JOURNAL OF THE ENERGY INSTITUTE
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2022
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IF 6.47
Longyi Xue,Ninghan Wei,Cheng Zhao,Xiaomei Hu,Junge Yun,Zimo Chen,Zhiyi Deng,Zhihang Chen
CeO 2 as selective catalytic reduction (SCR) catalyst has attracted wide attention due to its abundant surface acidity and excellent oxygen storage/release capacity. However, its further implication was hindered owing to insufficient catalytic activity and SO 2 resistance. Novel Cr doped CeO x catalysts were synthesized by solid phase method and used for NH 3 -SCR of NO x at middle-low temperature. The effect of Cr addition on the SCR performance and physicochemical properties of CeO 2 catalyst was investigated by activity test and characterizations. Among the tested catalysts, Cr(0.4)-CeO x catalyst exhibited excellent NO x removal efficiency, with >90% NO conversion within 180–300 °C, 100% NO conversion at 220 °C and outstanding SO 2 resistance at 240 °C under 100 or 600 ppm SO 2 . The characterizations results revealed that Cr modified CrCeO x catalyst could effectively increase BET surface area, pore volume, surface acidity and redox capacity. In situ DRIFTS indicated that SCR reactions over Cr(0.4)-CeO x catalyst followed Eley-Rideal mechanism and active –NH 2 was the major intermediate species. After sulfuration, Cr(0.4)-CeO x still exhibited excellent SCR activity due to the increase of Cr 6+ , Ce 3+ and O α concentration and the formation of Cr–O–Ce bond, new Brønsted acid site and more crystallized Cr 2 O 3 .
研究领域:
催化化学
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环境科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2021
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IF 3.764
Wuyuan Liu,Zihan Gao,Xiangyun Zhao,Jiajian Gao,Runnong Yang,Lin Yu
The Cr-doped CeO2–TiO2 catalysts (CrCeTi) were produced via a coprecipitation method and used for selective catalytic reduction (SCR). The CrCeTi catalyst has good catalytic performance and sulfur resistance. The results of X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), NH3-TPD, NO-TPD, X-ray photoelectron spectroscopy (XPS), and H2 temperature-programmed reduction (H2-TPR) suggested that the CrCeTi catalyst with high specific surface area (SSA), strong surface acidity, enhanced redox properties, and effective electron transfer (3Ce4+ + Cr3+ ↔ 3Ce3+ + Cr6+) were the important promotion factors for excellent SCR properties. The in situ diffuse reflectance infrared spectroscopy (DRIFTS) indicated that the incorporation of Cr could improve the adsorption capacity of nitrate and the activation capacity of NH3, which were conducive to enhancing the catalytic activity. The thermogravimetric analysis-mass spectrometry (TG-MS) confirmed that the doping of Cr reduced SO2 surface adsorption and promoted the decomposition of NH4HSO4 (ABS). Therefore, the CrCeTi catalyst showed excellent resistance to SO2 poisoning.
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
CATALYSIS LETTERS
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2021
·Vol. 151
·期 8
·2250-2256
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IF 3.186
Liu Qi,Wang Shihao,Xu Gang,Wu Minghong,Chen Jianjun,Li Junhua
Abstract A novel TiO 2 -supported vanadium-substituted tungstophosphoric acid (PW 11 V/TiO 2 ) catalyst was designed and applied for selective catalytic reduction of NO x by NH 3 . Compared with the commercial tungstophosphoric acid (PW 12 /TiO 2 ), PW 11 V/TiO 2 displayed a nearly 90% activity improvement at 300 °C. In addition, the favorable resistance and stability to SO 2 were also obtained over PW 11 V/TiO 2 catalyst. Phase analysis and spectroscopy results indicated the vanadium was successfully incorporated into the molecular structure of PW 12 , and the Keggin framework still keep stable over the TiO 2 support. H 2 -TPR test proved the incorporation of vanadium promoted the redox ability of PW 11 V. The present study provides us an effective way to improve the performance of catalytic removal of NO x through tungstophosphoric acid catalyst. Graphic Abstract
After introduction of V species, the obtained PW 11 V/TiO 2 catalyst show better NH 3 -SCR performance and N 2 selectivity than PW 12 /TiO 2 catalyst.
