of stability.However,the complex interactions between spacer and inorganic layers limit its excellent progress in perovskite solar cells(PSCs).Herein,starting from the considerable structural diversity of organic spacers,we engineer 2D CsPbI_(3) with fine-tuning functionalities.Specifically,for the first time we embedded fluorinated aromatic cations in 2D D-J CsPbI_(3),and successfully applied it into construction of high-performance PSCs.Compared with constitutive 1,4-diaminobenzene(PDA),the fluorinated 2-fluorobenzene-1,4-diamine(F-PDA)component greatly expands the dipole moment from 0.59 D to 3.47 D,which reduces the exciton binding energy of the system.A theoretical study shows that the spacer layer and inorganic plane are more enriched with charge accumulation in(F-PDA)Csn±1 Pb_(n)I_(3n+1).The results show that(F-PDA)Csn±1Pb_(n)I_(3n+1) demonstrates more significant charge transfer between organic and inorganic layers than(PDA)Csn±1 Pb_(n)I_(3n+1),and it is confirmed in the femtosecond transient absorption experiment.Moreover,the interactions of the fluorinated spacer with the[PbI_(6)]_(4)-plane effectively manipulate the crystallization quality,and thus the ion migration and defect formation of target 2D CsPbI_(3) are inhibited.As a result,we obtained a record power conversion efficiency(PCE)beyond 15%for 2D D-J(F-PDA)Cs_(3)Pb_(4)I_(13)(n=4)PSCs with significantly improved environmental stability compared with the three-dimensional(3D)counterparts.展开更多
文摘O644.1 99021395偶氮苯的同步辐射光电离研究=Photoionizationstudies of azobenzene using synchrotron radiation[刊,中]/盛六四,武国华,陈韦,高辉,张允武(中国科技大学国家同步辐射实验室.安徽,合肥(230029))∥光学学报.—1998,18(6).—828-831用同步辐射光电离质谱与符合技术相结合测定了偶氮苯光电离效率谱,获得了该分子的电离势,导出了分子和分子离子中某些键的解离能以及自由基C<sub>6</sub>H<sub>5</sub>N<sub>2</sub>的电离势。测得了不同光子能量激发下的质谱图,并对不同能量时偶氮苯的解离电离方式进行了分析。图2表1参6(严寒)O644.1 99021396SO<sub>2</sub>与甲苯的气相光化学反应=Photochemical reactionsof sulfur dioxide and toluene[刊。
基金This work was supported by the National Natu- ral Science Foundation of China (No.21072152 and No.21101115).
文摘Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells (DSSCs). The DSSCs incorporating tris(1,10-phenanthroline)eobalt(Ⅱ/Ⅲ)-based redox elec- trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the w-conjugated spacers of organic dyes upon the photovoltage and photocur- rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination.
基金This work Was supported by the Knowledge Innovation funding of CAS and the Natural Science Foundation of China(NSFC No.20473081).
文摘The allyl radical has been observed in a low-pressure premixed gasoline/oxygen/argon flame by using tunable vacuum ultraviolet photoionization mass spectrometry, The ionization potential of the allyl radical is derived to be (8.13 ±0.02) eV from photoionization efficiency curve, In addition, a high level ab initzo Gaussian-3 (G3) method was used to calculate the energies of tile radical and its cation. The calculated adiabatic ionization potential is 8.18 eV, which is in excellent agreement with the experimental value. The result is helpful for identifying the allyl radical formed from other flames and for understanding the mechanism of soot formation.
基金supported by the National Natural Science Foundation of China(51572253,21771171)Scientific Research Grant of Hefei National Synchrotron Radiation Laboratory(UN2017LHJJ)+1 种基金the Fundamental Research Funds for the Central Universitiescooperation between NSFC and Netherlands Organization for Scientific Research(51561135011)~~
文摘Photocatalytic H2 evolution reactions on pristine graphitic carbon nitrides(g-C3N4),as a promising approach for converting solar energy to fuel,are attractive for tackling global energy concerns but still suffer from low efficiencies.In this article,we report a tractable approach to modifying g-C3N4 with vanadyl phthalocyanine(VOPc/CN)for efficient visible-light-driven hydrogen production.A non-covalent VOPc/CN hybrid photocatalyst formed viaπ-πstacking interactions between the two components,as confirmed by analysis of UV-vis absorption spectra.The VOPc/CN hybrid photocatalyst shows excellent visible-light-driven photocatalytic performance and good stability.Under optimal conditions,the corresponding H2 evolution rate is nearly 6 times higher than that of pure g-C3N4.The role of VOPc in promoting hydrogen evolution activity was to extend the visible light absorption range and prevent the recombination of photoexcited electron-hole pairs effectively.It is expected that this facile modification method could be a new inspiration for the rational design and exploration of g-C3N4-based hybrid systems with strong light absorption and high-efficiency carrier separation.
文摘Photoelectrochemical(PEC)water splitting is one of the most promising approaches toward achieving the conversion of solar energy to hydrogen.Hematite is a widely applied photoanode material in PEC water splitting because of its appropriate band structure,non-toxicity,high stability,and low cost.Nevertheless,its relatively low photochemical conversion efficiency limits its application,and enhancing its PEC water splitting efficiency remains a challenge.Consequently,increasing efforts have been rendered toward improving the performance of hematite photoanodes.The entire PEC water splitting efficiency typically includes three parts:the photon absorption efficiency,the separation efficiency of the semiconductor bulk,and the surface injection efficiency.This review briefly discusses the recent advances in studies on hematite photoanodes for water splitting,and through the enhancement of the three above-mentioned efficiencies,the corresponding strategies toward improving the PEC performance of hematite are comprehensively discussed and summarized.
基金supported by the National Natural Science Foundation of China(52073131,51902148,and 12047501)the Fundamental Research Funds for the Central Universities(lzujbky-2021-it31,lzujbky-2021-59,lzujbky-2021-ct15,lzujbky2021-ct01,and lzujbky-2021-sp69)supported by Supercomputing Center of Lanzhou University。
文摘Two-dimensional(2D)Dion-Jacobson(D-J)-type cesium lead iodide CsPbI_(3) perform remarkably in terms of stability.However,the complex interactions between spacer and inorganic layers limit its excellent progress in perovskite solar cells(PSCs).Herein,starting from the considerable structural diversity of organic spacers,we engineer 2D CsPbI_(3) with fine-tuning functionalities.Specifically,for the first time we embedded fluorinated aromatic cations in 2D D-J CsPbI_(3),and successfully applied it into construction of high-performance PSCs.Compared with constitutive 1,4-diaminobenzene(PDA),the fluorinated 2-fluorobenzene-1,4-diamine(F-PDA)component greatly expands the dipole moment from 0.59 D to 3.47 D,which reduces the exciton binding energy of the system.A theoretical study shows that the spacer layer and inorganic plane are more enriched with charge accumulation in(F-PDA)Csn±1 Pb_(n)I_(3n+1).The results show that(F-PDA)Csn±1Pb_(n)I_(3n+1) demonstrates more significant charge transfer between organic and inorganic layers than(PDA)Csn±1 Pb_(n)I_(3n+1),and it is confirmed in the femtosecond transient absorption experiment.Moreover,the interactions of the fluorinated spacer with the[PbI_(6)]_(4)-plane effectively manipulate the crystallization quality,and thus the ion migration and defect formation of target 2D CsPbI_(3) are inhibited.As a result,we obtained a record power conversion efficiency(PCE)beyond 15%for 2D D-J(F-PDA)Cs_(3)Pb_(4)I_(13)(n=4)PSCs with significantly improved environmental stability compared with the three-dimensional(3D)counterparts.