Journal of Energy Chemistry
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2017
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IF 2.594
Zhaopeng Liu,Yan Xu,Zhenhua Li,Baowei Wang,Weihan Wang,Xinbin Ma,Renjie Liu
In this paper, Ce 0.2 Zr 0.8 O 2 composite supports were prepared by different Ce-addition methods including impregnation of cerium (CeZr-imp), impregnation of citric acid and cerium (CeZr-CA) simultaneously and deposition precipitation method (CeZr-DP), respectively. The as-prepared supports were applied to prepare 10 wt% MoO 3 /Ce 0.2 Zr 0.8 O 2 catalysts for sulfur-resistant methanation . The N 2 adsorption/desorption, X-ray diffraction (XRD), Raman spectroscopy (RS), X-ray photoelectron (XPS), temperature-programmed reduction by hydrogen (H 2 -TPR) were undertaken to get textural properties, morphological information and structures of the catalysts. The results showed that MoO 3 was highly dispersed on the surface of these three supports and Ce was mostly of coexisted in Ce 4+ /Ce 3+ redox pairs. Compared with Mo/CeZr-imp, the CO conversion increased by 10% and 15% for Mo/CeZr-CA and Mo/CeZr-DP, respectively. This was mainly attributed to the larger specific surface area, Ce 3+ concentration and content of active MoS 2 on the surface of catalysts.
研究领域:
催化化学
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材料科学
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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
Shuangxi Lin,Longchen Gong,Ning Zhao,Huibo Zhao,Feigang Zhao,Yang Bai,Zhenhua Li,Wen Liu
Modulating metal-support interactions is critical for improving catalytic activity and product selectivity for CO 2 hydrogenation. Such modulation can be achieved by modifying the metal nanoparticles as well as the supports. Here, we prepared a novel catalyst, in which Ni nanoparticles were dispersed on CeO 2 and hexagonal boron nitride (h-BN) hybrid supports. The introduction of h-BN to Ni/CeO 2 -BN effectively improves the dispersion of Ni nanoparticles. More importantly, the abundant Ni-CeO 2 interfacial sites with enriched oxygen vacancies are formed over h-BN edge sites. The dispersed Ni species are anchored on CeO 2 via a unique interfacial structure, with electron-rich Ni (Ni δ− ) species. At the interfacial sites on Ni/CeO 2 -BN, the synergy between oxygen vacancies and Ni δ− , which enhances CO 2 activation and H 2 dissociation, respectively, renders superior catalytic performance for CO 2 methanation. In situ DRIFTS suggests formate as key rate-limiting intermediates on Ni-CeO 2 sites, while the formation of B-H bonds further promotes hydrogen activation and subsequently the catalytic performance. The modulation of metal-support interactions by spatial confinement effect by BN offers a new paradigm for designing metal/oxide catalysts for chemical transformations that requires bifunctionality as CO 2 hydrogenation.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2024
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IF 7.1
Linjia Li,Yiran Zhang,Jiaqi Feng,Shu Zhao,Wei Qiu,Ke Li,Zhen Huang,He Lin
Derived from carbon capture, utilization, and storage (CCUS), integrated carbon capture and utilization (ICCU) has been widely developed recently. Understanding the influences of H2O, O2, and NO2 on dual-function materials (DFMs) performance is crucial for their practical application. In this study, the influence mechanisms of O2, H2O, and NO2 on CeNiCa DFM for ICCU-methanation are investigated. The catalyst was oxidized by O2, H2O, and NO2. NO2 competes with CO2 for basic adsorption sites, inhibiting CO2 adsorption and methanation, but adsorbed NO2 is reduced mainly to N2 and NH3 during methanation. H2O induces agglomeration of the adsorbent and catalyst─the former due to the Ca(OH)2 mobility, and the latter attributed to OH-promoted migration and agglomeration of Ni. On this basis, it is proposed that the dominant roles of H2O, O2, and NO2 change in two- and multi-interference components, but the joint effects among them should not be neglected.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
Catalysts
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2017
·Vol. 7
·期 1
·21
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IF 3.082
Yang Han,Bo Wen,Mingyuan Zhu