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 ELECTRONIC MATERIALS
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2021
·Vol. 50
·期 11
·6414-6425
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IF 1.938
Fan Wentao,Du Yongqiang,Zhou Jianjun,Ma Xueqing,Liu Yingliang,Xu Shengang,Cao Shaokui
The introduction of polymer additives provides a simple effective method to modify perovskite grain boundaries to improve power conversion efficiency (PCE) and stability of perovskite solar cells (PSCs). In this work, the high-quality methylammonium lead triiodide (MAPbI 3 ) perovskite film is prepared by adding the protonated polyamide-amine dendrimer (NH 3 + -PAMAM) to the perovskite precursor solution to regulate the crystalline growth process. The cross-linked perovskite grain structure induced by dendritic NH 3 + -functionalized PAMAM macromolecules results in the formation of compact and pinhole-free perovskite film owing to the suppression of perovskite gain boundaries. Finally, the unsealed NH 3 + -PAMAM modified PSC device achieves the highest PCE value of 16.03%, representing an increase of 48% compared with the control PSC device. Also, the unencapsulated NH 3 + -PAMAM-modified PSC device retained 75% of initial PCE value after being exposed to an ambient environment for 20 days, which is obviously higher than 10% for the control device. The improvements of perovskite morphology and photovoltaic performance are attributed to the modification of NH 3 + -PAMAM dendrimers. Graphic abstract
研究领域:
材料科学
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能源科学
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DOI
高影响因子
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2013
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IF 2.145
Rui-tang Guo,Yue Zhou,Wei-guo Pan,Jie-nan Hong,Wen-long Zhen,Qiang Jin,Cheng-gang Ding,Shi-yi Guo
CeO 2 /Al 2 O 3 catalysts prepared by three methods were investigated for selective reduction of NO with NH 3 . It was found that the catalyst prepared by the single step sol–gel method had the best SCR activity and SO 2 resistance performance. From the results of BET, XRD, TPD and TPR, it can be concluded that large surface area, strong interaction, highly dispersed nano-crystalline ceria , high NH 3 adsorption capacity and good redox ability might be the main reasons for the excellent performance of CeO 2 /Al 2 O 3 catalyst prepared by the single step sol–gel method.
研究领域:
催化
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环境科学
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材料科学
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DOI
高影响因子
Journal of Materials Chemistry A
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2018
·Vol. 6
·期 18
·8705-8711
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IF 9.931
Hao Xu,Qinming Wu,Yueying Chu,Jingang Jiang,Ling Zhang,Shuxiang Pan,Changsheng Zhang,Longfeng Zhu,Feng Deng,Xiangju Meng,Stefan Maurer,Robert McGuire,Andrei-Nicolae Parvulescu,Ulrich Müller,Feng-Shou Xiao
2,6-methyl-N-methylpyridinium, as a novel organic template, is employed for the synthesis of RTH aluminosilicate zeolite with a SiO2/Al2O3 ratio of 17.6. The amount of 2,6-methyl-N-methylpyridinium template, the Na2O/SiO2 ratio, the SiO2/Al2O3 ratio, and the H2O/SiO2 ratio in the starting gel significantly influence the crystallization of RTH zeolite. Several analytical methods such as XRD, SEM, N2 sorption, TG-DTA, DRIFT and NMR were employed for the characterisation of the obtained RTH zeolites and to understand the crystallization process with the new template. Very interestingly, the crystallization of RTH zeolite with the new template takes a very short time (12 h at 130 °C and 50 min at 240 °C) compared with conventional RTH zeolite synthesis reported in the literature (72 h at 130 °C). Theoretical calculations show that this novel organic template has lower interaction energies for zeolite cage space filling than those of the organic templates previously reported in the literature, which lead to stronger structural directing. Kinetic results show that the activation energy of this novel organic template is much lower than that of the traditional one. Catalytic tests show that copper exchanged RTH zeolite (Cu-RTH) exhibits good catalytic properties in the NH3-SCR reaction and the H-RTH zeolite catalyst has excellent selectivities for ethylene and propylene in MTO reactions.
