APPLIED CATALYSIS A-GENERAL
·
2021
·
IF 5.706
Min Zhao,Yihui Li,Ziang Zhao,Yuan Lyu,Wei Lu,Hejun Zhu,Yunjie Ding
Mn-doped spinel oxides CoAl 2 O 4 marked as CMA-m (m = Co/Mn atom ratio) herein were synthesized and evaluated for the first time as supports of Co-based Fischer-Tropsch synthesis (FTS) catalysts. HAADF-STEM images showed that Mn doping caused more crystal defects on the surface of CMA-m grains, which may provide more attachment sites for cobalt loading, leading to much smaller Co 0 particle size of 15Co/CMA-m than that of 15Co/CoAl 2 O 4 . Data of H 2 /CO chemisorption showed that the interaction of highly dispersed Co 0 with lattice Mn-doped CMA-m grain has a promotive effect on CO adsorption capability. FTS evaluation results demonstrate that 15Co/CMA-20 showed the highest CO conversion, C 5+ selectivity and C 5+ STY, benefiting from its high Co 0 dispersion and CO chemisorption capability as a result of suitable Mn doping into the lattice of CoAl 2 O 4 , which was confirmed very different from the influence of impregnated Mn oxide over CoAl 2 O 4 .
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Jichang Lu,Jian Fang,Zhizhi Xu,Dedong He,Siyou Feng,Yubei Li,Gengping Wan,Sufang He,Hua Wu,Yongming Luo
Supported MoS 2 based materials are widely used as heterogeneous catalysts. In this work, we propose a rapid and facile method (ultrasound-induced impregnation assisted by microwave thermal treatment) to synthesize mesoporous silica (SBA-15)-supported, few-layer, ordered and K-promoted MoS 2 nanosheets with different K/Mo ratios. The prepared catalysts are characterized by various physical and chemical techniques. Their catalytic performance is evaluated by methyl mercaptan (CH 3 SH) synthesis from CO/H 2 /H 2 S. The results show that our catalysts exhibit a much higher CO conversion and selectivity to CH 3 SH than the catalysts prepared using the conventional impregnation and reported in the literature. The good performance arises because of two main factors: MoS 2 nanosheets of only 2–4 layers and K promotion. Experimental characterizations and (density functional theory) calculations show that the former is the typical nano-size effect, and the latter stabilizes C S bonds when activating COS molecules.
研究领域:
催化材料
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Jiaxin Li,Yifei Liang,Zhao Li,Ke Fan,Chunxue Wang,Kai Li,Yuan Li,Xin Sun,Ping Ning,Fei Wang
The synthesis of methane from syngas represents a pivotal technology in the artificial synthesis of natural gas, with the study of methanation catalysts being a fundamental aspect of this process. Extensive research has focused on CO methanation using Ni/Al 2 O 3 catalysts; however, enhancements in catalyst stability and low-temperature activity are still required. This research investigated the structure of Ni/Al 2 O 3 under H 2 reduction at varying temperatures and the catalytic performance in natural gas synthesis (SNG) through CO methanation. It was observed that a higher reduction temperature resulted in nickel species agglomeration. Notably, Ni catalysts reduced at 600 °C demonstrated optimal CO conversion and CH 4 selectivity under the tested conditions. Characterization studies uncovered a synergistic effect between Ni and NiO species, which was most effective for catalytic activity under hydrogen reduction at 600 °C but only at an appropriate reduction temperature. These insights are significant for the advancement of Ni/Al 2 O 3 methanation catalysts in natural gas production .
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2019
·Vol. 33
·期 11
·e5208
·
IF 3.259
Baowei Wang,Chengyu Wang,Wenxian Yu
Mo 2 C/Al 2 O 3 catalyst was prepared by the impregnation method with urotropine and ammonium paramolybdate. The catalytic effect of Mo 2 C as a typical transition-metal carbide in sulfur-resistant methanation was studied. The catalysts prepared were characterized by N 2 adsorption–desorption, X-ray diffraction, transmission electron microscopy, H 2 -temperature-programmed reduction, and Raman spectra, with the results confirming the formation of β-molybdenum carbide on the surface of the catalysts. Studies on catalysts with different loading doses indicate that the optimal loading of Mo 2 C/Al 2 O 3 is about 15 wt.%, which enables CO conversion rate of up to 47%, with methane selectivity of up to 53%. This work further explored the effect of different concentrations of H 2 S in the raw gas on the performance of the catalyst, with the results showing that high concentration of H 2 S (>1500 ppm) can lead to sulfuration of active species on the catalyst, while resulting in a decrease in the catalytic activity.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Liqing Chen,Kejia Fan,Luting Yan,Jingfa Yang
Global economic and technological advancements have led to a significant surge in CO 2 emissions, posing severe environmental challenges. This study explores the photocatalytic reduction of CO 2 using a high-entropy fluorite oxide (HEFO), (Ce 0.2 Zr 0.2 Ti 0.2 Sn 0.2 Ca 0.2 )O 2-δ , synthesized via solid-state reactions. XRD, SEM, and XPS analyses confirmed a single-phase fluorite structure and revealed excellent light absorption (250–400 nm) with a 2.6 eV bandgap. Photocatalytic CO 2 reduction experiments demonstrated the superior performance of fine particles (72 % CO 2 conversion, 12.01 μmol h −1 g −1 methane generation, 61.2 % selectivity) compared to that of coarse one. This enhanced activity was attributed to a higher oxygen vacancy concentration, which optimized the surface electronic structure, increased the number of active sites, and improved CO 2 adsorption and activation. This study highlights the potential of HEFOs for renewable fuel production via CO 2 photoreduction.
