APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Xiaoqi Zhao,Yingxiao Li,Xue Zhang,Yanfang Gao,Ling Liu
Surface oxygen vacancy increases active site numbers, and multidimensional cross-linked structure improves the exposure of active sites. Thereby, they can enhance the oxygen reduction reaction (ORR) performance of Fe-N-C catalysts effectively. Herein, Fe(NO 3 ) 3 ·9H 2 O and carbon nanotubes (CNTs) were introduced into zeolitic imidazolate framework nano leaves (ZIF-L) to prepare multidimensional cross-linked Fe-N-CNTs with surface oxygen vacancies through co-pyrolysis at the high-temperature. As expected, the synthesized multidimensional cross-linked Fe-N-CNTs-900-0.2 composite rich in oxygen vacancies increased the conduction band potential and improved the reducing capacity. Thus, Fe-N-CNTs-900-0.2 possessed a better ORR electrochemical performance (half-wave potential = 0.892 V vs. RHE) that surpass the Pt/C catalysts. Moreover, the Al-air batteries containing Fe-N-CNTs-900-0.2 displayed a higher maximum power density than those of Pt/C catalysts. The electronic band structure shows that Fe-N-CNTs-900-0.2 rich in oxygen vacancy concentration has higher conduction band potential and effectively improves the activity of ORR catalysts. This work innovatively proposes that the joint work of multidimensional cross-linked structure and oxygen defects is an effective method to enhance the ORR performance and clarifies its internal reaction mechanism, which provides a new idea to design and preparer Fe-N-C catalysts.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
JOURNAL OF CHROMATOGRAPHY A
·
2017
·
IF 3.981
Sha Chen,Xiao-Xin Li,Lun Shu,P. Somsundaran,Jian-Rong Li
The baseline separation of divinylbenzene (DVB) and ethylvinylbenzene (EVB) isomers was achieved using HPLC with MIL-53(Fe) and MIL-100(Fe) packed columns respectively when hexane/dichloromethane (100:0) used as mobile phase, at flow rate of 0.5 mL min −1 , room temperature, and monitored with a UV detector at 254 nm. The two Fe-based MILs packed columns showed different separated performances, analytes had short retention time on MIL-100(Fe) compared to MIL-53(Fe), but selectivity of DVB isomers (m-DVB and p-DVB) was lower, which was mainly due to the differences of the pore size and structure of MILs. Moreover, the results of calculated thermodynamic parameters showed that the separation of DVB and EVB isomers was not only controlled by enthalpy change (ΔH), but also controlled by entropy change (ΔS). The head-to-tail stacking was the main reason for the separation according to the mechanism of the DVB and EVB isomers on Fe-based MILs packed columns.
研究领域:
分析化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
ANALYTICAL CHEMISTRY
·
2025
·
IF 6.7
Chengzhuo Yu,Jin Xu,Li Xiong,Yarui Wang,Silong Wang,Fanglan Geng,Zesen Shang,Huasheng Wu,Lixia Zhao,Yawei Wang
Luminol-based chemiluminescence (CL) systems, as a powerful tool for bioanalysis, are limited owing to their weak CL intensity and self-decomposition of the classic oxidant H2O2. Herein, we introduced a new luminol CL enhancer, the natural light-driven photocatalyst MIL-100(Fe)/TiO2, for the selective determination of dopamine (DA). By employing MIL-100(Fe)/TiO2 for the first time as an efficient enhancer, the MIL-100(Fe)/TiO2-luminol CL intensity was 100 times higher than that of the classical H2O2-luminol system. The CL spectrum, UV–vis absorption spectroscopy, radical scavenger experiments, and electron spin resonance spectroscopy were utilized to investigate the possible CL mechanism of the MIL-100(Fe)/TiO2-luminol system. All of the results indicated that MIL-100(Fe)/TiO2 can generate reactive oxygen species under mild natural light, which could react rapidly with the luminol anion radical and result in direct CL emission. The sensitive plate for DA was developed based on its inhibiting effect on CL intensity, and the linear range between CL intensity and DA concentration was 100 nM–1000 μM with a detection limit of 16.7 μM (S/N = 3). This study successfully achieved a stable reactant that can directly trigger the CL of luminol without the need for additional oxidizing agents under mild natural light and offers new possibilities for photoinduced amplification technology.
