ACS Catalysis
·
2022
·
IF 13.7
Danfeng Wu,Sixu Liu,Mingqi Zhong,Jiafei Zhao,Congcong Du,Yanling Yang,Yifei Sun,Jingdong Lin,Shaolong Wan,Shuai Wang,Jianyu Huang,Yali Yao,Zhe Li,Haifeng Xiong
Metal single-atom catalysts (SACs) have attracted extensive interest because of their maximum atom efficiency and potentially good performances. However, the understanding of the catalytic behavior and the stability of SACs in high-temperature catalytic reactions remains a major challenge, especially under reducing conditions. In this work, we investigated the nature and stability of Rh/CeO2 SACs with different Rh loadings (0.2–4 wt % Rh) during syngas conversion (260 °C, 2 MPa). Using CO-DRIFTS, we found that atomically dispersed Rh was dispersed on Rh/CeO2 catalysts with an Rh loading up to 3 wt %. The Rh/CeO2 catalysts were stable in H2 up to 350 °C, while Rh nanoclusters were formed in CO at 200 °C. During syngas conversion at 260 °C, the Rh single atoms (Rhiso) on a 0.5 wt % Rh/CeO2 SAC slowly agglomerated to form Rh nanoclusters (RhNC) and a Rhiso/RhNC ratio of ∼1:2.5 was obtained after ∼10 h time-on-stream run. Furthermore, the Rhiso/RhNC ratio did not change with further reaction, indicating that the reaction reached steady state after a 10 h run. After the catalysts reached steady state (∼10 h), the Rhiso/RhNC ratio on the spent Rh/CeO2 catalysts decreased with the increase in Rh loadings, while the reactivity increased first and then decreased. We observed an optimal value of Rhiso/RhNC ≈ 1:3 on the 1 wt % Rh/CeO2 catalyst, showing the maximum reaction rates of CO (rCO) and ethanol selectivity (SEtOH) of 85.8 μmol/s/gRh and 26.2%, respectively. This indicated that the combination of Rh single atoms and Rh nanoclusters is beneficial to the ethanol selectivity and reaction rate, which was confirmed by DFT simulations. Moreover, the ratios of Rhiso/RhNC on the spent catalysts under the steady state have good relationships with the CO conversion rate and product selectivity in the reaction.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
Arabian Journal of Chemistry
·
2022
·
IF 6.212
Lusheng Shi,Pengquan Yan,Zhihua Gao,Wei Huang
Due to the complexity of the structure–activity relationship of the CuAl 2 O 4 spinel catalyst, optimization of the catalyst structure is a great challenge. In this paper, three different CuAl 2 O 4 spinel catalysts were prepared by the solid-phase method using copper hydroxide, copper nitrate, and copper oxide as the copper source, respectively, to study the difference in the structure of CuAl 2 O 4 spinel catalysts induced by the raw materials and the catalytic behavior for CO hydrogenation. The structure of CuAl 2 O 4 spinel catalyst was characterized by XRD, BET, SEM, TEM, H 2 -TPR and XPS. The activity of CO hydrogenation over the CuAl 2 O 4 spinel catalyst without pre-reduction was evaluated in the slurry reactor. The results demonstrated that different copper sources had obvious influence on the CuAl 2 O 4 spinel texture properties, surface enrichment degree, as well as decomposition and reduction ability, which further regulated the ratio of Cu + /Cu 0 and thus affected the catalytic performance, especially the alcohol distribution. The CuAl 2 O 4 spinel, employing copper hydroxide as the copper source, showed better selectivity of C 2+ OH, which was assigned to a higher ratio of Cu + /Cu 0 , along with larger pore size and pore volume. Moreover, the synergistic effect between Cu 0 and γ-Al 2 O 3 improved the selectivity of dimethyl ether.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2023
·
IF 12.9
Nana Gong,Tao Zhang,Minghui Tan,Liyan Wang,Jiaqian Yang,Li Tan,Guohui Yang,Peng Wu,Yingquan Wu,Yisheng Tan
CO hydrogenation to isobutyl alcohol is a promising route for CO transformation to high value-added products. However, the formation mechanism of isobutyl alcohol is complex, and its synthesis requires complex catalysts and harsh reaction conditions, which hinders the identification of active sites. Herein, we efficiently synthesized isobutyl alcohol under mild conditions over a simple Cu–ZrO2 catalyst by decreasing the Cu loading. The space–time yield (STY) of isobutyl alcohol using an optimal CZ-0.11 catalyst was as high as 61.3 g·Lcat–1·h–1 with a CO conversion of 19.2%, far surpassing the STY of the state-of-the-art isobutyl alcohol synthesis (44.6 g·Lcat–1·h–1) under harsh conditions. Decreasing the Cu loading increased the distribution of smaller Cu particles and clarified the structure–activity relationship of Cu–Zr interactions for isobutyl alcohol synthesis. The enhanced Cu–Zr interaction led to the formation of more electron-deficient Cu species on the CZ-0.11 catalyst, which enriched the linearly adsorbed CO on Cu, as demonstrated by in situ diffuse reflectance infrared Fourier-transform spectroscopy. Experimental and theoretical results revealed that coupling of the bicarbonate species on ZrO2 with the linearly adsorbed CO species on electron-deficient Cu clusters promoted the formation of C2 intermediates and finally produced isobutyl alcohol through rapid β-addition. These insights into the active sites for CO hydrogenation to isobutyl alcohol may guide further catalyst designs.