研究领域:
环境科学
·
材料化学
·
催化
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Catalysis Science & Technology
·
2022
·Vol. 12
·期 14
·4624-4636
·
IF 6.177
Yi Yang,Weixin Qian,Haitao Zhang,Zhonghao Han,Hongfang Ma,Qiwen Sun,Weiyong Ying
FeMnxZr and FeMnxZr2Na catalysts prepared by coprecipitation and impregnation methods were applied to investigate the promoting effects of Zr on iron-based catalysts for high-temperature Fischer–Tropsch synthesis (HTFT). Ar physisorption and TEM demonstrated that Zr-promoted catalysts have a larger BET surface area and larger pore volume, which are more conducive to the distribution of active phases. Zr promoted the dispersity of iron particles and reduced the grain size of iron particles, resulting in the improvement of the FTS activity. The CO-TPD and MES results revealed that the introduction of Zr promoted the dissociative adsorption of CO, thereby promoting the formation of the active phase χ-Fe5C2 while suppressing the formation of ε′-Fe2.2C and further improving the FTS activity and the selectivity to C2=–C4= in the hydrocarbon distribution. However, the addition of an excessive amount of Zr caused the excess ZrO2 to cover the surface of the active site, inhibiting the CO dissociative adsorption and the formation of χ-Fe5C2, resulting in a decrease in the CO conversion and the selectivity to C2=–C4=. The XPS and H2-TPR results proved the interaction between Fe2O3 and ZrO2. And the Fe–ZrO2 interaction inhibited the coke deposition and aggregation of the Fe species, as confirmed by XRD and TEM, respectively. The FeMn5Zr2Na catalyst exhibited the highest C2=–C4= selectivity of 34.4% at a CO conversion of 96.3%. And FeMn5Zr2Na displayed the highest production of light olefins (441.6 g h−1 kgCat−1), which was significantly higher than FeMn2Na (162.2 g h−1 kgCat−1).
研究领域:
催化
·
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-11
·
IF 14.7
Li Hefei,Wei Pengfei,Liu Tianfu,Li Mingrun,Wang Chao,Li Rongtan,Ye Jinyu,Zhou Zhi-You,Sun Shi-Gang,Fu Qiang,Gao Dunfeng,Wang Guoxiong,Bao Xinhe
Producing valuable chemicals like ethylene via catalytic carbon monoxide conversion is an important nonpetroleum route. Here we demonstrate an electrochemical route for highly efficient synthesis of multicarbon (C 2+ ) chemicals from CO. We achieve a C 2+ partial current density as high as 4.35 ± 0.07 A cm −2 at a low cell voltage of 2.78 ± 0.01 V over a grain boundary-rich Cu nanoparticle catalyst in an alkaline membrane electrode assembly (MEA) electrolyzer, with a C 2+ Faradaic efficiency of 87 ± 1% and a CO conversion of 85 ± 3%. Operando Raman spectroscopy and density functional theory calculations reveal that the grain boundaries of Cu nanoparticles facilitate CO adsorption and C − C coupling, thus rationalizing a qualitative trend between C 2+ production and grain boundary density. A scale-up demonstration using an electrolyzer stack with five 100 cm 2 MEAs achieves high C 2+ and ethylene formation rates of 118.9 mmol min −1 and 1.2 L min −1 , respectively, at a total current of 400 A (4 A cm −2 ) with a C 2+ Faradaic efficiency of 64%.
研究领域:
电化学
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催化
·
材料科学
·
能量转换
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF CATALYSIS
·
2024
·
IF 6.5
Yuxi Meng,Shaomian Liu,Yixi Wang,Wenqing Xu,Jiajian Gao,Sansan Yu,Fabing Su,Tingyu Zhu
Selective catalytic reduction of NO using CO (CO-SCR) is a promising technology for the purification of NO in the flue gas. However, the presence of O 2 significantly inhibits the activity of the CO-SCR catalyst. Herein, we synthesize a hollow Mn-doped CeO 2 @Co 3 O 4 catalyst (Mn-CeO 2 @Co 3 O 4 ), which achieved 82% NO conversion, 100% CO conversion, and 78% N 2 selectivity under 5 vol% O 2 at 200 °C, superior to those of CeO 2 @Co 3 O 4 and Co 3 O 4 @CeO 2 catalysts. The characterization results indicate that the strong electronic interaction at the heterointerfaces between Co 3 O 4 and CeO 2 plays a crucial role in promoting selective adsorption of NO. Furthermore, the Mn doping into the Co 3 O 4 lattice of the catalyst facilitates the conversion of N 2 O intermediates, thereby enhancing the overall activity. This research provides a new strategy for the design and synthesis of CO-SCR catalysts.
研究领域:
催化
·
环境科学
·
材料科学
✓ 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）