JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2025
·
IF 6.2
Yao Tong,Tianhua Yang,Jian Wang,Bingshuo Li,Haijun Zhang,Rundong Li
Hydrodeoxygenation (HDO) of lignin-derived phenolic compounds plays a crucial role in the production of renewable biofuels. In this regard, a series of different Co@NC catalysts were prepared with ZIF-67 as a sacrificial template by modulating the catalyst pyrolysis temperature and used for the catalytic hydrodeoxygenation of lignin-derived phenolic model compound 4-ethylphenol for the preparation of cyclohexanols/ cyclohexanes. The results showed that the low-temperature pyrolysis will retain a large number of CoO x compounds, which led to a high dispersion of Co. For Co@NC catalysts, the uniformly dispersed Co component facilitated the adsorption and transfer of hydrogen, and the exposed surface of the carrier promoted the adsorption of reactants. The pyrolysis temperature also played a crucial role in the differences in catalyst crystal surface, specific surface area, acid strength distribution and oxygen vacancies. Co@NC catalyst prepared at 600 °C has a stronger hydrogen absorption capacity, the largest specific surface area and a higher number of oxygen vacancies. Therefore, the Co@NC-600 catalyst showed the best HDO activity. Under the mild conditions (220 °C, 2.5 h and 3 MPa H 2 ), the conversion of 4-ethylphenol was close to 100 %, and the selectivities of 4-ethylcyclohexanol and ethylcyclohexane were 62.7 % and 10.8 %, respectively.
研究领域:
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
TRANSITION METAL CHEMISTRY
·
2025
·
IF 1.7
Wang Yuqin,He Lizi,Han Ning,Li Lishuang,Wang Meiyang
It is of great practical significance to explore and prepare cheap, high-performance, and stable catalysts for oxygen reduction reaction (ORR), but it is still in progress at present. Herein, a straightforward evaporation–pyrolysis strategy is designed for the preparation of 3D porous electrocatalysts (denoted as \(\textrm{Fe}-\textrm{Co}-\textrm{NC}\) , which represented carbonization products at °C) made of carbon nanoparticles combined with metallic Fe-Co-doped N-enriched bridged carbon nanotube by carbonization of a pristine ZIF8 as highly efficient and durable ORR electrocatalysts. The obtained Fe–Co–NC structure possesses 3D open porous texture, abundant active sites, desired nitrogen bonding type, and high specific surface area, providing them with excellent ORR activity. The optimal performing \(\textrm{Fe}-\textrm{Co}-\textrm{NC}\) catalyst presents an outstanding ORR performance in terms of a high onset potential ( \(\textrm{E}_{\text{ onset } }\) ) of 0.96 V (vs. RHE) and half-wave potential ( \(\textrm{E}_{1 / 2}\) ) of 0.86 V (vs. RHE), respectively, possible to rival those of the commercially available \(\textrm{Pt} / \textrm{C}\) in an alkaline electrolyte solution. Besides, the \(\textrm{Fe}-\textrm{Co}-\textrm{NC}\) catalyst manifests better stability than those of commercially available \(\textrm{Pt} / \textrm{C}\) , which is of importance for the optimization and characterization of novel electrocatalysts originated from non-precious metals.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2024
·
IF 3.9
Pengcheng Wang,Qingqing Jiang,XingYu Li,Xuedong Wang,Juncheng Hu
Generally, researchers focus on the regulation of metal sites rather than surrounding nonmetals in photothermal CO 2 hydrogenation reaction. Herein, concerning the role of non-metallic N species, a series of Co/NC-T catalysts have been fabricated via high-temperature pyrolysis of Zeolitic Imidazolate Frameworks-67. The CO 2 conversion rate shows a consistent tendency with the ratio of graphitized-N species while the product selectivity is closely related to the coordination state of Co-N x species. Co/NC-800 catalyst achieves high CO 2 conversion rate of 758 mmol g cat -1 h -1 with CH 4 selectivity of 99.6 %. After adding extra graphitized-N species, the CO 2 conversion rate could further enhance to 80.2 % for N-Co/NC-2. The role of N species in photothermal CO 2 hydrogenation reaction has been investigated in details, providing new insights for the design of metal organic frameworks derived metal/N-doped carbon catalysts.
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
AICHE JOURNAL
·
2024
·
IF 3.5
Le Zhou,Xin Zhang,Yu Han,Xin Li,Ze-Quan Zeng,Hai-Kui Zou,Yong Luo
The Co@NC catalyst exhibits significant protic solvent preference for hydrogenation of nitriles to primary amines. However, the effect of mixed protic solvents on catalytic hydrogenation has received little attention. Herein, the synergetic solvent effect has been proposed to accelerate the hydrogenation of adiponitrile (ADN) to hexamethylenediamine through H 2 O-ethanol hydrogen bond networks on Co@NC catalyst. Experimental screenings on solvents showed that ADN conversion in H 2 O-ethanol was 1.6 ~ 5.1 times greater than in single solvents. Kinetic models in H 2 O/ethanol ( v W = 0.6), H 2 O, and ethanol showed that the solvents effected on H 2 transformation dominated the reaction. Isotope labelling and kinetic experiments revealed that H 2 O and ethanol acted as co-catalysts through exchanging and transferring hydrogen via hydroxyl groups. Density functional theory calculations confirmed that the energy barrier for proton transfer mediated by H₂O–ethanol was reduced by 0.18 eV compared to proton transfer mediated by H₂O–H₂O dimers.