In this study, we prepared core-shell structured Ni@SiO2catalysts using chemical precipitation and modified Stöber methods. The obtained Ni@SiO2samples exhibited excellent catalysis performances, including high CO conversion of 99.0% and CH4yield of 89.8%. Moreover, Ni@SiO2exhibited excellent catalytic stability during a 100 h lifetime test, which was superior to that of the Ni/SiO2catalyst. The prepared samples were characterized using a series of techniques, and the results indicated that the catalytic performance for syngas methanation reaction of the Ni@SiO2sample was markedly improved owing to its nanoreactor structure. The strong interaction between the Ni core and the SiO2shell effectively restrained the growth of particles, and the deposition of C species.Keywords:syngas methanation;Ni@SiO2;anti-carbon deposition;catalytic stability
研究领域:
化学工程
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催化材料
✓ 已验证
DOI
高影响因子
Molecular Catalysis
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2023
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IF 4.6
Dou Zhang,Bo-hui Li,Yi-lei Li,Jun Zhao,Xiao-jing Wang,Fa-tang Li
The efficient conversion of CO 2 to carbon-neural fuels by photocatalysts can effectively address the increasingly prominent challenges of environmental pollution and energy shortage. TiO 2 is considered a promising photocatalyst. However, its disadvantages, such as poor adsorption of CO 2 and low carrier separation efficiency, inhibit its performance and selectivity in photocatalytic CO 2 reduction. Herein, K + -modified anatase TiO 2 ultrathin nanosheet photocatalysts were obtained via a reverse etching method using K 2 Ti 8 O 17 as the precursor. The selectivity of the optimized photocatalyst for methane was 96.02% in a gas–solid system without additives, with an excellent photocatalytic rate of 42.3 μmol·g −1 ·h −1 , which was 3.39 times higher than that of P25. The effects of K + on photocatalytic behaviors and the selectivity of CH 4 was systematically investigated. The test results showed that during treatment with formic acid, a large amount of K + from the layered K 2 Ti 8 O 17 were removed and the original structure was destroyed. Therefore, highly dispersed TiO 2 nanosheets were obtained, with a small amount of K + remaining on the TiO 2 surface. The well-defined rectangular shapes of TiO 2 reduce the transmission distance of photogenerated carriers, whereas the presence of K + increase the chemisorption of CO 2 molecules, thereby activating CO 2 , promoting the conversion of bridge *CO to -CHO, and increasing CH 4 production. This study provides insightful references for the preparation and modification of traditional photocatalysts for photocatalytic CO 2 reduction reactions.
研究领域:
材料科学
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环境科学
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能源科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2017
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IF 9.446
Wenhui Li,Xiaowa Nie,Xiao Jiang,Anfeng Zhang,Fanshu Ding,Min Liu,Zhongmin Liu,Xinwen Guo,Chunshan Song
Screening of various supports reveals that Co catalysts supported on ZrO 2 and Al 2 O 3 show good initial activity for CO 2 methanation. Co/ZrO 2 and Co/Al 2 O 3 catalysts prepared by impregnation with different metal loadings were further examined comparatively. The 10Co/ZrO 2 catalyst showed high activity with CO 2 conversion of 92.5% and CH 4 selectivity of 99.9% without deactivation after 300 h time on stream (TOS). However, the 10Co/Al 2 O 3 catalyst gave a lower CO 2 conversion of 77.8% which decreased to 38.6% after 300 h TOS. The catalysts were characterized by STEM/EDS (scanning transmission electron microscopy/energy-dispersive X-ray spectroscopy), in situ XRD(X-ray diffractometer), H 2 -TPR(temperature programmed reduction), XPS (X-ray photoelectron spectroscopy), chemisorption of H 2 , CO, CH 4 , CO 2 and NH 3 -TPD (temperature programmed desorption). Re-dispersion of Co species on the ZrO 2 support during reduction by H 2 was observed by STEM/EDS. New Co-Zr phase formed on the Co-ZrO 2 interface was directly observed by TEM for the first time; the Co/ZrO 2 catalyst exhibited high stability with high activity for CO 2 conversion. In situ XRD, H 2 -TPR and XPS results indicate the promoting effect of ZrO 2 on the reduction of Co 3 O 4 to Co metal along with the negative effect of Al 2 O 3 . The oxygen vacancies on the ZrO 2 detected by XPS may help to activate CO 2 and H 2 O and resist deactivation. Co/Al 2 O 3 catalyst deactivates rapidly due to coke deposition and spinel formation.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2017
