PHYSICAL CHEMISTRY CHEMICAL PHYSICS
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2017
·Vol. 20
·期 4
·2205-2210
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IF 4.123
Rui-Ling Zhang,Yang Yang,Song-Qiu Yang,Ke-Li Han
Host–guest charge transfer (HGCT) plays a key role in applications from solar energy conversion to photocatalysis. Herein, a HGCT system, a pillared Pt(II) metallacage with encapsulated coronene was synthesized and the ultrafast excited-state dynamics were investigated by combination of femtosecond transient absorption spectroscopy, nanosecond transient emission spectrocopy and quantum chemistry calculations. Two significant ultrafast dynamic processes were unveiled: (i) charge transfer from a singlet local excited (1LE) state associated with the coronene moiety to a 1HGCT state with τ = 9.5 ps; and (ii) triplet–triplet energy transfer from a high 3HGCT state to a 3LE state with τ = 139.5 ps. The resulting long-lived species, the lowest 3LE and 3HGCT states eventually decay to the ground state in microsecond time scales of 5.2 and 43.4 μs respectively. Moreover, a clear mechanism depicting the main excited-state decay pathways connecting the initial photoexcited transients with the resulting species was proposed.
研究领域:
化学
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光化学
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理论计算
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材料科学
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DOI
PubMed
高影响因子
ADVANCED MATERIALS
·
2024
·Vol. 36
·期 30
·2404888
·
IF 27.4
Shen Shen,Qishan Xie,Smruti Ranjan Sahoo,Jian Jin,Glib V. Baryshnikov,Hao Sun,Hongwei Wu,Hans Ågren,Qingsong Liu,Liangliang Zhu
Confining luminophores into modified hydrophilic matrices or polymers is a straightforward and widely used approach for afterglow bioimaging. However, the afterglow quantum yield and lifetime of the related material remain unsatisfactory, severely limiting the using effect especially for deep-tissue time-resolved imaging. This fact largely stems from the dilemma between material biocompatibility and the quenching effect of water environment. Herein an in situ metathesis promoted doping strategy is presented, namely, mixing ≈10 −3 weight ratio of organic-emitter multicarboxylates with inorganic salt reactants, followed by metathesis reactions to prepare a series of hydrophilic but water-insoluble organic–inorganic doping afterglow materials. This strategy leads to the formation of edible long-afterglow photoluminescent materials with superior biocompatibility and excellent bioimaging effect. The phosphorescence quantum yield of the materials can reach dozens of percent (the highest case: 66.24%), together with the photoluminescent lifetime lasting for coupes of seconds. Specifically, a long-afterglow barium meal formed by coronene salt emitter and BaSO 4 matrix is applied into animal experiments by gavage, and bright stomach afterglow imaging is observed by instruments or mobile phone after ceasing the photoexcitation with deep tissue penetration. This strategy allows a flexible dosage of the materials during bioimaging, facilitating the development of real-time probing and theranostic technology.
研究领域:
材料科学
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生物医学工程
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DOI
PubMed
高影响因子
Nanoscale
·
2013
·Vol. 5
·期 12
·5456-5461
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IF 6.233
Tianru Wu,Guqiao Ding,Honglie Shen,Haomin Wang,Lei Sun,Yun Zhu,Da Jiang,Xiaoming Xie
In this paper, we systematically studied the effects of coronene as nucleation seeds for graphene synthesis at low temperatures by chemical vapor deposition. Naphthalene was used as a solid carbon source which is capable of producing graphene at temperatures down to 300 °C. The experimental results showed clear evidence that coronene seeds work as preferred nucleation sites, through which the nucleation density and graphene domain size could be modulated. The introduction of the seeds greatly improved the homogeneity of monolayer graphene by suppressing uncontrolled nucleation and multilayer growth of graphene domains. The obtained carrier mobility of graphene fabricated at 400 °C by the seed-assisted process reached ∼912 cm2 V−1 s−1, which is considerably higher than that of ∼300 cm2 V−1 s−1 measured on graphene prepared without seeding. Besides offering cost advantages for large scale application, the technique proposed in this study may find significant applications in graphene/copper hybrid interconnects and graphene based flexible electronics.