研究领域:
分析化学
·
生物医学工程
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DOI
PubMed
高影响因子
Molecular Catalysis
·
2021
·
IF 5.062
Yu Guan,Yinhe Liu,Qiang Lv,Bo Wang
The selective catalytic reduction of nitrogen oxides (NO x ) by carbon monoxide (CO-SCR) is a promising way to deal with exhaust gasses. And Effective redox cycle and NO dissociation ability are crucial factors for catalytic reduction of NO x . Herein, Fe decorated CeO 2 microsphere catalysts with surface oxygen defect were synthesized by solvothermal and calcination method. Among all catalysts, 0.5Fe-CeO 2 sample showed excellent catalytic performance with efficiency near 96% for NO reduction under the condition of 550 ppmv NO, 1200 ppmv CO, and 40,000 h − 1 of GHSV. It was found that Fe doping could efficiently regulate Ce 4+ /Ce 3+ redox couple and oxygen vacancy for catalytic activity. XRD, Raman, XPS, EPR and H 2 -TPR etc. were employed to explore the physicochemical properties of samples. The results showed that Fe had been incorporated into CeO 2 by XRD, and the results of Raman spectrum and XPS indicated that Ce 4+ /Ce 3+ redox couple existed in 0.5Fe-CeO 2 catalyst. Furthermore, the H 2 -TPR spectrum displayed the formation of oxygen vacancy in the samples. N 2 adsorption-desorption isotherms indicated that the doping of Fe could enlarge the specific surface area, pore volume and pore dimeter of the samples, and thus greatly enhanced the NO adsorption and further NO catalytic reduction on catalysts. In addition, other characterization of physicochemical properties and density functional theory (DFT) calculation were performed to reveal the mechanism of NO + CO reaction. As a result, a mechanism was proposed to elucidate highly efficient NO reduction over the catalysts of Fe decorated CeO 2 microspheres. Finally, the synergistic effects of redox center and oxygen vacancy on catalytic activity enhancement were revealed. This work provides a promising way to the design of efficient catalysts for NO reduction.
研究领域:
催化化学
·
环境科学
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DOI
高影响因子
ChemSusChem
·
2022
·Vol. 15
·期 16
·e202200741
·
IF 9.14
Ziyuan Xiu,Ming Zheng,Jiadong Li,Feng Wei,Changchang Dong,Mingrui Zhang,Xin Zhou,Xiaojun Han
Graphical Nitrogen reduction : A bionic nitrogen fixation system composed of Fe-VS 2 nanosheets and 1-aminoanthraquinone-functionalized polymethacrylic acid (1-AAQ-PA) matrix is fabricated with 1-AAQ-PA as the electron medium to achieved high NH 3 yield rate of 31.6 μg h −1 mg −1 and faradaic efficiency to NH 3 of 23.1 % in 0.05 m Li 2 SO 4 electrolyte at −0.35 V vs. reversible hydrogen electrode. This work provides inspiration and insights for the development of effective catalyst systems for nitrogen reduction. Electrochemical N 2 fixation is considered to be a promising alternative to Haber–Bosch technology. Inspired by the composition and structure of natural nitrogenase, Fe-doped VS 2 nanosheets were prepared via one-step solvothermal method. The electron transfer system mediated by organic conductive polymer (1-AAQ-PA) was constructed to promote the electron transfer between Fe-VS 2 nanosheets and the electrode in electrocatalytic N 2 reduction reaction (NRR). The obtained 1-AAQ-PA−Fe-VS 2 electrode converted N 2 to NH 3 with a yield of 31.6 μg h −1 mg −1 at −0.35 V vs. reversible hydrogen electrode and high faradaic efficiency of 23.5 %. The introduction of Fe dopants favored N 2 adsorption and activation, while the Li−S bond between Fe-VS 2 and Li 2 SO 4 effectively inhibited hydrogen evolution. The highly efficient electron utilization in the electrocatalytic NRR process was realized using the 1-AAQ-PA as the electron transfer medium. Density functional theory calculations showed that N 2 was preferentially adsorbed on Fe and reduced to NH 3 via both distal and alternating mechanism.