研究领域:
催化材料
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化学工程
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环境科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
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IF 5.8
Qiaowen Zheng,Yanmei Zhou,Jiarong Huang,Heng Lu,Shaoru Wu,Junying Zhang,Yishan Li,Wenping Hong,Xiaohong Tan,Jinming Lin,Qiang Chen,Feiming Li,Zhixiong Cai,Maosheng Zhang
Cu-based perovskite nanocrystals (NCs) have received great interest as alternatives to lead-based perovskite NCs due to their unique advantages of resource abundance and being environmentally friendly. However, the issue of their inherent low luminous efficiency has limited the application of fluorescence sensing fields. In this work, a highly sensitive fluorescence sensor based on Cu-based perovskite NCs has been constructed by embedding Cs 3 Cu 2 I 5 NCs in room temperature curable deep eutectic solvents (Cs 3 Cu 2 I 5 -DES) for the detection of NH 3 gas in the atmosphere. In this strategy, Lauric acid-based DES with room temperature curable property were successfully synthesized and used as the supporting materials of Cs 3 Cu 2 I 5 -DES sensing film. When NH 3 gas exists, NH 3 can be adsorbed and enriched on the surface of Cs 3 Cu 2 I 5 -DES film, and react with the carboxyl group on the DES, which leads to a significant decrease in the fluorescence intensity of Cs 3 Cu 2 I 5 -DES film. Under optimized experimental conditions, the as-prepared sensing film demonstrated a good linear relationship between the decreased intensity of the fluorescence and the NH 3 concentration, and a low limit-of-detection (LOD) of 0.0642 ppm for NH 3 . Furthermore, the sensor also exhibited excellent selectivity and good stability.
研究领域:
材料科学
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环境科学
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化学传感器
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DOI
高影响因子
Catalysis Science & Technology
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2023
·Vol. 13
·期 10
·3147-3157
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IF 5
Hange Wang,Wen Chen,Wei Jin,Yueli Liu
SCR technology is considered to be the most effective method for denitrification. However, the low NOx conversion rate of the current catalysts at low temperatures limits their further application. Herein, Sn-doped modified CoAl-LDH carriers are synthesized by a hydrothermal method, and the typical hexagonal sheet structure of the MnOx(0.25)/CoSn3Al-LDO catalyst achieves 100% NO conversion at a wide range of 120–330 °C with a GHSV of 30 000 h−1, and the 100% NO conversion may be maintained at 200 °C for 30 h. After the introduction of 150 ppm SO2 at 200 °C, the NO conversion of the MnOx(0.25)/CoSn3Al-LDO catalyst is maintained at 73.4%, which is greatly improved compared with those of CoAl-LDO and MnOx(0.25)/CoAL-LDO catalysts (64.8% and 38.6%, respectively). The active components such as MnOx and Co3O4 are highly dispersed in the MnOx(0.25)/CoSn3Al-LDO catalyst. Sn doping increases the ratios of Mn4+/Mn3+ and Co3+/Co2+ as well as the adsorbed oxygen amount on the catalyst surface, and improves the redox capacity of the catalyst and increases the number of acid sites, resulting in the excellent low-temperature NH3-SCR performance of MnOx(0.25)/CoSn3Al-LDO.
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 Environmental Chemical Engineering
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2022
·
IF 7.968
Xinyu Li,Huawang Zhao,Yating Huang,Xiaomin Wu,Zhiwei Huang,Huazhen Shen,Guohua Jing
A composite catalyst was prepared by mechanically mixing Cu-SSZ-13 and MnCeTiO x to improve selective catalytic reduction (SCR) of NO x by ammonia. The optimal mass ratio of Cu-SSZ-13 and MnCeTiO x components in the composite catalysts was 1:1, where the NO x conversion was improved by around 40% in the temperature range of 150–300 °C compared with Cu-SSZ-13 alone. MnCeTiO x presented significantly stronger ability on the activation of NO to nitrates species than Cu-SSZ-13. Infrared (IR) and density functional theory (DFT) results showed that active nitrates intermediate on MnCeTiO x might migrate to Cu-SSZ-13, which assisted the oxidation of single Cu + to Cu 2+ to complete the Cu redox cycle. This avoided the rate-determining step that formation and oxidation of Cu + dimers in low-temperature SCR over Cu-SSZ-13. The research results are beneficial to the rational design of SCR catalysts with high-performance at low temperatures.
