Catalysis Science & Technology
·
2020
·Vol. 10
·期 6
·1609-1618
·
IF 5.721
Chao Zhang,Jiandong Liu,Xingliang Liu,Shiai Xu
Two novel covalent bond photocatalysts, namely, g-C3N4NSs/TC1 and g-C3N4NSs/TC2 were prepared for the first time via the generation of an amide covalent bond between g-C3N4 nanosheets (g-C3N4NSs) and acyl chloride synthesized from triphenylamine-type dyes, 2-cyano-3-(4-(diphenylamino)phenyl)acrylic acid (TC1) or 3,3′-(4,4′-(phenylazanediyl)bis(4,1-phenylene))bis(2-cy-anoacrylic acid) (TC2). The experimental results indicated that triphenylamine D–π–A-type organic dye moieties covalently bonded to g-C3N4 successfully and the spectral response regions of both g-C3N4NSs/TC1 and g-C3N4NSs/TC2 could be extended from ∼460 nm to more than 600 nm. Due to the introduced amide covalent bond, the constructed g-C3N4NSs/TC1 photocatalyst showed remarkably enhanced H2 evolution activity with about 73 555.8 μmol h−1 g−1 and exhibited high apparent quantum yields (AQY) of 35.2%, 27.1%, 16.9% and 5.4% at 420 nm, 500 nm, 520 nm and 600 nm monochromatic light, respectively. Compared with the results for pure g-C3N4 NSs, about 100 times higher H2 production rate and 978 times higher AQY value were obtained for g-C3N4NSs/TC1 with the amide covalent bond under visible light irradiation. Compared to g-C3N4NSs/TC1, g-C3N4NSs/TC2 exhibited slightly lower H2 evolution activity with about 70 986.8 μmol h−1 g−1. Combining the experimental and density functional theory (DFT) calculation results, a possible mechanism can be conjectured that the electronic and geometric structures of g-C3N4NSs/TC1 are more conducive to the charge separation and the unidirectionality of electron transport in the excited state than those of g-C3N4NSs/TC2. The research reveals that this introduction of simple triphenylamine-type dyes into the surface of g-C3N4via covalent links results in a strong covalent interaction between functionalized moieties and g-C3N4 to synergistically improve the electronic and optical properties and photocatalytic performance. The present work highlights the potential use of organic dye covalent-functionalized g-C3N4via post modification as a novel photocatalyst in applications such as H2 production.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2023
·
IF 5.9
Yidong Liu,Weipeng Chen,Heng Liu,Jiangrong Luo,Li Zhao,Jisheng Zhang,Huayu Wang,Jing-Wu Wu,Jun-Li Feng,Yongxiang Zhu,Wan-Yi Tan,Tingting Cui,Yonggang Min
Polyimide (PI) possesses multiple advantages including excellent thermal stability, mechanical property and chemical resistance, which has been considered as one of the promising candidates for high-performance electrical insulation materials. Optimizing the polymer structure such as extending the band gap can yield high intrinsic breakdown strength, attributed to the inhibition of impact ionization. However, in most cases, large band gap is achieved at the cost of reducing the backbone coplanarity and rigidity or the intermolecular interaction, resulting in undesirable thermal and mechanical performance. Herein, we introduce an effective strategy to produce thermally stable and mechanically strong polyimide insulation with high breakdown strength through introducing aromatic donor groups into the main chains to construct a D−π−A structure. On the one hand, the formation of D−A effect increases the materials polarization and enhances dipole-induced scattering. On the other hand, enhanced intermolecular interaction via π−π stacking decreases free volume in PIs. Then, increased conjugation degree of the backbone and high packing density between the polymer chains benefit to thermal stability and mechanical properties. Based on this strategy, N -arkyl carbazole groups are preferred, in which the soft alkyl side groups can occupy the pores between the polymer chains to further decrease free volume. As a result, we afford polyimide insulation with significantly improved breakdown strength from 291 kV mm −1 to 570−632 kV mm −1 , as compared to the reference PI ODA-PMDA. Simultaneously, the resultant PIs, such as PI-Bu, preserve high T d5% above 524 ℃, high T g above 364 ℃ and tensile strength above 80 MPa.