研究领域:
催化化学
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能源化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ChemPlusChem
·
2025
·
IF 2.8
Chunqiu Zhao,Qiang Chang,Fu Yin,Guowei Niu,Chenghua Zhang,Dan Liu,Bhekie B. Mamba,Alex T. Kuvarega
Graphical To enhance the catalytic performance of Zn−NC in the hydrogenation of CO to dimethyl ether, highly dispersed bimetallic catalysts are synthesized through the pyrolysis different metal-doped ZIF. The incorporation of secondary metals (Mn, Fe, Co, Ni, Cu) leads to distinct variations in catalytic performance. Among them, the introduction of Cu significantly improves catalytic activity. Highly dispersed bimetallic atomic-scale catalysts have garnered significant attention in syngas conversion filed due to the synergistic effects of the precisely structured bimetallic site, which facilitate the effective activation of CO. Despite their potential, synthesizing these catalysts to meet the specific application requirements remains challenging. Herein, various bimetallic catalysts were synthesized through the pyrolysis of the bimetallic ZIF precursors which were prepared by in situ doping of different metals (Mn, Fe, Co, Ni and Cu) into the ZIF-8 structure. In the presence of a highly dispersed and highly loaded Zn, the doping content in the ultimate second metallic catalysts varied between 0.15–1.20 wt % for different metals. The catalysts were systematically characterized using XRD, BET, TEM, XPS, Raman, ICP, and H 2 -TPD techniques. Among them, the Zn−NC regulated with Cu or Ni exhibited superior catalytic performance. Notably, the Cu−Zn−NC catalyst showed the highest activity, achieving a CO conversion of 32.8 % and optimal DME selectivity approaching 95.2 % in CO hydrogenation reactions. These enhanced performance metrics were attributed to the synergetic effects of bimetallic components. The incorporation of Cu not only preserved the original Zn−N structure but also preserved the catalytic performance unchanged. This preparation strategy is expected to filter out new research targets to use in diverse catalytic applications.
研究领域:
催化化学
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材料科学
·
能源化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2022
·
IF 4.383
Jingrong Wang,Zhihua Gao,Pengquan Yan,Yaxing Shen,Rui Yang,Zhijun Zuo,Wei Huang
CuO with a large microcrystalline differentiation was prepared by hydrothermal method , and the activity of the CuZnAl catalysts prepared by combining CuO with ZnAl was tested in the CO hydrogenation reaction. The effect of Cu species crystallite size on catalytic structure and performance was revealed. The experimental results show that CuO crystallite grow with the raising of hydrothermal temperature. When the hydrothermal temperature was 130 °C, CZA-130 exhibited the stable crystallite size of Cu species, high Cu/Zn molar ratio, and strong interaction between copper and zinc oxide, so the selectivity of total alcohol could reach up to 71.39%. Moreover, the ratio of C 2+ OH in the alcohol product is positively correlated with higher ratio of Cu + /Cu 0 and total number of alkalis, which are related to the ability of growing carbon chain.
研究领域:
化学工程
·
催化科学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2018
·Vol. 11
·期 3
·1123-1130
·
IF 4.674
Xiao-Li Li,Guo-Hui Yang,Meng Zhang,Xiao-Feng Gao,Hong-Juan Xie,Yun-Xing Bai,Ying-Quan Wu,Jun-Xuan Pan,Yi-Sheng Tan
Graphical Tuning selectivity : Cu/SiO 2 was prepared by ammonia evaporation and used as catalyst for the direct synthesis of ethanol from CO hydrogenation. Both the Cu + /(Cu + +Cu 0 ) values and copper crystallite sizes had significant effects on the selectivity towards ethanol. Cu/SiO 2 catalyst was prepared by the ammonia evaporation method for the direct synthesis of ethanol from CO hydrogenation. The catalyst exhibited the initial ethanol selectivity as high as 40.0 wt %, which dramatically decreased from 40.0 to 9.6 wt % on the stream of 50 h. XRD, XPS, TEM and N 2 O titration techniques were employed to elucidate the ethanol selectivity change and catalyst structure evolution during reaction process. The experiment and characterization results indicated that both Cu + /(Cu + +Cu 0 ) value and copper crystallite size had great effects on the ethanol selectivity. During the initial 38 h, the ethanol selectivity obviously decreased from 40.0 to 18.2 wt %, and Cu + /(Cu + +Cu 0 ) value on the catalyst surface rapidly dropped from 0.67 to 0.39, while the copper crystallite size remained almost unchanged. However, during the reaction period of 38–50 h, the Cu + /(Cu + +Cu 0 ) value possessed no distinct change, but a further decrease in ethanol selectivity and a rapid aggregation in Cu particles were observed simultaneously. The present systematic investigation demonstrated that the decrease of Cu + /(Cu + +Cu 0 ) value was the main factor for the loss of ethanol selectivity during the initial 38 h, whereas the rapid growth of Cu particles during the reaction period of 38–50 h were mainly contributed to the further decline of ethanol selectivity.
