RSC Advances
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2020
·Vol. 10
·期 3
·1757-1768
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IF 3.119
Yiqiu Liu,Yi Zhou,Qijun Tang,Qian Li,Si Chen,Zhuxing Sun,Haiqiang Wang
To explore an efficient photocatalyst for NO pollution, a direct Z-scheme photocatalytic system is successfully fabricated by coupling Bi2WO6 with NH2-UiO-66 via a simple hydrothermal synthesis technique. The Z-scheme system promotes the NO photocatalytic oxidation activity with an optimum NO removal rate of 79%, which is 2.7 and 1.2 times that obtained by using only pristine Bi2WO6 and NH2-UiO-66, respectively. Simultaneously, superior selectivity for converting NO to NO3−/NO2− is observed. The enhanced photocatalytic performance of the Bi2WO6/NH2-UiO-66 hybrids is attributed to the following two aspects: (i) large specific area of NH2-UiO-66, which exposes more active sites and is beneficial to the adsorption and activation of NO; (ii) outstanding Z-scheme structure constructed between BiWO6 and NH2-UiO-66, which can improve the efficiency of the separation of electron–hole pairs and preserves the strong oxidation ability of hybrids. ESR analysis shows that ·O2− and ·OH contribute to NO removal. A possible photocatalytic mechanism of NO oxidation on the direct Z-scheme photocatalyst (BWO/2NU) under visible light irradiation is proposed. This work displays the BWO/2NU hybrid's potential for treating low-concentration air pollutants, and the proposed Z-scheme photocatalyst design and promotion mechanism may inspire more rational synthesis of highly efficient photocatalysts for NO removal.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
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2014
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IF 1.342
Xiaodong WU,Haining YU,Duan WENG,Shuang LIU,Jun FAN
MnO and CeO 2 powders were mechanically mixed by a spatula and by milling to obtain loose-contact and tight-contact mixed oxides, respectively. The monoxides and their physical mixtures were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), Raman, O 2 temperature-programmed desorption (O 2 -TPD), H 2 temperature-programmed reduction (H 2 -TPR) and NO temperature-programmed oxidation (NO-TPO). The MnO x -CeO 2 solid solutions did not form without any calcination process. The oxidation state of manganese tended to increase while the ionic valence of cerium decreased in the mixed oxides, accompanied with the formation of oxygen vacancies. This long-ranged electronic interaction occured more significantly in the tight-contact mixture of MnO and CeO 2 . The formation of more Mn 4+ and oxygen vacancies promoted the catalytic oxidation of NO in an oxygen-rich atmosphere.
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2024
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IF 8
Yinghao Jia,Xin Hu,Hengjie Huang,Yangcan Deng,Wenning Cao,Ying Zhou,Xinghui Hou
CS- x ( x = 1, 2, 4, 6) nanoparticles have been successfully prepared by simple hydrothermal method combined with calcination process, and the calcination time is adjusted to optimize micro-structure characterization for their enhanced NO-sensing. The techniques of XRD, Raman, SEM, TEM, TGA, DSC, BET, and XPS are used to study their phase structure, micro-morphology, thermal decomposition process and surface states, then the possible gas-sensitive mechanism is analyzed. Results show that the typical CS-2 sensor has the maximum response of 130–50 ppm NO at 90 ℃, the short response/recovery time of 40/45 s, and the low detection limit of 0.1 ppm (1.18). It also has the reliable NO selectivity against to other interfering gases, good repeatability and high stability. Its enhanced NO-sensing performance may be due to the optimization of pore structure by adjusting the calcination process based on particles adhesion and mass transfer, which increases the pore size and specific surface area that could provide the channel and active sites for gas diffusion and adsorption, thus further promoting the gas-sensing reaction. The experimental methods and ideas of pore structure regulation provide a new way for the design of high-performance sensitive materials.