研究领域:
电化学
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材料科学
·
催化反应
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DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Xiaodong Chen,Ning Wang,Kui Shen,Yangkai Xie,Yongpeng Tan,Yingwei Li
In order to improve the catalytic performance of oxygen reduction reaction (ORR), it is pivotal to increase the density and accessibility of the active sites. Herein, we have developed a template-free melamine-assisted cocalcined strategy to afford Fe-embedded and N-doped carbons (Fe–N–C) with not only high density of atomically dispersed Fe–Nx active sites but also abundant three-dimensional interconnected mesopores by directly pyrolyzing Fe-ZIF-8 covered with a controllable melamine layer. It is demonstrated that the introduction of melamine in the precursor plays a key role in constructing various carbonized products with controllable morphology, porosity, and components. With an optimal mass ratio 1:1 of melamine to Fe-ZIF-8, the resultant Fe@MNC-1 exhibits excellent ORR activity and stability, which exceeds 20 wt % commercial Pt/C catalyst (with a half-wave potential of 0.88 V vs 0.85 V) in an alkaline electrolyte and is even comparable to the commercial Pt/C catalyst (with a half-wave potential of 0.78 V vs 0.80 V) in an acidic electrolyte. To the best of our knowledge, Fe@MNC-1 can be ranked among the best nonprecious metal electrocatalysts for ORR in both alkaline and acidic media. The present synthetic strategy may provide a new opportunity for the design and construction of metal–organic framework-derived nanomaterials with rational composition and a desired porous structure to boost their electrocatalytic performance.
研究领域:
材料科学
·
电化学
·
催化
·
纳米材料
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DOI
PubMed
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 65
·40952-40956
·
IF 3.108
Chunlin Tan,Xiuya Su,Chao Zhou,Baoju Wang,Qiuqiang Zhan,Sailing He
Red-emitting carbon dots (C-dots) were synthesized from p-phenylenediamine (p-PD) aqueous solution with nitric acid (HNO3) assistance by hydrothermal reaction at 200 °C for 2 h. p-PD aqueous solution can be transferred to C-dots (or poly(p-PD)) with (or without) the addition of acid. Different acid systems, such as HNO3, H3PO4 and HF, can directly synthesize red-emitting C-dots, and the fluorescence can be enhanced by increasing the strength of acids. N-CDs, 3.46 nm-average-sized C-dots, prepared in dilute HNO3, have a quantum yield of 15.8% with unique, excitation-wavelength independent emission in the red region (600 and 680 nm) and a broad visible excitation band. Carboxyl, ester and hydroxyl groups on the C-dots surface directly lead to red emission. N-CDs have a certain selective specificity for Fe3+ detection and the linear range is 10–300 nmol L−1 with a limit of determination of 1.9 nmol L−1.
研究领域:
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Yixuan Liu,Jiamin Wei,Qi Zong,Chaoyue Chen,Tinghai Yang,Weiqiao Liu
Constructing cost-efficient and robust Fe-MIL-based photocatalysts for efficiently photodegrading antibiotics is highly appealing, however, their intrinsic defects, particularly unsatisfied visible light harvesting efficiency and rapid recombination of charge carriers, provide significant challenges. Herein, oxygen-vacancy-rich Bi 2 WO 6 -OVs/NH 2 -MIL-88B (Fe) composites were successfully constructed via a two-step approach consisting of a hydrothermal reaction followed by NaBH 4 treatment. The chemical compositions, microstructure, morphology, as well as optical properties of the as-prepared samples were thoroughly established. The optimized Bi 2 WO 6 -OV(40)/NH 2 -MIL-88B(Fe) photocatalyst exhibited the maximum photocatalytic efficiency (95.3 %) for the photodegradation of Norfloxacin (NOR), which was considerably greater than that of the heterostructure (56.9 %). The enhancement of photocatalytic performance can be attributed to the collaborative effect between oxygen vacancies and hybrid heterojunctions, which jointly enhances photoexcited electron generation and accelerates charge transfer. Furthermore, from the perspective of practical applications, the effects of pH, NOR concentration, and photocatalyst reuse were carefully investigated. The radical trapping experiments and ESR results verified that superoxide radicals (•O 2 − ), holes (h + ), and hydroxyl radicals (•OH) were the main active species in the NOR degradation process, and the possible photocatalytic mechanism was speculated accordingly. This research provides a promising approach to fabricating Fe-MOF-based heterojunctions with surface oxygen vacancy defect modification for the photodegradation of antibiotics.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
CATALYSIS COMMUNICATIONS
·
2017
·
IF 3.33
Bo Xu,Zhiming Chen,Bing Han,Cuncheng Li
This work presents MIL-100(Fe) nanoparticles synthesized using glycol with uniform size and morphology. This is the first report of nanoscale MOFs material synthesized using glycol. The MIL-100(Fe) particles have been characterized by SEM, TEM, XRD and the results indicate that the MOFs particles show monodispersed nanospherical morphology. Photocatalytic study reveals that the MIL-100(Fe) nanospheres exhibit good oxidation ability of benzene to phenol under visible light irradiation with high selectivity.