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
Journal of Physical Chemistry C
·
2017
·
IF 4.536
Xin Liang,Zhibo Ren,Xiaolin Zhu,Qinwei Zhang,Donghai Mei,Biaohua Chen
A dramatic morphology evolution from cobalt nanoparticles to one-dimensional cobalt nanochains have been found by the introduction of CO in the synthesis process. The competitive adsorption between oleylamine (OAm) and CO molecules on cobalt surface was analyzed by DFT calculations. The competitive adsorption provides an effective way to regulate the surface properties of cobalt nanoaparticles, thus adjusting the interactions between cobalt nanoparticles and leading the self-assembly formation of cobalt nanochains. The novel one-dimensional cobalt nanochains show superior activity for CO hydrogenation, thus providing a powerful strategy for the surface and morphology controlled synthesis of catalyst nanomaterials assisted by small molecules.
研究领域:
材料科学
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催化化学
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理论计算化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2025
·Vol. 15
·期 33
·26950-26958
·
IF 4.6
Chunqiu Zhao,Qiang Chang,Fu Yin,Jing Li,Guowei Niu,Hulin Wang,Dan Liu,Bhekie B. Mamba,Chenghua Zhang,Alex T. Kuvarega
One-step CO hydrogenation to value-added chemicals represents a prominent yet challenging research objective for conventional catalysis processes in chemical industry. Herein, we report a rationally designed Ni-doped Zn-NC catalyst embedded within an N-doped carbon matrix for one-step CO hydrogenation to dimethyl ether (DME), demonstrating superior CO conversion compared to the pristine Zn-NC catalyst (25.9% vs. 20.6%) while both maintaining high DME selectivity (>93%). Structural characterization revealed that Ni atoms existed in a bimetallic coordination environment, which is crucial for the promoting effect of Ni. In contrast, Ni nanoparticles incorporated into Zn-NC (nanoNi–Zn-NC) reduced CO conversion to less than 17% despite retaining high DME selectivity (>92%). Besides, control catalysts containing either Ni-only or Ni/Zn nanoparticles supported on carbon support exhibited limited catalytic activity and mainly produced hydrocarbons. This work provides valuable insights into the active sites of the bimetallic Ni–Zn-NC catalysts and elucidate the structural effects of bimetallic systems for CO conversion to DME. Furthermore, this study offers a feasible framework for optimizing Zn-based bimetallic catalysts.
研究领域:
催化化学
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化学工程
·
材料科学
·
能量转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Wanliang Yang,Meng Chen,Jiayuan Zhou,Yingnan Duan,Yinmin An,Mao Liu,Mengkui Tian
Porous carriers play an important role in the catalytic transformation of syngas into higher alcohols, which promises higher sustainability in C1 chemistry. In this work, a series of hierarchical hollow silica spheres (HHSS) supported Cu-Fe bimetal catalysts were successfully prepared through ultrasonic-assisted impregnation for higher alcohols synthesis from syngas. Structural characterization results indicate that the hierarchical hollow structure of HHSS support can be maintained and the Cu-Fe bimetallic nanoparticles are highly dispersed on HHSS surface. The catalytic performances of samples in the test of CO hydrogenation for higher alcohols synthesis were investigated. The results revealed that the conversion rate of CO and the selectivity of C 2+ OH alcohol increased first and then decreased with the decrease of the amount of Cu content in the Cu x Fe y @HHSS catalyst. The highest CO conversion, alcohol selectivity and STY ROH over Cu-Fe@HHSS catalyst are 65.1 %, 46.6 %, and 118.1 gkg −1 h −1 , respectively. It was found that a large number of CuFe 2 O 4 were formed in Cu-Fe@HHSS catalyst and also confirmed that the CuFe 2 O 4 spinel and CuO-CuFe 2 O 4 were converted to Cu-Fe 5 C 2 composite in the spent Cu-Fe@HHSS catalyst, which can enhance the synergy between Cu-Fe bimetals. Furthermore, copper and iron are highly dispersed on HHSS after the reaction, which enhances the structural stability of the catalyst. Based on the development and utilization of low-cost catalysts and the production of clean liquid fuels, HHSS has a great prospect of catalyst support in the energy field.
