SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Meiling Wu,Yang Tao,Yuwei Liu,Sanying Hou,Tiyang Xiao,Qing Fu,Guowen Peng,Lang Shi
In this study, Fe/N co-doped graphene-like honeycomb porous carbon (Fe-NC)was produced and used for the activating PMS to degrade TC. The Fe-NC catalyst has shown high activity in the TC degradation by activated PMS, with an efficiency of up to 94 % in 30 min. while the blank catalyst without N and Fe doping exhibited the lowest performance with 47.3 % TC degradation. Moreover, other operational factors of Fe-NC catalysts were also investigated to evaluate its catalytic activity. The burst experiments and electron paramagnetic resonance (EPR) experiments demonstrated that free radical paths (O 2 ·- ) and non-free radical paths ( 1 O 2 ) coexist inside the Fe-NC/PMS system. The experiment results and degradation mechanism analysis revealed that N species(Pyridine N, Graphite N,Fe-N x ) and iron species (Fe0) were possible to be the active species of catalysts. Furthermore, Fe-NC/PMS system was investigated for possible pathway of TC degradation by liquid mass spectrometry (LC-MS), and the presence of intermediates was analyzed for toxicity magnitude by ECOSAR software.
研究领域:
环境科学
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催化材料
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Xiaohui Zhan,Junyan Liu,Yue Zhao,Yanping Sun,Rui Gao,He Wang,Huixiang Shi
In this study, we designed and synthesized Mn III with tunable spin state in g-C 3 N 4 through one-step calcination of Mn-MOF. The Mn atoms were induced into the six-fold cavity of the g-C 3 N 4 lattice and formed Mn-N 6 coordination. Mn-MOF served as the source of Mn. The collapse of Mn-MOF effectively promoted the stripping of stacked layers in g-C 3 N 4 and increased the atomic loading. The Mn-N coordination induced impurity energy levels which effectively regulated Mnx-CN's bandgap structure and accelerated the migration and separation of carriers. The O 2 − was activated to 1 O 2 by the energy released from the high-spin Mn III transferred ground state. The H 2 production of Mn 10 -CN (13479.19 µmol·g −1 ·h −1 ) is ∼32.2 times that of CN under visible light irradiation and with a remarkable apparent quantum yield (AQY) of 12.23% at 420 nm. The rates of TC degradation and Cr (VI) reduction achieved 0.059 and 0.18 min −1 , respectively. In addition, the practical application conditions and catalytic mechanism of Mnx-CN were explored. This work demonstrates the connection of the spin state of metal with the photocatalytic activity, providing an efficient photocatalytic system that can be used for solar-chemical energy conversion and pollution remediation, and presenting a new approach for modifying the g-C 3 N 4 -based catalysts.
研究领域:
材料科学
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光催化
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环境科学
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能源转换
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DOI
高影响因子
Advanced Energy and Sustainability Research
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2024
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IF 6.2
Hong Tu,Ying Xu,Shun-shun Chen,Ya Wang,Sheng-xin Guo,Jian Wu
The high catalytic activity of photocatalysts is greatly influenced by the efficient separation of photogenerated charge carriers. In this study, six g-C 3 N 4 -based COFs are designed and synthesized, and CN-203 is identified as the most efficient photocatalyst through experimental screening. Quantitative measurements reveal that singlet oxygen production is ≈100 times that of ·O 2 − and 5000 times that of ·OH. When combined with PMS, CN-203 exhibits degradation rates for RhB and TC that are ≈30 ( k = 0.0293 s −1 ) and 10 ( k = 0.2940 min −1 ) times faster than those of CN550(RhB, k = 0.0531 min −1 ; TC, k = 0.0301 min −1 ), respectively. Structural simulations and calculations show that the modified CN-203 have better electron–hole separation in the excited state, and the energy gap between HOMO and LUMO is significantly reduced after modification. The study also revealed the structure–function relationship between the modification of the same site with different functional groups and its effect on photocatalysis. Overall, this study provides valuable insights into the relationship between surface structure and photocatalytic applications.