研究领域:
材料科学
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电子工程
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DOI
PubMed
高影响因子
Journal of Materials Chemistry C
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2017
·Vol. 5
·期 17
·4293-4301
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IF 5.256
Ying Zhao,Qiang Zhang,Ke Chen,Hongfang Gao,Honglan Qi,Xianying Shi,Yajun Han,Junfa Wei,Chengxiao Zhang
We synthesized and studied a new class of A–(π-D)3 type donor–acceptor molecular graphene, triphenothiazinyl triazacoronenes, [2,3,6,7,10,11-hexamethoxy-4,8,12-tri-(10-alkyl-phenothiazine)-1,5,9-triazacoronene] (TPTZ-TAC derivatives). These molecules have been synthesized by employing three electron-rich triphenothiazine (PTZ) groups as electron donors, which were linked to an electron acceptor of an electron-deficient triazacoronene core (2,3,6,7,10,11-hexamethoxy-1,5,9-triazacoronene, TAC). These donor–acceptor molecular graphenes exhibited unique multiple fluorescence and electro-generated chemiluminescence (ECL) emissions that are dependent on the concentration of these molecules, attributed to strong π-stacking interactions. The electrochemical behaviour showed two closely spaced consecutive reversible one-electron oxidations occurring on the PTZ groups and a reversible one-electron reduction localizing on the TAC core. The absorption and fluorescence emission spectra reveal that the electronic properties are affected by the intramolecular charge transfer (ICT) interaction from the PTZ donors to TAC acceptors in the excited state. The effect of π-stacking interaction was noticed for the excimer emission at the lower energy region. The ICT properties of the TPTZ-TACs have been analyzed by concentration-dependence and solvatochromism of fluorescence spectral studies. Remarkably, multiple ECL emissions were produced from the TPTZ-TAC derivatives via a radical ion annihilation and coreactant process through the formation of a charge-transfer excimer state. This work demonstrates that the attachment of electron-rich PTZ groups as electron donors to an electron-deficient TAC core as an electron acceptor, is a promising route to improve the optoelectronic properties of the molecular graphene TAC core. The D–A molecule excimers will represent a new approach to red luminescence and a means to enhance the fluorescence efficiency.
研究领域:
有机化学
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材料科学
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光电化学
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产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Yuanjiao Liu,Yi Wang,Songyao Zhang,Hengqi Zou,Xinrui Miao,Wenli Deng
The self-assembly of two kinds of C2-symmetric aromatic carboxylic acids named 4,4′,4″,4‴-(1,4-phenylenebis(azanetriyl))tetrabenzoic acid (H4PTA) and 5′,5″-bis(4-carboxyphenyl)-[1,1′:3′,1″:3″,1‴-quaterphenyl]-4,4‴-dicarboxylic acid (H4QDA) and the coadsorption with coronene (COR) molecules at different solution concentrations were investigated at the heptanoic acid (HA)/highly oriented pyrolytic graphite (HOPG) interface by scanning tunneling microscopy (STM). H4PTA molecules with nonplanar conformation self-assembled into a highly ordered rhombus structure at variational concentrations and subsequently could be regulated into a Kagomé network by the coadsorption of COR molecules. H4QDA molecules with planar conformation self-assembled into two various nanostructures (rhombus structure and Kagomé network) coexisting on the HOPG surface at different concentrations. The Kagomé architecture of H4QDA could act as a rigid host template to trap the COR molecules. Meanwhile, COR exhibited preferential adsorption in the porous template: COR only entered the hexagonal cavities at low concentrations and filled in all hexagonal and triangular cavities at high concentrations. Density functional theory (DFT) calculations and molecular dynamics (MD) simulations showed that the host–guest co-assembled structures were more thermodynamically and kinetically stable. The formation of different self-assembly and co-assembly processes of two molecules could be attributed to the dissimilar molecular conformation. Our work is of significance to further explore the formation mechanism of two-dimensional (2D) porous arrangements and provides an ideal way to regulate the adsorption of porous templates.
研究领域:
材料科学
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表面科学
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计算化学
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DOI
高影响因子
ACS Earth and Space Chemistry
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2022
·
IF 3.556
Yan Liu,Changmin Zhang,Kangle Ding,Zhenzhen Yu,Yi Wu
It has remained controversial throughout the last three decades whether highly mature solid bitumen derived from petroleum degradation can engage in thermochemical sulfate reduction (TSR)─an organic–inorganic interaction that occurs in sedimentary basins. To investigate the kinetic characteristics of thermal sulfate reduction by thermogenic pyrobitumen, hydropyrolysis experiments with magnesium sulfate (MgSO4) and a model compound, coronene (C24H12), were performed at 300–500 °C under controlled laboratory conditions. The experimental results indicate that detectable amounts of H2S from the designed simulation system were formed at a threshold temperature of 400 °C. Thermodynamically, coronene-initiated sulfate reduction is an exothermic process at 100–220 °C with the reaction heat of 221.0–248.3 kJ/mol hydrocarbon. TSR of coronene is characterized by a first-order reaction with an apparent activation energy of 193.0 kJ/mol. Interactions between C24H12 and MgSO4 are kinetically categorized as a slow TSR system because the high stability of coronene restricts the formation rate of H2S gas relative to rapid TSR systems containing C2+ hydrocarbons. When extrapolated to the temperature range of typical oil and gas reservoirs (100–200 °C), the reaction rate of TSR by coronene is slightly higher than that of TSR involving methane, gypsum, and MgCl2 solutions [He, K.; Zhang, S. C.; Wang, X. M. Hydrothermal experiments involving methane and sulfate: insights into carbon isotope fractionation of methane during thermochemical sulfate reduction, Org. Geochem. 2020, 149, 104107]. Depletion of some organic carbons by TSR may contribute to the increase of S/C ratios in the molecular structure of thermogenic pyrobitumen. In deep carbonate reservoirs of methane-dominated TSR, hydrothermal reduction of sulfates by thermogenic pyrobitumen most likely occurs as a less well-recognized geochemical process.