研究领域:
材料科学
·
电气工程
✓ 已验证
DOI
高影响因子
ANALYTICAL CHEMISTRY
·
2022
·
IF 8.008
Xinyi Yang,Zhenzhen Cai,Dezhong Li,Da Lei,Yushu Li,Guangfa Wang,Jun Zhang,Xincun Dou
Although a set of functional molecules with the D-π-A structure has been explored as optical probes for the detection of target analytes, it remains a great challenge to elaborately design a single probe for distinguishing different analytes by their intrinsic oxidation or reduction capabilities and thus to generate distinct optical responses. Here, a unique TCF-based probe (DMA-CN) containing two unsaturated double bonds in the π-conjugation bridge and TCF with different reaction activities that could be cut off by KMnO4 and NaClO in varying degrees was developed, causing remarkably distinguishable responses for both fluorescence and colorimetric channels to discriminate KMnO4 and NaClO from each other. The fluorescence and colorimetric limits of detection (LODs) of the proposed DMA-CN toward KMnO4 were calculated as 60 and 91 nM, respectively, while those for NaClO were 13.3 and 214 nM, and all the optical signal change can be observed within 1 s with good specificity. Based on the proposed probe design strategy, a well-fabricated test strip was proven to be promising for the rapid, in-field detection and risk management. We expect that the present probe design methodology would provide a powerful strategy for efficient probe exploration, especially for discriminating the substances with similar oxidizing properties.
研究领域:
分析化学
·
生物传感
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 47
·37574-37580
·
IF 3.84
Chao-Feng Du,Lei Jiang,Lei Sun,Nian-Yu Huang,Wei-Qiao Deng
We synthesized a D–π–A–π–A type dye and demonstrated its application in dye-sensitized solar cells (DSSCs). This D–π–A–π–A type dye, named C321, consisted of a triphenylamine as a donor, a 3,4-ethylenedioxythiophene (EDOT) as a π-bridge, and a benzothiazole (BTDA)–phenyl-cyanoacrylic acid as an A–π–A group. Compared with DSSCs based on a traditional D–π–A type dye C311, the DSSCs based on C321 exhibited a significant enhancement of cell performance. A power conversion efficiency of 8.2% was achieved for DSSCs based on C321, which was 9 times higher than that for DSSCs based on C311 (0.9%). The theoretical calculations and electrochemical impedance spectroscopy investigations revealed the mechanism of the enhancement of cell performance.
研究领域:
材料科学
·
能源技术
·
有机化学
✓ 已验证
DOI
高影响因子
ANALYST
·
2020
·Vol. 145
·期 20
·6579-6585
·
IF 3.978
Guanglei Lv,Yunze Xu,Jiajia Yang,Wenhui Li,Chunxia Li,Anyang Sun
Aberrant accumulation of Amyloid-β (Aβ) peptide is closely related to Alzheimer's disease. Thus, it is important to develop featured probes for the specific detection of Aβ species. Herein, we designed and synthesized a novel near-infrared fluorescent probe SDPY based on the D–π-A architecture for the detection of Aβ aggregates. The probe SDPY displayed higher affinity for Aβ40 aggregates over Aβ42 aggregates in solution (Kd = 164 nM vs. 2.1 μM). In addition, SDPY showed excellent anti-interference against a wide range of other substances. Furthermore, SDPY was capable of labeling Aβ40 aggregates better than Aβ42 aggregates in the brain sections of AD transgenic mouse models.
