CHINESE JOURNAL OF CHEMICAL PHYSICS
·
2022
·Vol. 35
·期 5
·747-753
·
IF 1.09
Li Xiuhua,Wang Xueli,Lv Meng,Zhou Zhongneng,Pan Haifeng,Chen Jinquan
1,3,5-Triazine molecules represent a class of molecules that may have been prebiotic information carriers in a primordial soup in early Earth and their excited state dynamics has received attention in recent years. In our previous study, one component with lifetime longer than 100 ps was discovered in 2-amino-1,3,5-trainzine (2-AT), but its nature has not been revealed. In this study, excited state dynamics of 2-AT is studied in different solvents by using femtosecond time-resolved transient absorption and fluorescence up-conversion spectroscopy. Interestingly, an equilibrium state consisting of the bright ππ ∗ and dark n π ∗ states in 2-AT is directly observed in aqueous solution and its dynamics is solvent sensitive. The whole picture of the excited state deactivation mechanism of 2-AT is proposed based on our spectroscopy results.
研究领域:
生物化学
·
光化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2013
·Vol. 3
·期 33
·13782-13788
·
IF 2.562
Zhongfu An,Qingyang Wu,Jianjian Xiao,Runfeng Chen,Jun Yin,Huifang Shi,Ye Tao,Yang Wang,Zhixiang Wang,Huanhuan Li,Hongmei Zhang,Xinhui Zhou,Yi Zhao,Wei Huang
A series of ternary asymmetric triazines with tunable singlet and triplet excited states were successfully synthesized on the basis of σ-spacer methodology and a facile synthetic route. The optoelectronic properties are dominated by the conjugated donor–acceptor (D–A) backbone of peripheral carbazoles (D) and triazine core (A), and can be further modulated via the partially interrupted conjugation between the core and the third substituents by the σ spacers of N–CH3, NH, O, S and OSO, which offers new opportunities to fine tune the electronic structures and properties of triazines.
研究领域:
有机化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2015
·
IF 2.353
Chenchen Zhang,Shan Jiang,Kun Li,Mei Wang,Rongrong Zhu,Xiaoyu Sun,Qingxiu Wang,ShiLong Wang
The excited triplet state of tanshinone I (Tan I) extracted from the traditional Chinese medicine Salvia miltiorrhiza Bunge was characterized by laser flash photolysis. The synergic effect of Tan I on the phototherapy of cancer cells with curcumin (Cur) was also investigated by MTT assay because the excited energy transfer from the triplet state of Tan I ( 3 Tan I ∗ ) to Cur occurred. At the same time, the characteristic absorption spectra of 3 Tan I ∗ were recorded, and its molar absorption coefficient and rate constants for several excited energy transfers were obtained. The photo-therapeutic effect of Cur is enhanced by combination with Tan I.
研究领域:
药理学
·
肿瘤学
·
光化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2017
·
IF 3.012
Ailing Han,Yayu Yang,Qiang Zhang,Qingxia Tu,Guozhen Fang,Jifeng Liu,Shuo Wang,Rui Li
The electrochemistry and electrochemiluminescence (ECL) of copper metal cluster were studied in this work. The redox behavior observed was originated from the couples of Cu 8 + /Cu 8 2 + , Cu 8 /Cu 8 2 + , Cu 8 /Cu 8 + at the cluster metal core. ECL light emissions were observed under both annihilation and tripropylamine co-reactant conditions and only one excited state was involved in this ECL process and this excited state was also at the metal core. Theoretical investigation found that this excitation corresponds to an electron transfer from the metal core to the ligands. And the energy released from excited sate was approximate to the LUMO → HOMO gap energy of the cluster.