·Vol. 122
·期 1
·525-538
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IF 1.264
Li Xin,Meng Fanhui,Cheng Yang,Gao Yuan,Li Zhong
Mesoporous silica (SiO 2 ) supported highly dispersed Ni catalysts with ZrO 2 and surfactant β-cyclodextrin (CD) were prepared by the impregnation method, and their catalytic performance for three-phase methanation of CO were evaluated. It is shown that ZrO 2 promotes the dispersion of Ni species on mesoporous SiO 2 , leading to the increase in Ni dispersion and methanation activity. For the ZrO 2 content, the optimum is 5 wt%. Moreover, when adding CD in the preparation of Ni5Zr/SiO 2 catalyst, CD was found effectively enhanced the dispersion of Ni species and interaction between Ni species and support, leading to a smaller size of NiO particles and more exposed active surfaces, which promotes the CO adsorption capacity. As the molar ratio of CD/Ni rises, the crystallite size of metallic Ni decreased. Ni5Zr/SiO 2 (1:5) catalyst prepared with 5 wt% ZrO 2 and 1:5 molar ratio of CD/Ni shows the optimal catalytic activity for the three-phase CO methanation reaction. This is because of the highest dispersion of metallic Ni and smallest size of NiO particles.
研究领域:
化学工程
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催化
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材料科学
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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
Zongze Lv,Jiaqi Ruan,Weifeng Tu,Xun Hu,Donglin He,Xin Huang,Changlei Qin
Integrated carbon capture and utilization by methanation (ICCU-methanation) is an emerging concept in reducing CO 2 emissions and storing H 2 simultaneously. One key of the technology is the development of dual functional materials (DFMs) that can efficiently capture CO 2 and then catalyze it. Herein, we propose the construction of DFM using Li 4 SiO 4 with superior CO 2 adsorption/desorption features as sorbent and catalyst carrier, CeO 2 as catalyst promoter and isolator, and Ni as catalytic metal, and comprehensively evaluate its characteristics and performance in ICCU-methanation. Results show that the DFM developed possess a high and stable CO 2 capacity of 5.4 mmol·g DFM -1 , 96 % CO 2 conversion and 96 % CH 4 selectivity under both the ideal CO 2 capturing atmosphere and the realistic flue gas containing 10 vol% steam and 8 vol% O 2 . Moreover, rapid CO 2 dissociation from the DFM is observed at a temperature lower to 560 °C due to the reaction of H* dissociated by catalyst with carbonate to form formate, which further decomposes to release CO.
研究领域:
能源化学
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环境科学
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DOI
高影响因子
Journal of CO2 Utilization
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2019
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IF 5.189
Shanshan Chai,Yong Men,Jinguo Wang,Shuang Liu,Qiaoling Song,Wei An,Gunther Kolb
Catalytic reduction of CO 2 to methane has been recognized as one of the most important strategic reactions to produce highly valuable chemicals and for storage of renewable energy (power-to-gas). This study demonstrates a crystal facet-dependent catalytic reduction of CO 2 to CH 4 on ruthenium nanoparticles deposited over TiO 2 nanocrystal with exposed (001) and (101) facets. Compared with TiO 2 (101) nanocrystal with the same Ru loading, Ru nanoparticles supported by TiO 2 (001) exhibited a highly enhanced CO 2 conversion rate and significantly improved methanation reactivity, along with a considerable durability. The physicochemical properties of the samples were characterized by HR-TEM, XRD, BET, FT-IR, UV–vis, Raman, ICP, and temperature-programmed reaction with CO 2 , and CO 2 + H 2 . In view of the difference in catalytic activity and the physicochemical properties of the supported Ru/TiO 2 catalysts, the results uncovered that the nature of the catalyst support of Ru/TiO 2 strongly affected the dispersion of Ru species and the synergistic effect between Ru and underlying TiO 2 supporting materials due to the strong metal-support interaction, and thus affected their capability to activate CO 2 and determined the catalytic activity for CO 2 methanation. Our work demonstrated the important role of the exposed crystal facets of the underlying support and the resulting Ru particle which had a large effect on CO 2 methanation.