研究领域:
催化化学
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环境科学
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DOI
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 7
·3068
·
IF 4.6
Yuanyuan Ma,Wanting Liu,Zhifang Li,Yuhang Sun,Mingyuan Shi,Zheng Nan,Ruotong Song,Liying Wang,Jingqi Guan
TS-1 zeolite with desirable pore structure, an abundance of acidic sites, and good thermal stability promising as a support for the selective catalytic reduction of NO with NH3(NH3-SCR). Herein, a series of Mn–Fe/TS-1 catalysts have been synthesized, adopting tetraethylenepentamine (TEPA) as a metal complexing agent using the one-pot hydrothermal method. The introduced TEPA can not only increase the loading of active components but also prompts the formation of a hierarchical structure through decreasing the size of TS-1 nanocrystals to produce intercrystalline mesopores during the hydrothermal crystallization process. The optimized Mn–Fe/TS-1(R-2) catalyst shows remarkable NH3-SCR performance. Moreover, it exhibits excellent resistance to H2O and SO2at low temperatures. The characterization results indicate that Mn–Fe/TS-1(R-2) possesses abundant surface Mn4+and Fe2+and chemisorbed oxygen, strong reducibility, and a high Brønsted acid amount. For comparison, Mn–Fe/TiO2displays a narrower active temperature window due to its poor thermostability.Keywords:Mn-Fe/TS-1;one-pot synthesis;NH3-SCR;metal complexing;resistance to H2O and SO2
研究领域:
催化化学
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Yuting Hu,Minghu Zhao,Bo Du,Ting Cheng,Zhaozhong Jiang,Kai Qin,Chengzhu Zhu
A series of M-MnCeO X catalysts using MOF (Metal-organic Framework) were prepared to apply for NH 3 -SCR (Selective Catalytic Reduction) of NO X . The effects of Mn/Ce molar ratio, calcination temperature and its activity including catalytic activity, H 2 O/SO 2 resistance and stability were systematically investigated. The results showed that under the Mn/Ce molar ratio of 1 and calcination temperature of 400 ℃, the catalyst exhibited excellent catalytic activity, H 2 O/SO 2 resistance, and stability. When the concentration of NO was 500 ppm, the gas spatiotemporal velocity (GHSV) was 36,000 h −1 , and the reaction temperature was 100 ℃, the NO conversion efficiency of M-MnCeO X exceeded 90.0 %. Added 200 ppm SO 2 and 3 vol% H 2 O simultaneously, the NO conversion efficiency was close to 80.0 %. By analyzing the physicochemical properties of the catalyst, M-MnCeO X had a large specific surface area, numerous acidic sites, and excellent redox properties. According to density functional theory (DFT), the NH 3 /NO adsorption energy of M-MnCeO X were −2.35 and −2.40 eV, exhibiting lower than a single MOF-derivative, promoting the adsorption of NH 3 or NO. The reaction mechanism on the M-MnCeO X catalyst followed the E-R and L-H mechanisms by In situ DRIFTS.
研究领域:
环境催化
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材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Xuesong Liu,Peng Jiang,Yong Chen,Yaoguang Wang,Qiaoling Ding,Zhiming Sui,Hongfeng Chen,Zhongyun Shen,Xiaodong Wu
Two Ce-W-Ti mixed oxide catalysts were prepared by wet impregnation (CeW/Ti-I) and mechanical mixing (Ce/W/Ti-M) methods. CeW/Ti-I catalyst exhibits over 80% NO x conversion and nearly 100% N 2 selectivity at 200–550 °C. The superior catalytic performance is associated with the high dispersion of active CeO 2 and acidic WO 3 on TiO 2 and the synergistic effects among different components. The X-ray Diffraction, Raman spectroscopy, Nitrogen physisorption, X-ray photoelectron spectroscopy, H 2 temperature-programmed reduction, temperature-programmed desorption of ammonia and infrared spectroscopy were performed. It is found that the formation of solid solutions, as well as the high specific surface area, would increase the amounts of Ce 3+ , oxygen vacancies and acid sites in the catalyst. These broaden the operating temperature window of NH 3 -SCR reaction and enhance the N 2 selectivity by facilitating “fast SCR” reaction at low temperatures and inhibiting the unselective oxidation of NH 3 at high temperatures.
研究领域:
催化化学
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环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）