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
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Xin Zhang,Le Zhou,Yu Han,Zhi-Rong Fu,Yu-Wei Xiang,Bao-Ju Wang,Yong Luo
The synthesis of aminoaromatic sulfonic acid (ASA) compounds by catalytic hydrogenation of nitroaromatic sulfonic acid (NSA) compounds is a promising process due to its environmental friendliness. However, the catalysts for NSA hydrogenation have the problems of high cost and easy inactivation, which limited the industrial application of NSA hydrogenation. In this work, we successfully synthesized Co@NC-B-800 catalyst with sustainable development concept by using cheap bamboo leaves as raw material. The characterizations demonstrated that Co nanoparticles (NPs) coated by N-doped carbon and Co-N x species were the main active site. The hydrogenation of sodium m -nitrobenzenesulfonate (SNS) was used as a probe reaction to test the catalytic performance. The Co@NC-B-800 catalyst possesses high activity with SNS conversion of 99.63 % and the m -aminobenzene sulfonic acid selectivity of 99.74 % within 3.5 h at 100 ℃, 4 MPa. Furthermore, the hydrogenation of a series of NSA substrates catalyzed by Co@NC-B-800 catalyst also shows excellent performance.
研究领域:
催化化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2023
·
IF 6.2
Huaqi Wang,Chenghong Sun,Enze Zhu,Chaoyang Shi,Jie Yu,Mingli Xu
Metal–organic framework (MOF)-derived carbon materials have emerged as important candidates in the field of catalysis because of their simple synthesis, easy construction, good conductivity, and high catalytic activity. Fe 3 C nanoparticles prepared from MOFs facilitate the catalytic activity of adjacent single atoms and exhibit powerful catalytic properties. In this work, a composite structured catalyst with Fe 3 C, Co nanoparticles, and M-N x single atoms (M = Co, Fe) was synthesized (denoted as Fe 3 C-Co-NC) by constructing Fe-doped bilayer zeolitic imidazolate frameworks (ZIFs) with a core–shell structure, which were used as bifunctional catalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The Fe 3 C-Co-NC catalyst exhibits superior half-wave potential ( E 1/2 = 0.89 V) and overpotential ( E j=10 = 1.67 V) and outperforms the commercial Pt/C and RuO 2 . This result can be attributed to the high specific surface area, hierarchical pore structure , and high graphitization degree of the Fe 3 C-Co-NC catalyst, especially the synergistic effect between Fe 3 C and adjacent single-atom active sites. Specifically, the Zn–air battery assembled using the Fe 3 C-Co-NC catalyst displays high peak power density (203 mW cm −2 ) and specific capacity (815 mAh g −1 ) without degradation after charge/discharge cycles for 57 h. Therefore, this work offers important insights into the design and research of high-performance ORR/OER bifunctional catalysts.
研究领域:
催化材料
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 9
·090514
·
IF 4.316
Xiaochao Liu,Siyuan Peng,Xiaoxiao Li,Chao Liu,Jinming Zeng,Xiaopeng Qi,Tongxiang Liang
The development of low-cost, high catalytic activity oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts is the key to promoting the development of zinc-air batteries. In this paper, a simple one-step pyrolysis method was used to successfully synthesize a binary FeCo–Co/NC catalyst with FeCo and Co nanoparticles encapsulated in N-doped carbon nanotubes. This structure exhibits great characteristics: it has a variety of active species (FeCo, Co, NC), and there is close combination between these active species (FeCo, Co, NC). Electrochemical studies have shown that the initial potential of FeCo–Co/NC during ORR process is 0.93 V, the half-wave potential is 0.808 V, and the limiting current density is 4.94 mA cm−2. In the OER process, at an anode current density of 10 mA cm−2, an overpotential of only 353 mV is shown; a lower Tafel slope and good durability are also observed. Moreover, the zinc-air battery in preparation can be cycled for as long as 2000 times. This provides a new method for the preparation of high-efficiency dual-function electrocatalysts for OER and ORR.
研究领域:
材料科学
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电化学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
Science China-Materials
·
2022
·Vol. 66
·期 1
·169-178
·
IF 8.64
Wei Haisheng,Song Huaxing,Ren Yujing,Yan Xiaorui,Fang Geqian,Wang Wenhua,Ren Wanzhong,Zhu Mingyuan,Lin Jian
Metal-organic frameworks (MOFs) derived Co-based catalysts have received extensive attention in the chemoselective hydrogenation of nitroarenes, while they usually require a lot of solvent during the synthesis and identification of active species. This study explores a solid-phase synthesis strategy to obtain MOF precursors without using any solvent, which is then foamed and pyrolyzed to synthesize the Co@NC-X catalyst. It was found that a nitrogen-doped graphene shell can well encapsulate the Co nanoparticles. The resulting catalyst, which was pyrolyzed at 800°C, exhibited ~100% conversion for the hydrogenation of 3-nitrostyrene and >99% selectivity to 3-vinylaniline. This catalyst also showed excellent stability and good substrate universality for the hydrogenation of extensive substituted nitroarenes. Various characterizations revealed a positive relationship between the catalytic performance and the content of Co—N species tuned by pyrolysis temperature. This work provides a novel and green strategy to design an efficient Co-based catalyst for chemoselective hydrogenation.
研究领域:
催化
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材料科学
·
化工
·
绿色化学
✓ 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）