研究领域:
催化化学
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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
CATALYSIS COMMUNICATIONS
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2022
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IF 3.51
Bin Chen,Jian Qiu,Liang Xu,Yan Cui
The Ni/Ce 0.8 Zr 0.2 O 2 catalysts with different Ni doping amounts (5 wt%, 10 wt%, 15 wt%, 20 wt%, and 25 wt%) are prepared by the impregnation technique and used as CO 2 methanation catalysts in this work. The effects of various Ni doping loading on CO 2 methanation catalytic performance at low temperatures were investigated in this catalytic system. The results show that the catalyst with 15 wt% Ni doping shows the best catalytic performance. Since the heated sintering of Ni nanoparticles was prevented efficiently by CO 2 methanation, these mesoporous catalysts exhibit excellent stability. Therefore, the catalyst is expected to be an efficient CO 2 methanation catalyst at low temperatures.
研究领域:
催化
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环境化学
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材料科学
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产品关联
DOI
高影响因子
Journal of CO2 Utilization
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2019
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IF 5.189
Haoxi Jiang,Qiang Gao,Shutian Wang,Yifei Chen,Minhua Zhang
Carbon dioxide methanation is of great importance for both environment and energy because of the reduction of carbon dioxide emissions and the utilization of carbon source. In this work, UiO-66 was employed as the support for palladium nanoparticles via a sol-gel method to enhance the activity of CO 2 methanation. The physical-chemical properties of as-prepared catalysts were characterized using N 2 adsorption-desorption, X-ray diffraction (XRD), transmission electron microscope (TEM), temperature programmed desorption (TPD), temperature programmed reduction (TPR), thermo-gravimetric analysis (TGA), Fourier-transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). It was found that there was a synergistic effect between UiO-66 and supported Pd. CO 2 could be activated in UiO-66 via its Zr 6 O 4 (OH) 4 nods, while H 2 molecules were dissociated at Pd for further hydrogenation of activated CO 2 . As a result, the catalyst with a Pd loading of 6 wt.% exhibited a high activity with 56.0% of CO 2 conversion and 97.3% of CH 4 selectivity, corresponding to a STY of 856 g·h −1 ·kg cat −1 at 4 MPa and 340 °C.
研究领域:
环境科学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2024
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IF 6.3
Min Chen,Longgang Liu,Xueyan Chen,Xiaoxiao Qin,Kunlin Li,Jianghao Zhang,Xiaolei Bao,Lingjuan Ma,Changbin Zhang
The influence of metal particle size over heterogeneous catalysts on the catalytic performance has always been an interesting subject due to its significance from both fundamental and practical perspectives. In this work, we regulated the synthesis of TiO 2 by the hydrolysis of different titanium precursors, and as-prepared TiO 2 supports were employed to load Ru with impregnation method. Interestingly, we synthesized three Ru-TiO 2 catalysts with different Ru particle sizes of 1.1, 2.9 and 5.2 nm. The Ru-TiO 2 catalysts were next tested for CO 2 hydrogenation reaction, the results show that the medium Ru particles on TiO 2 exhibited the best CO 2 methanation activity. Based on the characterizations, we observed that the medium Ru particles exhibited the best redox properties compared with small and large Ru particles, which was beneficial to the H 2 dissociation; in addition, the medium Ru particles exhibited a moderate ability to activate CO 2 , resulting in the most favorable formation and decomposition of bidentate bicarbonate. Consequently, the Ru-TiO 2 catalyst with medium Ru particles showed the highest activity for CO 2 methanation. This study provides a new method to prepare Ru-TiO 2 catalysts with different Ru sizes and also presents an understanding of Ru particle size effects on CO 2 hydrogenation.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子