研究领域:
催化化学
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能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Kejing Wang,Yongjun Liu,Zhiwen Li,Nan Cui,Lei Sun,Wei Huang
The valence states of Cu site are regarded as an important factor affecting the performance of syngas to higher alcohols (C 2+ OH). Regrettably, the role of Cu 0 and Cu + in CO hydrogenation to higher alcohols remains controversial due to the complexity of the reaction. In this study, Cu 0 and Cu 2 O powders are directly added as the precursors to adjust the ratios of Cu + /(Cu 0 +Cu + ) and Cu particle sizes in CuZnAl catalysts by a complete liquid-phase (CLP) technology. The CAT-Cu 0 catalyst with higher Cu 0 content shows the highest CO conversion (>15%) ascribing to the biggest S Cu , but is also accompanied by the highest CO 2 selectivity (>40%), while the CAT-Cu + catalysts with higher Cu + content displays relative better C 2+ OH selectivity (>60%) and stability due to a higher probability of CO insertion. In-situ DRIFTS experiments reveal that a synergy between larger Cu particle sizes (30～40 nm) and surface Cu + sites, in which larger Cu sizes enhances the probability of bridge CO adsorption, thereby favoring the C–O bond dissociation for CH x formation. Meanwhile, Cu + active sites provide a higher probability for CO/CHO insertion to form CH 3 CHO*/CH 2 CO* intermediates. This study further deepens our understanding of the critical controlling factors for highly selective synthesis of C 2+ OH from syngas over Cu-based catalysts.
研究领域:
化学工程
·
催化
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2024
·
IF 5.8
Heyun Lin,Wenzhe Zhang,Huachen Shen,Hailing Yu,Yunlei An,Tiejun Lin,Liangshu Zhong
The catalytic behavior of CO hydrogenation can be modulated by metal–support interactions, while the role of the support remains elusive. Herein, we demonstrate that the presence of strong metal–support interactions (SMSI) depends strongly on the crystal phase of TiO2 (rutile or anatase) and the treatment conditions for the TiO2 support, which could critically control the activity and selectivity of Ru-based nanocatalysts for CO hydrogenation. High CO conversion and olefin selectivity were observed for Ru/rutile-TiO2 (Ru/r-TiO2), while catalysts supported by anatase (a-TiO2) showed almost no activity. Characterization confirmed that the SMSI effect could be neglected for Ru/r-TiO2, while it is dominant on Ru/a-TiO2 after reduction at 300 °C, resulting in the coverage of Ru nanoparticles by TiOx overlayers. Such SMSI could be suppressed by H2 treatment of the a-TiO2 support and the catalytic activity of the as-obtained Ru/a-TiO2(H2) can be greatly elevated from almost inactive to >50% CO conversion with >60% olefin selectivity. Further results indicated that the surface reducibility of the TiO2 support determines the SMSI state and catalytic performance of Ru/TiO2 in the CO hydrogenation reaction. This work offers an effective strategy to design efficient catalysts for the FTO reaction by regulating the crystal phase of the support.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Pengchao Ren,Weifeng Tu,Chanchan Wang,Sifan Cheng,Wenqi Liu,Zhenzhou Zhang,Yun Tian,Yi-Fan Han
This study investigated the Cu-CeO 2 interactions for CO hydrogenation to methanol by applying rate measurements, chemical titration/desorption, together with in-situ/operando spectroscopy techniques under realistic reaction conditions. Ce components were enriched in the surface region of Cu/CeO 2 catalysts while Ce 3+ and Ce 4+ atoms co-existed during CO hydrogenation. The ratio of Ce 3+ to Cu 0 in the surface region of catalysts increased linearly with the Ce content. The turnover rates of CH 3 OH formation increased as a single-valued function of the ratio, irrespective to the individual contact extent between Cu and CeO 2 clusters or Ce content in the Cu/CeO 2 catalysts, indicating that the Cu 0 -Ce 3+ sites pair acts as active sites for CO hydrogenation to methanol over Ce-CeO 2 samples. This study also unraveled that formyl and formate species, as reactive surface intermediates, were co-adsorbed on the Cu 0 -Ce 3+ sites, and their hydrogenation routes occurred concurrently for CH 3 OH formation during CO-H 2 reactions.
研究领域:
催化
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化学工程
·
表面科学
✓ 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）