研究领域:
分析化学
·
电化学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2023
·
IF 8.8
Yudan Liu,Jingke Wu,Nanchunxiao Cheng,Pengfei Gan,Yunyi Li,Wen Liu,Jiangyu Ye,Meiping Tong,Jialiang Liang
Vacuum ultraviolet (VUV) based advanced oxidation processes (AOPs) recently attracted widespread interests. However, the role of UV 185 in VUV is only considered to be generating a series of active species, while the effect of photoexcitation has long been overlooked. In this work, the role of UV 185 induced high-energy excited state for the dephosphorization of organophosphorus pesticides was studied using malathion as a model. Results showed malathion degradation was highly related to radical yield, while its dephosphorization was not. It was UV 185 rather than UV 254 or radical yield that was responsible for malathion dephosphorization by VUV/persulfate. DFT calculation results demonstrated that the polarity of P-S bond was further increased during UV 185 excitation, favoring dephosphorization while UV 254 did not. The conclusion was further supported by degradation path identification. Moreover, despite the fact that anions (Cl - , SO 4 2 - and NO 3 - ) considerably affected radical yield, only Cl - and NO 3 - with high molar extinction coefficient at 185 nm significantly affected dephosphorization. This study shed light on the crucial role of excited states in VUV based AOPs and provided a new idea for the development of mineralization technology of organophosphorus pesticides.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULAR PHYSICS
·
2024
·
IF 1.6
Gang Wang,Lina Ding,Yang Liu,Yonggang Yang,Yufang Liu
2-(2'-Hydroxyphenyl) benzimidazole (HBI) and its derivatives are widely used in fluorescent probes, luminescent materials, and other sensing materials. In this study, the time-resolved fluorescence behaviour, and excited-state dynamics of HBI and 2-phenyl-1H-benzo[d]imidazole (BI) were studied using femtosecond transient absorption (fs-TA) spectroscopy. The stimulated emission (SE) and excited-state absorption signals of the BI molecule were located at 355 and 437 nm, respectively. For HBI, these signals were located at 475 and 384 nm, respectively. The SE signals of the BI and HBI molecules in their fs-TA spectra were consistent with the experimental short-wave fluorescence at 340 and 460 nm, respectively, in the steady-state spectra. The long-wave signal of HBI at 475 nm indicates its dual fluorescence, which may be caused by proton transfer or conformational torsion after photoexcitation. The large theoretical energy barrier of 40.97 kcal/mol in first excited (S1) state of HBI excludes the latter hypothesis. Additionally, the small energy barrier (1.88 kcal/mol) in the S1 state confirmed the excited-state intramolecular proton transfer (ESIPT). This indicates that ESIPT induces dual fluorescence behaviour of the HBI molecule, which was also demonstrated by the infrared spectra, theoretical fluorescence peaks, and molecular orbitals.
研究领域:
光化学
·
物理化学
·
理论化学
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 17
·7982-7989
·
IF 2.7
Naitian Zhang,Yuehui Li,Wenzhe Shang,Wei Liu,Xusheng Cheng,Suchan Song,Xuedan Song,Yantao Shi,Ce Hao
In this paper, we investigated the role of excited-state hydrogen bonding in the photocatalytic carbon dioxide reduction reaction (CO2RR) utilizing Rose Bengal as a catalyst, through a combined experimental and theoretical approach. Experiments validated the successful conversion of CO2 to CO in a homogeneous aqueous solution system under light irradiation, without additional photosensitizers or sacrificial agents. Theoretically, the DFT/TDDFT calculations modeled the catalyst-reactants as a hydrogen-bonded complex (HBC), understanding the energy, hydrogen, and electron transfer mechanisms induced by excited-state hydrogen bonding. Combining the photophysical and photochemical insights revealed the complete catalytic cycle, identifying the water oxidation process as the rate-limiting step in the entire photocatalytic CO2RR process. Experimental and computational results provide molecular-level insights into the structure–activity relationships. This work enhances comprehension of the pivotal role of excited-state hydrogen bonding and holds significant reference value for enhancing the conversion efficiency in the photocatalytic CO2RR.