研究领域:
材料科学
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化学
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Yuwen Chen,Ke Zhu,Wenlei Qin,Zhiwei Jiang,Zhuofeng Hu,Mika Sillanpää,Kai Yan
Spinel oxides are recognized as promising Fenton-like catalysts for the degradation of antibiotics. However, the catalytic performance is restrained by the poor electron transfer rate (ETR). Herein, hollow NiCo 2 O 4 @C nanocages are rationally designed and prepared to accelerate ETR in peroxymonosulfate (PMS) activation for tetracycline (TC) degradation. Enhanced ETR of the NiCo 2 O 4 @C/PMS system is due to three aspects: (1) The hollow nanocage facilitates the diffusion and adsorption of TC, improving the ion transfer at a macroscopic level; (2) Electron reconfiguration in octahedral sites of NiCo 2 O 4 increases the ratio of Co 2+ , resulting in highly efficient PMS activation; (3) In-situ generated carbon acts as “electron shuttles”, improving the electrical conductivity of catalysts at a microscopic level. As a result, the NiCo 2 O 4 @C demonstrates rapid ETR, leading to a high-efficiency activation of PMS. The NiCo 2 O 4 @C/PMS system exhibits exceptional TC degradation efficiency and reusability. Non-radical pathway, including 1 O 2 and direct electron transfer, dominates the system. This work offers a feasible strategy for enhancing electron transfer in the Fenton-like system.
研究领域:
环境科学
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材料科学
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催化
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水处理
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Tongtong Zhang,Yuqi Wang,Xin Xie,Yanning Shao,Yuhao Zeng,Siyu Zhang,Qishe Yan,Zhongjun Li
A dual Z-scheme carbon-bridged g-C 3 N 4 /BiOI-Bi 2 O 3 photocatalyst were synthesized by simple solvothermal and calcination methods. The physical and chemical properties of prepared samples were explored via a series of characterization and Density Functional Theory (DFT) calculations. The formation mechanism of the composite photocatalyst was systematically studied and the formation process was simulated. Under the irradiation of visible light, 10% carbon-bridged g-C 3 N 4 /BiOI-Bi 2 O 3 exhibited the best photocatalytic performance. And the kinetics reaction model was followed pseudo-first-order kinetics. Moreover, the possible TC degradation pathways were established based on LC-MS. The enhanced photocatalytic activity was mainly attributed to the dual Z-scheme heterojunction formed by carbon-bridged g-C 3 N 4 deposition on the surface of Bi 2 O 3 and BiOI and a higher charge transfer rate of carbon-bridged g-C 3 N 4 , which effectively promoted the separation and transfer of electron-hole pairs. The trapping experiments were carried out to further explore its photocatalytic mechanism. This work provided an in-depth understanding of g-C 3 N 4 and bismuth-based catalysts.
研究领域:
材料科学
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光催化
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环境科学
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化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Weixuan Guo,Sixiang Zhuang,Ying Peng,Yi Shen,Yungui Li,Suorong Zhang,Qile Fang
Designing high-performance heterostructure catalysts for peroxymonosulfate (PMS) activation is a promising research area. PMS-driven organic pollutant degradation via radical pathways usually suffers from the interference of other coexisting matters. In this study, we took a source design approach and employed a self-templating strategy using Prussian blue analog (PBA) precursors to fabricate CoFe/C heterostructure catalysts dominated by a nonradical pathway. Slow-speed coordination renders the CoFe PBA precursor with a highly ordered crystal structure and fewer coordinated water, resulting in an ideal carbon-encapsulated CoFe bimetallic catalyst (CoFe-S-T) with more high-valence metals and a graphitized carbon layer in its heterostructure; the obtained catalyst is proven to have superior catalytic performance for tetracycline (TC) degradation through a nonradical pathway in PMS-driven oxidation . The high Co III /Co II ratio and surface oxygen content make CoFe-S-T an excellent catalyst by boosting the generation of 1 O 2 , which is the predominant active species. In addition, CoFe-S-T has a high proportion of graphitized carbon layers, which significantly improves the direct electron transfer pathway. Thus, utilizing precursor design in a self-templating strategy is an effective method to synthesize high-performance heterostructures for PMS-driven organic pollutant degradation.
研究领域:
环境科学
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材料科学
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化学工程
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催化
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产品关联
DOI
高影响因子