研究领域:
材料科学
·
环境科学
·
化学工程
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产品关联
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2023
·
IF 7.8
Zibin Pan,Qingqiang Gao,Zuliang Chen
The elimination of arsenic (As) from arsenic-contaminated mine groundwater has become a worldwide problem because it causes environmental degradation and poses serious risks to human health. In this study, biosynthesized Fe/Cu nanoparticles (Fe/Cu NPs) were used for the simultaneous elimination of As(Ⅲ) and As(Ⅴ) from aqueous solution, resulting in their maximum amounts removed at 8.5 and 17.5 mg/g, respectively. SEM, FTIR, and XPS characterizations indicate that the Fe component on the Fe/Cu NPs acted as an adsorption and catalyst, while the Cu component mainly developed into a co-precipitation reaction with the As species, also facilitating the Fe catalytic processed. Meanwhile, adsorption isotherms , kinetics, and DFT calculations reveal that the removal of As(Ⅲ) was primarily physical/chemical adsorption and oxidation , while the elimination of As(Ⅴ) was co-precipitation and chemisorption. The most stable adsorption site, receiving 0.252 and 0.306 electrons from As(Ⅲ) and As(Ⅴ), respectively, was the unsaturated complexes of iron on the Fe/Cu NPs. Finally, the measurements and XPS results of Fe/Cu NPs in the treatment of groundwater show that the reduced capacity to remove As was attributed to a complex reaction system that disrupted the function of the Cu component, including co-precipitation and made the catalytic process possible. This explains there are differences in the reaction processes of biosynthetic Cu/Fe NPs in aqueous solution and groundwater.
研究领域:
环境科学
·
纳米技术
·
水处理
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DOI
高影响因子
Analytical Methods
·
2014
·Vol. 6
·期 19
·7973-7977
·
IF 1.938
Yingfeng Qin,Liangliang Zhang,Gaojie Ye,Shulin Zhao
A homogeneous label-free colorimetric sensing strategy for bleomycin (BLM) assay was developed on the basis of BLM enhanced Fe(II)–H2O2–ABTS reaction. Fe(II) exhibits a catalytic effect on H2O2-mediated oxidation of ABTS by Fenton chemistry. BLM·Fe(II) complex possessed a significantly higher catalytic ability than Fe(II) probably because of the further formation of more active “activated oxo-iron-bleomycin complex”. The present method was convenient without any complicated chemical synthesis, modification, or tedious experimental procedures. Analysis results can be seen with the naked eye and monitored by UV-vis spectra. The peak absorbance exhibits a linear relationship with BLM concentrations from 25 nM to 1 μM, and a detection limit of 16 nM can be achieved. The designed colorimetric strategy may provide a promising alternative for BLM detection in clinical samples.
研究领域:
分析化学
·
生物医学
·
临床检验
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产品关联
DOI
高影响因子
DIAMOND AND RELATED MATERIALS
·
2025
·
IF 5.1
Miaomiao Chen,Meng Zhou,Caihong Mao,Chunchao Wu,Shujie Pang,Xudong Yang
Fluorescent hydrogel were developed for Fe(II) detection to overcome the shortcomings of simple carbon dots solutions (CDs), which are difficult to store and use. CDs were prepared using the hydrothermal synthesis with o -phenylenediamine and dopamine as the carbon sources. Fluorescent hydrogel (CACDs) were obtained by doping CDs in and impregnating them with carboxymethyl cellulose hydrogel (CA) prepared using crosslinked carboxymethyl cellulose (CMC), which was grafted using acrylamide as the substrate. Using CDs and CA as a fluorescent group and a backbone, respectively, enhanced the fluorescence performance and facilitated Fe(II) detection. The surface groups, elemental composition and optical properties of the prepared CDs and CACDs were systematically studied using FTIR, XRD, UV–Vis and fluorescence spectrometer. The effects of pH, temperature, NaCl salt solution and UV irradiation on the stability of CDs in the hydrogel were discussed. CACDs exhibited strong, bright yellow fluorescence with a fluorescence intensity 4.35 times higher than that of CDs. CACDs can be used as fluorescent probes to realise real-time detection of Fe(II) at a low detection limit (0.22 μM), allowing them to be employed for Fe(II) detection in real water samples. CACDs had stable adsorption properties for Fe(II). The adsorption process of metal ions conformed to pseudo-second order kinetics and Langmuir model, respectively. Therefore, CACDs are expected to be bifunctional materials for effective detection and removal of Fe(II).
研究领域:
材料科学
·
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
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