研究领域:
神经科学
·
化学
·
生物化学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymer Chemistry
·
2019
·Vol. 10
·期 21
·2706-2715
·
IF 4.76
Yongjie Yuan,Lifang He,Jindi Li,Hailiang Zhang
A series of luminescent side chain polymers containing a D–π-A structure and different flexible spacer lengths, namely, poly[(Z)-ω-(4-(1-cyano-2-(4-cyanophenyl)vinyl)phenoxy)alkyl methacrylate]s (PMmPVPCN, m = 2, 4, 6, 8), were successfully prepared. With the combination of aggregation-induced emission enhancement (AIEE) luminogens and mesogens, the resultant polymers are expected to possess both liquid crystal characteristics and AIEE characteristics. The phase structure of PMmPVPCN was explored by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and one-dimensional wide-angle X-ray diffraction (1D WAXD). Photophysical properties of PMmPVPCN were studied by UV spectra and fluorescence spectra. Test results suggested that the phase structure of PMmPVPCN transformed from the amorphous phase (PMmPVPCN, m = 2, 4) to the nematic phase (PMmPVPCN, m = 6, 8) with the increase of polymer spacer length. All the synthetic monomers and polymers exhibited AIEE properties and the luminescence behavior of PMmPVPCN was associated with their chemical structure. The solid fluorescence quantum yields of PMmPVPCN increased from 22.4% to 42.7% with increasing spacer length. The polymer films also showed reversible fluorescence photo-responsive properties. The emission color and the emission intensity of polymer films changed when exposed to a 365 nm UV lamp. The change process was reversible and they could turn back to their original state when irradiated with a 254 nm UV lamp or heated at higher temperature.
研究领域:
材料科学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Wuyan Hou,Lichao Li,Chang Liu,Boying Ding,Jiahao Cui,Longni Chen,Yuan Qiu,Zhiqiang Jiao,Juan Zhang,Shougen Yin,Xiaoming Wu
As an essential component in blue perovskite light-emitting diodes (PeLEDs), functionally tailored hole transport materials (HTMs) play a decisive role in reducing the hole injection barrier, mitigating interfacial defects, and thus enhancing device performance. Herein, we report two solution-processable D-π-A hemicyanine dyes, which exhibit asymmetric/symmetric configurations and contain electron-withdrawing groups and Lewis base donors. As multifunctional HTMs, two dyes not only present high hole mobilities with improved energy level alignment in PeLEDs, but also enable the perovskite defects passivation and n phases manipulation. Interestingly, the symmetric dye achieves dual-channel hole injection and multisite anchoring for the quasi-2D perovskite (PEACsPbBr2.1Cl0.9). The passivated perovskite film forms an augmented distribution of large n phases and suppressed small n phases, thereby promoting radiative exciton recombination. Consequently, symmetric dye-treated PeLED exhibits an impressive blue electroluminescence (EL) with a maximum luminance reaching 5842 cd m–2, a peak external quantum efficiency (EQE) of 13.71% and an improved operational half lifetime (T50) of 6.7 min at 100 cd m–2, demonstrating its performance advantages over the reported PEACsPb(BrxCl1–x)3 PeLEDs. This work provides an innovative perspective for designing multifunctional HTMs by conformation engineering and gains insight into the interfacial contact for high performance perovskite optoelectronics.
研究领域:
材料科学
·
光电子学
·
纳米技术
·
应用物理学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2018
·
IF 2.011
Yi-bao Jiang,Chao Gao,Xian Zhang,Jin-shui Yao,Qin-ze Liu,Xiao-xia Cai
A novel triphenylamine derivative, 4,4′ -bis-([1,10]phenanthrolin-2-yl) imidazo -triphenylamine (IPTPA) with an A-π-D-π-A structure, has been synthesized and characterized. The UV absorption , single and two-photon fluorescence spectra showed that IPTPA was highly sensitive to Ag + with a lower detection limit of 3.97 nmoL/L and a moderate binding constant of 2.16 × 10 5 /M at room temperature . The two-photon active cross-section of IPTPA was calculated with a value of 94.68 GM at 800 nm in the tris-HCl buffer solution. The binding mechanism between IPTPA and Ag + were explored by the Job plot, ESI-MS and 1 H NMR. The A-π-D-π-A structure of IPTPA was substituted by the A-π-D-π-D structure of IPTPA-Ag to improve the fluorescence. Furthermore, the fluorescence microscopy images indicated that IPTPA could detect Ag + in living cells.
研究领域:
分析化学
·
材料科学
·
生物医学工程
·
光学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）