研究领域:
材料科学
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化学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Jiahe Zhai,Hui Wang,Abdelkader Labidi,Long Zeng,Yu Huang,Chuanyi Wang
Removing low-concentration NO in the air by means of photocatalytic technology is a promising approach. Herein, our work pins down the mechanism of cobalt metal doping within the lattice of Bi 4 Ti 3 O 12 (BTO) for the photocatalytic NO conversion. As a result, the Co-BTO exhibits a NO conversion efficiency of 58.3 %, which is substantially higher than that of BTO (30 %). More interestingly, the Co-BTO also shows a lower production of intermediate NO 2 than that of the BTO. These findings demonstrate that within Co-BTO, both Co²⁺ and Co³ ⁺ coexist. The redox cycle between these two cobalt species engenders active sites possessing strong reducing capabilities for O₂ which can be adsorbed and activated at the Co sites, thereby generating superoxide radicals (•O₂⁻). Furthermore, the doping of a certain portion of cobalt broadened light absorption and enhanced the separation efficiency of photogenerated carriers, further facilitating the activation of O₂. Lastly, electron spin resonance (ESR) and in-situ diffuse reflective infrared Fourier transform spectroscopy (in-situ DRIFTS) were respectively utilized to further clarify the active species involved in the photocatalytic oxidation of NO and its adsorption and conversion pathways from a mechanistic standpoint. Overall, this work represents a novel endeavor for the advancement of visible-light-driven photocatalysts usage for environmental remediation against NO pollution.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
Surfaces and Interfaces
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2021
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IF 4.837
Fan Wu,Chuan Pu,Minxian Zhang,Bin Liu,Jingling Yang
Solar photocatalysis is a clean and sustainable approach for removing atmospheric NO, but suffers from unsatisfactory removal efficiency. Efficient charge separation and surface reaction are critical factors ensuring the efficiency of solar energy conversion by photocatalysts. To achieve efficient charge steering and an enhanced surface reaction, we synthesized a bicomponent photocatalyst consisting of multivalent Ag species embedded in defect-rich twin-brush ZnO (Ag/TB-ZnO) with strong metal-support interaction (SMSI). The optimum Ag/TB-ZnO with silver loading of 2.0 wt.% achieved NO oxidation efficiency of 71.0% under a GHSV of 1,200,000 mL h −1 g −1 , and NO 3 − selectivity of 94.8%. Outstanding stability of up to 4 h was demonstrated. This superior performance was attributed to the enhanced efficacy of charge separation and surface reaction by the SMSI effect, surface plasmon resonance effect of metallic Ag and the efficient activation of oxygen species through vacancy-rich TB-ZnO.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
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2019
·Vol. 26
·期 36
·36933-36941
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IF 2.914
Chen Jun,He Jinjia,Wang Xiaoping,Hrynsphan Dzmitry,Wu Jiali,Chen Jianmeng,Yao Jiachao
Conversion of Fe II (EDTA)-NO or Fe III (EDTA) into Fe II (EDTA) is a key process in a wet flue gas denitrification technology with Fe II (EDTA) solution. In this work, the stoichiometry, kinetics, and thermodynamics of Fe II (EDTA)-NO reduction by Mn powder were investigated. We first studied the Fe II (EDTA)-NO reduction and product distribution to speculate a possible stoichiometry of Fe II (EDTA)-NO reduction by Mn powder. Then, the effects of major influencing factors, such as pH value, temperature, and Mn concentration, were studied. The pseudo-second-order model was established to describe the Fe II (EDTA)-NO reduction. Simultaneously, according to Arrhenius and Eyring-Polanyi equations, the reaction activation energy ( E a ), enthalpy of activation (∆ H ‡ ), and entropy of activation (∆ S ‡ ) were calculated as 23.68 kJ/mol, 21.148 kJ/mol, and − 149.728 J/(k mol), respectively. Additionally, simultaneous reduction of Fe III (EDTA) and Fe II (EDTA)-NO was investigated to better study the mechanism of Fe II (EDTA) regeneration, suggesting that there was a competition between the two reduction processes. Finally, a simple schematic mechanism of NO absorption by Fe II (EDTA) combined with regeneration of manganese ion and ammonium was proposed. These fundamental researches could offer a valuable guidance for wet flue gas denitrification technology with Fe II (EDTA) solution.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2015
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IF 4.097
Han Jin,Youju Huang,Jiawen Jian
Plate-like Cr 2 O 3 has been proved to be highly selective in sensing of nitric oxide (NO), while the sensing response of irregular shape and cubic-like Cr 2 O 3 toward NO was significantly interfered by hydrocarbons (HCs), e.g. C 3 H 6 . In this paper, sensing mechanism of the plate-like Cr 2 O 3 for selective sensing of NO (against HCs) was studied via crystallographic phase analysis, lattice fringes investigation and evaluation of the catalytic activity (gas-phase catalytic activity & electrochemical catalytic activity). The Cr 2 O 3 samples with plate-like, irregular shape and cubic-like microstructures have been confirmed to be the same crystallographic phase through XRD measurements, however, significant difference in the lattice fringes of these Cr 2 O 3 samples were observed via high-resolution transmission electron microscopy (HRTEM) & selected-area electron diffraction (SAED). The comparison results of catalytic activity for plate-like, irregular shape and cubic-like Cr 2 O 3 indicated that the unique selectivity for the plate-like Cr 2 O 3 was mainly caused by the electrochemical reaction specifically toward NO, which occurred near the interface between plate-like Cr 2 O 3 and zirconia-based electrolyte.