研究领域:
地质学
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地球化学
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DOI
高影响因子
CARBON
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2021
·
IF 9.594
Jian Liu,Xin Li,Lingie Zhang,Xiangyang Liu,Xu Wang
The transformation of graphene into sp 3 -bonded carbon films through ultra-high pressure, hydrogenation or fluorination has been studied for years. It is considered that only few layers of graphenes on metal surfaces can realize this transformation and the electron orbitals hybridization between metal substrate and graphene layer is thought to be the drving force and stabilize the formed sp 3 carbon structure. Here, we use nanographene molecule, hexa-peri-hexabenzocoronene (HBC), as the model compound to exploit the fluorination reaction between graphene and fluorine gas. MALDI-TOF mass, XPS and XRD results show that the direct fluorination realized the intermolecular cross-linking of nanographene molecules without the assistence of mental substrate. Combining with theoretical calculation and EPR test results, we proved that the fluorination of nanographene molecules with F 2 follows a free-radical mechanism, and the carbon radicals formed during fluorination caused the covalent cross-linking between graphene molecules which have a tight π-π stacking. Meanwhile, the fluorination of other small nanographene molecules, pyrene and perylene, further confirmed the universality of this free-radical cross-linking mechanism. This would provide a further understanding for the chemical transformation from graphene layers to 2D diamond structure under chemical adsorption process.
研究领域:
材料科学
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化学
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DOI
高影响因子
ACTA PHYSICO-CHIMICA SINICA
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2023
·
IF 10.9
Renjie Xue,Chao Ma,Jing He,Xuechao Li,Yanning Tang,Lifeng Chi,Haiming Zhang
Catassembly is a newly developed concept concerning the process of molecular assembly improved by a catalyst-assembler (catassembler). However, it has not been visualized in detail at the molecular level. To achieve the formation of highly complex structures with high efficiency and selectivity, a deeper understanding of catassembly is essential. In this study, we present the scanning tunneling microscopy (STM) characterization of a catassembly process within host-guest assembly. We utilize a metastable self-assembled network of 1,3,5-tris(4-carboxyphenyl)-benzene (BTB) at the liquid-solid interface between 1-octanoic acid and highly oriented pyrolytic graphite (HOPG). Different adsorption behaviors of low-concentration guest molecules (copper phthalocyanine (CuPc), and coronene (COR)) are contrastively analyzed during the host-guest assembly in both single-guest (COR/BTB or CuPc/BTB) and multi-guest molecule (COR&CuPc/BTB) systems. The spontaneous phase transition from a hexagonal to an oblique structure of BTB monolayers (high concentration, approximately 500 μmol∙L −1 in octanoic acid) provides an ideal metastable phase for studying the dynamic assembly process. In the host-guest assembly, the metastable BTB hexagonal phase serves as a host network and can be stabilized by co-assembling guest molecules under a negative bias voltage. However, the stability of the metastable phase varies with different guest molecules. We observe that the BTB metastable phase is more robust with COR guest molecules than with CuPc. In the CuPc/BTB system, we find that low-concentration CuPc (approximately 1.5 μmol∙L −1 in octanoic acid) can hardly co-assemble with BTB, leading to the gradual collapse of the metastable BTB networks into the oblique phase. The different stability of BTB metastable phase in the host-guest assembly is attributed to differences in the kinetics of trapping guest molecules. Guest COR molecules exhibit kinetic advantages over CuPc when assembling with host BTB networks under a negative sample bias. The lower trapping rate of CuPc hinders the formation of co-assembled BTB/CuPc networks. These differences in the dynamic behavior of the guest molecules are further explored in the research of catassembly. In a multi-guest molecule system (COR&CuPc/BTB), COR molecules are preferentially trapped by BTB hexagonal networks and can gradually be replaced by CuPc during continuous scanning. The more energetically stable structure of CuPc/BTB compared to COR/BTB rationalizes the exchange of the guest molecule and the evolution of the assembly phase. The involvement of COR significantly increases both the efficiency and quality of the CuPc/BTB assembly, serving as a catassembler. This observation provides insights into a complete catassembly process at the molecular level, enabling further investigations into the selectivity and efficiency of host-guest phenomena for potential applications in analysis and separation. Additionally, this work serves as a prototype for constructing highly complex 2D assembled monolayers. Download: Download high-res image (162KB) Download: Download full-size image