研究领域:
物理化学
·
理论计算化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2025
·
IF 4.2
Yizhi Shao,Dandan Liu,Qinwei Xia,Zhendong Song,Wei Chen,Ke Sun,Changjiang Zhou,Yangyang Xu,Tao Gong
The elongation of π-conjugation could efficiently enhance the photophysical performances or photochemical reactivties of organic molecules, which adapts to the requests of both designing fluorescent materials and organic photoinitiators (PIs). However, there is no work attempted to design organic PIs with large molar extinction coefficients and long π-conjugation lengths by using hybridized local and charge-transfer (HLCT) method, which is meaningful to obtain high-performance PIs with significant fluorescence/photoluminence properties. What's more, how to overcome the obstacles derived from the unbalance between high triplet concentrations and photoinitiation abilities of organic PIs seems to be crucial, while PI's design from a view of excited state were rarely reported for rational regulation strategy up to now, we thus introduced four chromophores with D-A structures designed by HLCT method, whose triplet states were confirmed by Ultra-fast absorption spectroscopy, into photopolymerzation, where LEDs in various wavelengths were utilized as the light sources in the present work. Noticeably, some of these dyes could furnish high monomer conversions and rapid photopolymerization rates, not only under the irradiation of 405 nm LED, but also long-wavelength light source at 660 nm, which have been confirmed by the photopolymerization kinetics and 3D printing technique. Here, the spin-orbit coupling (SOC) coefficients were carried out as well, to examine their effects on photoinitiation abilities of investigated molecules, which can be regarded as the first attempt to achieving light-harvesting PIs from excited state design. Finally, the corresponding photochemical mechanisms were investigated by steady state photolysis, fluorescence quenching experiments, particularly by frontier orbit energy and distributions to examine the interactions between these dyes with co-initiator/additives in details.
研究领域:
材料科学
·
有机化学
✓ 已验证
产品关联
DOI
高影响因子
ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
·
2020
·
IF 2.03
Lian Wang,Song Zhang,Ye Wang,Bing Zhang
Dibenzofuran (DBF) has attracted much attention from scientists recently since it is applied as a photoluminescence material and pharmaceutically active compound. Since the polychlorinated derivatives are highly toxic and manifest photostability in the environment. Femtosecond transient absorption spectroscopy associated with quantum chemical calculations are employed to investigate the ultrafast excited state dynamics of dibenzofuran from the S 2 state in 1,4-dioxane and ethanol, respectively. Following excitation at a wavelength of 266 nm, the S 2 state is firstly populated in the Franck–Condon region and preserves the planar molecular structure of the ground state. The observed increase of the transient absorption spectra of the excited state within the first several picoseconds indicates a geometry relaxation occurring on the S 2 potential energy surface. The subsequent kinetic traces of excited state absorption show that the S 2 state in the adiabatic region decays to the S 1 state through a fast internal conversion, followed by intersystem crossing to the T 1 state with a decay time of tens and hundreds of picoseconds in ethanol and 1,4-dioxane, respectively. Finally, the deactivation processes from the S 1 or T state are slow and take place on a time scale of about 20 ns.
研究领域:
化学
·
光物理学
✓ 已验证
DOI
高影响因子
Nano Research
·
2020
·Vol. 13
·期 12
·3261-3267
·
IF 8.183
Han Shenghui,Lian Gang,Zeng Xiaoliang,Cao Zhaozhen,Wang Qilong,Cui Deliang,Wong Ching-Ping
Developing metal-free and long lifetime room-temperature phosphorescence (RTP) materials has received tremendous interest due to their numerous potential applications, of which stable triplet-excited state is the core challenge. Here, boron carbon oxynitride (BCNO) dots, emitting stable blue fluorescence and green RTP, are reported for the first time. The obtained BCNO dots exhibit an unexpected ultralong RTP lifetime of 1.57 s, lasting over 8 s to naked eyes. The effective doping of carbon and oxygen elements in boron nitride (BN) actually provides a small energy gap between singlet and triplet states, facilitating the intersystem crossing (ISC) and populating of triplet excitons. The formation of compact cores via crystallization and effective inter-/intra-dot hydrogen bonds further stabilizes the excited triplet states and reduces quenching of RTP by oxygen at room temperature. Based on the water-soluble feature of BCNO dots, a novel advanced security ink is developed toward anti-counterfeiting tag and confidential information encryption. This study extends BCNO dots to rarely exploited phosphorescence fields and also provides a facile strategy to prepare ultralong lifetime metal-free RTP materials.