研究领域:
材料科学
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化学工程
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传感技术
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DOI
高影响因子
ENERGY & FUELS
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2022
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IF 4.654
Wei Zhang,Jie Zhao,Ahmed A. Allam,Yue Xin,Jingqi Lin,Ting Gao,Jamaan S. Ajarem,Ximing Li,Chuanyi Wang,Detlef W. Bahnemann
Bi2WO6 is a promising photocatalyst for NOx removal, owing to its wide solar light absorption and specific photoelectric properties. Nevertheless, enhancing its efficiency remains a major concern. Palladium proves to be a good co-catalyst for semiconductor materials, but how the combination of Pd and bismuth tungstate affects the efficiency of NO removal and relevant process is still vague. In this work, nutshell-like bismuth tungstate was synthesized using a hydrothermal method, followed by photo-depositing Pd nanoparticles with different contents. The obtained photocatalysts were characterized by X-ray diffraction, specific surface area analyzer (BET), X-ray photoelectron spectroscopy, and scanning electron microscopy. Among the prepared photocatalysts, Bi2WO6 deposited with 1 wt % Pd shows the best photocatalytic activity with a NO removal efficiency of 58%, which is 2.9 times that of the Bi2WO6 under the same conditions. The enhanced photocatalytic activities were attributed to the comprehensive effects of the high efficiency in separating electrons and holes, improvement in invisible light utilization and BET specific surface areas of Pd–Bi2WO6 nanocomposites. More importantly, it was found that NO2 is the main product over Bi2WO6, whereas the conversion of NO to NO3– (an environmentally friendly product) is dominant over Pd-modified Bi2WO6 due to the enhanced separation of electrons and holes. Active species capture experiments show that photo-generated holes (h+) and •O2– play an important role in NO removal. The present work provides new insights into the role of Pd cocatalysts in NO removal.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
Catalysts
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2019
·Vol. 9
·期 6
·519
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IF 3.444
Jiaming Shao,Fawei Lin,Yan Li,Hairong Tang,Zhihua Wang,Peixi Liu,Guanyi Chen
NO oxidation was conducted over MnOx-CeO2catalysts, which were synthesized by the co-precipitation method. The calcination temperature and third metal doping were the main considerations. MnCe catalysts calcined at 350 °C and 450 °C attained the highest NO conversion efficiency, compared to 550 °C. XRD results suggested that the higher the calcination temperature, the higher the crystallization degree, which led to a negative effect on catalytic activity. Subsequently, Sn, Fe, Co, Cr, and Cu were separately doped into MnCe composites, but no improvement was observed for these trimetallic catalysts in NO conversion. Nevertheless, MnCeSn, MnCeFe, and MnCeCo still exhibited a desirable NO conversion efficiency, so they were tested under SO2addition together with MnCe catalyst. Among them, MnCeFe exhibited the highest NO conversion after whole poisoning testing. XPS results indicated that Fe could protect Mn and Ce metal oxides from being reduced during SO2poisoning process. Furthermore, in in-situ DRIFTS measurement, part of nitrate species maintained undestroyed on the MnCeFe catalyst surface after SO2poisoning. These characteristics reinforced that Fe dropping would achieve better performance under SO2atmosphere.Keywords:MnOx-CeO2;co-precipitation;NO oxidation;SO2resistance;metal addition
研究领域:
环境科学
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催化化学
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DOI
高影响因子
Journal of Water Process Engineering
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2024
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IF 6.3
Jing Li,Suxia Ma,Nuo Xu