研究领域:
材料科学
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化学
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DOI
高影响因子
MICROCHIMICA ACTA
·
2018
·Vol. 185
·期 2
·1-7
·
IF 5.705
Yang Meiding,Zhou Huipeng,Zhang Yunyi,Hu Zhenzhen,Niu Niu,Yu Cong
A new water soluble fluorescent coronene probe (CTCA) was synthesized and is shown to display strong fluorescence (with excitation/emission maxima at 313/450 nm) in aqueous solution. Dopamine was oxidized under air to form polydopamine (PDA) which quenches the fluorescence of CTCA. The enzyme acetylcholinesterase (AChE) is known catalyze the hydrolysis of acetylthiocholine to produce thiocholine. Thiocholine inhibits the polymerization of DA, and this leads to recovery in CTCA fluorescence. These findings form the basis for a new method for detection of AChE activity. The assay has a detection limit as low as 0.05 mU·mL −1 of AChE. It is highly selective, and other enzymes do no noticeably interfere. It was applied to the determination of AChE activity in (spiked) human serum, and of AChE inhibitors in (spiked) lake water samples.
Controlled synthesis of polydopamine for the highly sensitive and selective sensing of AChE activity is reported for the first time.
研究领域:
分析化学
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生物化学
·
酶活性测定
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DOI
PubMed
高影响因子
Energy Technology
·
2020
·Vol. 8
·期 6
·2000223
·
IF 3.404
Yaobing Fang,Wanying Bi,Aiye Wang,Wen Zheng,Wenhui Yuan,Li Li
Dual-ion batteries with pure ionic liquid electrolyte (IL-DIBs) have received increasing interest due to their sustainability, high operating voltage, and environmental friendliness. However, owing to the insertion/extraction of large-size ionic liquid cations, the conventional IL-DIBs with a graphite anode suffer from severe volume expansion and graphite exfoliation on the anode, causing a poor cycling performance. Herein, a novel IL-DIB is constructed by introducing a bulk organic material (coronene) as the anode, against a natural graphite cathode. The results show that, in a voltage window range from 1.0 to 4.4 V, the battery has a high discharge specific capacity of ≈73.3 mA h g −1 and exhibits a good cycling performance for 450 cycles with a lower capacity loss of 0.061 mA h g −1 per cycle at a current density of 300 mA g −1 (3 C). Notably, it still maintains a considerable capacity of ≈55.8 mA h g −1 at a high rate of 10 C. In addition, the reversible intercalation/de-intercalation of the Pyr 14 + cations into/from the coronene anode is investigated by ex situ X-ray diffraction and Fourier transform infrared spectroscopy, showing an excellent structure stability of the coronene crystal during the charge–discharge process.
研究领域:
电化学
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材料科学
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能量存储
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DOI
高影响因子
Journal of Materials Chemistry B
·
2017
·Vol. 5
·期 32
·6572-6578
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IF 4.543
Meiding Yang,Huipeng Zhou,Yongxin Li,Qingfeng Zhang,Juanmin Li,Cuiyun Zhang,Chuibei Zhou,Cong Yu
A new water soluble coronene bisimide derivative (CTDI) was designed and synthesized. CTDI self-assembled in an aqueous solution and formed supramolecular nanofibers through π–π stacking and hydrophobic interactions. The nanofibers exhibit distinct peroxidase-like catalytic activity, and can catalyze the redox reaction of 3,3,5,5-tetramethylbenzidine (TMB) in the presence of hydrogen peroxide. Clear assay solution color changes were observed. The peroxidase-like catalytic property was utilized for the sensitive detection of H2O2 and glucose. The assay shows excellent sensitivity, and 1 μM of glucose could be easily detected. Glucose detection in dilute human blood samples was also demonstrated, and the results were verified using a commercial glucose meter. Our method is simple, convenient, sensitive and selective, and could facilitate the sensing of glucose in relation to biological and biomedical research applications.
研究领域:
材料科学
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分析化学
·
生物医学工程
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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）