APPLIED CATALYSIS A-GENERAL
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2011
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IF 3.384
Hua Yang,Jia-Qi Chen,Jun Li,Ying Lv,Shuang Gao
Hydroxylation of benzene to phenol in the [(CH 3 ) 4 N] 4 PMo 11 VO 40 /ascorbic acid/TEMPO/O 2 catalytic system was carefully investigated. UV–vis, ESR and 1 H NMR studies showed ascorbic acid radicals were formed through the hydrogen exchange of ascorbic acid with TEMPO (2,2,6,6-tetramethyl-1-piperidine-N-oxyl radicals) during the reaction. In acetonitrile, the ascorbic acid would be partly oxidized to 2-hydroxy-2-buten-4-olide (α-tetronic acid, isotetronic acid, compound 1 ) without TEMPO. The interaction of TEMPO and ascorbic acid restrained the oxidative dissociation of ascorbic acid and promoted the rate of the hydroxylation. Aqueous acetic acid solvent can also restrain the oxidative dissociation of ascorbic acid. In aqueous acetic acid, the yield of phenol could reach 18.9% in the [(CH 3 ) 4 N] 4 PMo 11 VO 40 /ascorbic acid/TEMPO/O 2 catalytic system with sufficient ascorbic acid after 400 min.
研究领域:
催化化学
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有机化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
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2024
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IF 11.2
Shuang Zhou,Da Wen,Wei Zhong,Jianjun Zhang,Yaorong Su,Aiyun Meng
The effective adsorption of oxygen (O 2 ) molecules over photocatalysts is a critical step in promoting the performance of photocatalytic H 2 O 2 production. However, g-C 3 N 4 usually features a Yeager-type (side-on) adsorption configuration of O 2 molecules, which causes the breaking of O–O bonds and severely hinders the H 2 O 2 production activity. Herein, we synthesized an oxygen-vacancy-rich TiO 2– x /g-C 3 N 4 step-scheme (S-scheme) heterojunction to regulate the oxygen adsorption configuration and improve the 2e – ORR selectivity of H 2 O 2 production. In-situ X-ray photoelectron spectroscopy (in-situ XPS) and density functional theory (DFT) calculations reveal that the S-scheme heterojunction is formed between TiO 2– x and g-C 3 N 4 . The difference between their Fermi levels leads to the electron flow from g-C 3 N 4 to TiO 2– x , which increases the electron-deficient sites in g-C 3 N 4 . As a result, the cleavage of O–O bonds on the surface of g-C 3 N 4 is avoided and the oxygen adsorption configuration is tuned from Yeager-type to Pauling-type (end-on). Consequently, the photocatalytic H 2 O 2 production rate is dramatically improved to 1780.3 μmol h –1 , which is about 5 times higher than that of pristine g-C 3 N 4 . This work paves a new way to tailor the oxygen adsorption configuration by rationally designing S-scheme heterojunction photocatalysts.
研究领域:
材料科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
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2020
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IF 8.758
Yuehan Cao,Ruiyang Zhang,Qian Zheng,Wen Cui,Yang Liu,Kaibo Zheng,Fan Dong,Ying Zhou
The photocatalytic performance of two-dimensional materials is largely limited by the fast recombination of photogenerated charges. Herein, we design and fabricate a novel g-C3N4/BO0.2N0.8 van der Waals heterostructure to realize oriented charge flow in-plane and separation within the interface. On one hand, a B–C bond forms within the g-C3N4/BO0.2N0.8 interface after the introduction of O atoms. The B–C bond as the mediator bridges g-C3N4 and BO0.2N0.8 sides to enhance the effective separation of photogenerated charges. On the other hand, the existence of O atoms promotes the formation of a B–O–O–B intermediate to realize that molecular oxygen can directionally obtain electrons from the surface to generate •O2–. As a result, BO0.2N0.8 instead of g-C3N4 is considered to be the main reaction side, and the energy barrier of NO3– generation is significantly decreased. The NO removal performance of g-C3N4/BO0.2N0.8 is enhanced and the NO2 generation is effectively controlled compared with that of g-C3N and g-C3N4/BN. This work could provide an effective and facile strategy to tune oriented charge transfer.
研究领域:
材料科学
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环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Shanli Wang,Mingyan Zhang,Chao Li,Licong Xu,Wenbin Jiang,Deyou Yu,Minghua Wu,Bin Yu
Manipulating the electron density of active sties to develop highly efficient catalysts is expected to be one of the most ideal approaches to facilitate overall efficiency of the heterogenous catalytic ozonation (HCO) process. In this study, we demonstrate a fluorine-doping engineering to optimize the HCO activity of aluminum oxide through an improved sol–gel method using NH 4 F (NF-Al 2 O 3 ) and HF (HF-Al 2 O 3 ) as the fluorine source. We provide evidence that the fluorine atom is successfully incorporated into crystal structure of NF-Al 2 O 3 via the formation of Al-F-Al bonds, accompany with the generation of oxygen vacancy defects , which allow for ozone molecule adsorption and activation. In contrast, the fabricated HF-Al 2 O 3 only features the presence of Al x F y ·nH 2 O instead of Al-F-Al structure probably due to the unexpected etching reaction. The introduction of fluorine atom largely decreases the local electron density of neighboring Al of NF-Al 2 O 3 catalyst evidenced by the two-fold increment in the amount of strong Lewis acid sites. Consequently, the HCO activity of NF-Al 2 O 3 catalyst is found promotion by 42.9% over pure Al 2 O 3 in terms of the degradation kinetic rate constant ( k obs ). The NF-Al 2 O 3 catalyst exhibits a powerful capacity to selectively catalyze ozone molecule into singlet oxygen ( 1 O 2 ), rendering the HCO system with high-tolerance to coexisting water matrixes (e.g., humic acid, chlorine ions, carbonate). Moreover, NF-Al 2 O 3 initiated HCO system can effectively purify wastewaters from textile industry with high-quality enough to be reused for textile dyeing. Therefore, our study provides a novel strategy to develop effective HCO catalysts for promoting wastewater treatment and reuse.