The pursuit of carbon peaking and carbon neutrality goals necessitates flexible operation and deep peaking of coal-fired units, thus placing heightened demands on nitrogen oxide (NO X ) emission control. Fly ash, a solid waste rich in silicon (Si) and aluminum (Al), should be fully leveraged, and the high-value synthesis of zeolite represents a viable utilization method. In this context, fly ash-based zeolite was prepared as a catalyst to facilitate the generation of active oxides from H 2 O 2 , combined with alkali solution absorption, to achieve efficient denitrification. This approach effectively transforms ‘waste to pollution’ mitigation. The optimal synthesis conditions for FA-ZSM-5 zeolite were established using the alkali fusion hydrothermal synthesis method, with fly ash as the raw material. The specified conditions were NaOH/FA = 1.2, SiO 2 /Al 2 O 3 = 40, H 2 O/Al 2 O 3 = 1325, TPAOH/Al 2 O 3 = 10, ZSM-5-seed addition of 5 %, and a hydrothermal temperature and time of 140 °C for 24 h. Experimental parameters were meticulously investigated to ascertain their impact on nitric oxide (NO) removal efficiency. The highest removal efficiency was achieved under specific conditions: a reaction temperature of 140 °C, an H 2 O 2 concentration of 6 %, a catalyst dose of 0.3 g, an NO concentration of 600 mg/m 3 , and an SO 2 concentration of 1000 mg/m 3 . Finally, analysis of the catalytic oxidation mechanism revealed that H 2 O 2 , when catalyzed by FA-ZSM-5 zeolite, generates ·OH radicals with strong oxidizing properties, thereby facilitating the oxidative removal of NO.
研究领域:
环境科学
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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
Journal of Environmental Chemical Engineering
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2024
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IF 7.4
Dong Wang,Xiao Zhang,Wenbin Shi,Ping Yang
Expanding light response is a significant approach to increase the harvesting efficiency of solar energy for photocatalysts. In this paper, aqueous CsPbBr 3 nanocrystals (NCs) were created using sol-gel glass as a reactor. These bright SiO 2 glass-coated NCs were decorated on hollow TiO 2 bowl array (TBN) via mechano-chemical pre-reaction and subsequent hydrothermal treatment for the first time to enhance the photocatalytic performance for NO removal. The homogeneous distribution of the NCs and the well-developed interface in type II CsPbBr 3 /TiO 2 heterostructures play important roles for improving the separation and transfer of photogenerated charge carriers. The light response of the CsPbBr 3 NCs increased the harvesting efficiency of solar energy. In addition, the bright photoluminescence of the CsPbBr 3 NCs was almost quenched to further confirm the separation of the photogenerated charge carriers in the heterostructures. Using optimized preparation conditions, the CsPbBr 3 /TiO 2 composite sample revealed an outstanding NO removal rate of 77.9 % at a concentration of 300 ppb, in which 45.2 % of NO was removed using pure TBN. In addition, the CsPbBr 3 /TiO 2 sample revealed excellent performance for photocatalytic H 2 O 2 evolution rate of 104.3 µM∙L −1 ∙h −1 , suggesting the CsPbBr 3 /TiO 2 composite can be applied for various photocatalytic fields. These results supplied new insights for the synthesis of photocatalysts and application of perovskite NCs.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
ChemCatChem
·
2025
·
IF 3.9
Yingshan Xue,Ping Wang,Cheng Yang,Jiasai Yao,Tianbao Zhang,Xin Zhang,Jing Xiong,Xiaohua Sun,Yuechang Wei,Zhenxing Li
Nitrogen oxides are an industrial and domestic waste gas, which pollutes the air and affects health. In this paper, we use the template method to achieve the doping of alkaline earth metals, and the alkaline earth metals are doped into cerium-manganese-based three-dimensional ordered macroporous (3DOM) catalysts to detect NO oxidation. The introduction of alkaline earth metals can improve the stability and thickness of macroporous results, which increases the contact area between the catalyst and reactant gases. At the same time, alkaline earth metal doping can promote the formation of more oxygen vacancies and unsaturated structures, and improve the catalytic activity of NO oxidation. The NO conversion rate of CM-3Mg doped with 3% Mg was 61.25% at 250°C, and the NO conversion rate was the highest at 303°C, which was 79.2%. This study provides a promising catalyst candidate for NO oxidation in practical applications.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
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