研究领域:
材料科学
·
光学
·
化学
✓ 已验证
DOI
高影响因子
Advanced Optical Materials
·
2021
·Vol. 9
·期 12
·2100434
·
IF 9.926
Xingwen Cheng,Renfu Li,Wei Zheng,Datao Tu,Xiaoying Shang,Zhongliang Gong,Jin Xu,Siyuan Han,Xueyuan Chen
All-inorganic lead-free metal halides doped with ns 2 -metal ions have shown great promise in optoelectronics and photovoltaics owing to their superior optical properties. Herein, a strategy is reported for tailoring the optical properties of 0D A 2 InX 5 ⋅H 2 O and A 3 InX 6 (A = Cs, Rb; X = Cl, Br) crystals via Sb 3+ doping, and the excited-state dynamics of Sb 3+ is unveiled through temperature-dependent photoluminescence (PL) and femtosecond transient absorption spectroscopies. Owing to the spatially confined 0D structure of the In-based halides, Sb 3+ ions experience a strong Jahn–Taller distortion on the excited state, which results in intense PL from Sb 3+ with a broad emission band and a large Stokes shift. Through the control of A cation and the octahedral unit, tunable Sb 3+ emissions (490−750 nm) with PL quantum yields up to 91.8% are achieved in these 0D In-based halides. These findings provide fundamental insights into the excited-state dynamics of Sb 3+ in 0D metal halides, thus laying a foundation for future design of luminescent lead-free 0D metal halides through ns 2 -metal doping towards versatile applications.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
WATER RESEARCH
·
2023
·
IF 12.8
Ruiya Zhou,Juan Liu,Chi Zhou,Xu Zhang
Lignin is a major terrestrial source of chromophoric dissolved organic matter (CDOM), and studying the phototransformation of lignin monomers and their related compounds can enhance our understanding of CDOM intramolecular interactions. Coniferyl aldehyde (Coni) and sinapaldehyde (Sina) form ground-state complexes with CDOM, with equilibrium constants of 7,800 (± 1,800) and 20,000 (± 2,000) M −1 , respectively. In comparison, vanillin (Van) exhibits minimal affinity for CDOM complexation. The bimolecular reaction rate constants between singlet oxygen ( 1 O 2 ) and these phenolic carbonyl compounds ranged from 0.46 (± 0.02) to 1.8 (± 0.1) × 10 7 M −1 s −1 , which is approximately one order of magnitude lower than their reaction rate constants (0.51 (± 0.02)–1.25 (± 0.02) × 10 8 M −1 s −1 ) with the triplet excited state of CDOM ( 3 CDOM*). In acidic CDOM solutions (pH 5.0), 1 O 2 , H 2 O 2 , and organic peroxyl radicals had negligible impact on the transformation. Comparing the initial transformation rate in the presence and in the absence of NaN 3 or furfuryl alcohol led to an overestimation of the contribution of 1 O 2 to the transformation of Van, Coni, or Sina. 3 CDOM* scavengers could not fully inhibit the transformation of Coni or Sina. The remaining transformation is considered to arise from either the unquenched intra-CDOM phase 3 CDOM* or a fraction of Coni⊂CDOM or Sina⊂CDOM complex, which underwent intramolecular photoinduced chemical reactions.
研究领域:
环境科学
·
生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）