研究领域:
环境科学
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催化
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水处理
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2022
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IF 4.598
Qiong Liu,Kaiyue Hu,Yuqi She,Yufang Hu
Cancer cells require higher ROS levels to maintain their growth state of rapid division and spread·H 2 O 2 , as a kind of usual ROS molecule, is monitored by designing a new in-situ growth G4-nanowire-driven electrochemical biosensor, which is further used for probing H 2 O 2 released by rat astroglioma cell. In this process, the electrocatalytic performance to H 2 O 2 of G4-nanowire (containing G-quadruplex/hemin nanostructures) is employed as signal output, which is constructed by terminal deoxynucleotidyl transferase (TdT)-mediated polymerization in the dNTPs pool of dTTP and dGTP (4: 6). Then, the method is applied for H 2 O 2 monitoring in the range of 0.0003 ∼ 6 mM and the detection limit is estimated to be 0.075 μM (S/N = 3). More importantly, the content of H 2 O 2 generated in rat astroglioma cell is also calculated roughly, displaying an excellent feasibility for the related physiological and pathological studies. Later, TdT activity and its inhibitors are also probed orderly, and a wide linear range is presented with a detection limit of 0.81 mU/mL. It is hoped that the designed platform will provide a reference for exploring new ways to continuous dynamic surveillance of diseases in diagnosis and treatment stage.
研究领域:
分析化学
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生物化学
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癌症研究
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分子生物学
✓ 已验证
DOI
高影响因子
Nature Communications
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2024
·Vol. 15
·期 1
·1-11
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IF 14.7
Fang Cheng-Dong,Huang Ying,Sun Yi-Fan,Sun Peng-Fei,Li Ke,Yao Shu-Yang,Zhang Min-Yi,Fang Wei-Hui,Chen Jia-Jia
Understanding the Li-ions conduction network and transport dynamics in polymer electrolyte is crucial for developing reliable all-solid-state batteries. In this work, advanced nano- X-ray computed tomography combined with Raman spectroscopy and solid state nuclear magnetic resonance are used to multi-scale qualitatively and quantitatively reveal ion conduction network of poly(ethylene) oxide (PEO)-based electrolyte (from atomic, nano to macroscopic level). With the clear mapping of the microstructural heterogeneities of the polymer segments, aluminium-oxo molecular clusters (AlOC) are used to reconstruct a high-efficient conducting network with high available Li-ions (76.7%) and continuous amorphous domains via the strong supramolecular interactions. Such superionic PEO conductor (PEO-LiTFSI-AlOC) exhibites a molten-like Li-ion conduction behaviour among the whole temperature range and delivers an ionic conductivity of 1.87 × 10 −4 S cm −1 at 35 °Ϲ. This further endows Li electrochemical plating/stripping stability under 50 μA cm −2 and 50 μAh cm −2 over 2000 h. The as-built Li|PEO-LiTFSI-AlOC|LiFePO 4 full batteries show a high rate performance and a capacity retention more than 90% over 200 cycling at 250 μA cm −2 , even enabling a high-loading LiFePO 4 cathode of 16.8 mg cm −2 with a specific capacity of 150 mAh g −1 at 50 °Ϲ.
研究领域:
材料科学
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电化学
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电池技术
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高分子科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DYES AND PIGMENTS
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2025
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IF 4.2
Weilong Du,Jie Ren,Haonan Hu,Yan Zhao,Lei Cao,Dongjun Wang,Xiangkui Ren
In recent years, non-traditional intrinsic luminophores (NTILs) have garnered significant attention due to their ability to produce bright fluorescence after simple treatments. In this study, by employing a straightforward methodology of oxygen purging and controlled thermal treatment (40–120 °C), we demonstrated that non-traditional small-molecule amines (mainly diethylenetriamine, DETA) can exhibit rare dual fluorescence characteristics, including excitation-independent (EIF) and excitation-dependent (EDF) behaviors. More importantly, through structure characterization, fluorescence lifetime analysis, and simulation calculations, we confirmed the following structure-mechanism relationship underlying DETA luminescence: when pure DETA molecules were heated within the 40–80 °C, a stable dimeric structure (DETA-dimers) formed through hydrogen-bond interactions resulted in fluorescence centers exhibiting EIF characteristics. Notably, when the temperature increased further (80–120 °C), DETA-dimers in their excited state interact with oxygen molecules under external light, which formed dynamic excimers through space conjugation, denoted as [DETA-dimer … O 2 ], resulting in EDF phenomenon. Finally, capitalizing on DETA dual fluorescence properties, we successfully implemented EIF-based ion detection and EDF-enabled fluorescence staining applications. Consequently, this work advanced the mechanistic understanding of NTILs' intrinsic luminescence and established a framework for optimizing their performance in high-sensitivity fluorescence imaging and probe development.
研究领域:
材料科学
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物理化学
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有机化学
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荧光光谱学
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分析化学
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生物成像
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传感技术
✓ 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）