INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2025
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IF 8.3
Jingwei Du,Jinjun Li,Zhixiong You
This study explores the preparation of a Cs-doped Ru/ZrO 2 catalyst using a low eutectic system and its application in ammonia synthesis. Additionally, it examines the effect of Cs doping on enhancing the catalyst's resistance to hydrogen poisoning. Compared to the undoped Ru/ZrO 2 catalyst and the Cs–Ru/ZrO 2 –B catalyst prepared through the grinding method for promoter incorporation, the Cs–Ru/ZrO 2 -A catalyst synthesized using the low eutectic system demonstrated significantly enhanced activity. At 400 °C and 0.1 MPa, the Cs–Ru/ZrO 2 -A catalyst achieved an ammonia synthesis activity of 1769 μmol g cat −1 h −1 , which is approximately 35 times higher than that of the undoped Ru/ZrO 2 catalyst. The structure of the catalyst was analyzed using various material characterization techniques, including XRD, XPS, and SEM. The results showed that the Cs–Ru/ZrO 2 -A catalyst, prepared under identical conditions, exhibited no significant structural differences compared to other catalysts. However, further TPR and TPD analyses revealed that Cs interacts with Ru to some extent, affecting its reduction behavior and enhancing the catalytic reaction rate for ammonia synthesis. Additionally, detailed XPS analysis of all catalysts was conducted, leading to a proposed relationship between the catalytic reaction rate and the oxidation states of the metal components. The study revealed that the presence of Cs significantly inhibits hydrogen poisoning of the catalyst. Furthermore, it demonstrated that the addition of promoters enhances H 2 dissociation by supplying electrons to the active metal Ru, while Cs plays a crucial role in effectively suppressing hydrogen poisoning.
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
Catalysis Science & Technology
·
2023
·Vol. 13
·期 14
·4156-4167
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IF 5
Ji Feng,Lin Liu,Xiaohua Ju,Qike Jiang,Jiemin Wang,Jianping Guo,Teng He,Ping Chen
Utilization of promoters to improve the catalytic performance of supported metal catalysts is an important strategy for the design of efficient catalysts. However, it is difficult to detect the relationship between the promoters and the structure of main catalysts. Herein, we firstly develop an efficient Ru-based ammonia synthesis catalyst by decorating Ru nanoparticles (NPs) on γ-alumina with sub-nanometer ceria (CeO2) species (Ce–Ru/Al2O3). In comparison with neat Ru/Al2O3, Ce–Ru/Al2O3 exhibits up to 10-fold activity enhancement at 400 °C and 1.0 MPa. Our characterization results show that such an activity increment is relevant to the function of the sub-nanometer CeO2 species on the Ru NPs. The sub-nanometer CeO2 species will aggregate around the Ru nanoparticles, leading to a clear electron transfer from sub-nanometer CeO2 species to Ru nanoparticles. At the same time, the introduction of CeO2 species can not only weaken the hydrogen poisoning effect on the Ru nanoparticles but also facilitate nitrogen adsorption and hydrogenation of dissociated N* atoms according to the kinetic test results. This work highlights the important role of highly dispersed rare earth oxide promoter species in modulating the structure and catalytic performance of supported Ru NPs for ammonia synthesis.
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
Small
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2024
·Vol. 20
·期 32
·2311840
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IF 13
Xinhua Zhao,Lingling Du,Xiaxia Xing,Zhenxu Li,Yingying Tian,Xiaoyu Chen,Xiaoyan Lang,Huigang Liu,Dachi Yang
With the recently-booming hydrogen (H 2 ) economy by green H 2 as the energy carriers and the newly-emerged exhaled diagnosis by human organ-metabolized H 2 as a biomarker, H 2 sensing is simultaneously required with fast response, low detection limit, and tolerant stability against humidity, switching, and poisoning. Here, reliable H 2 sensing has been developed by utilizing indium oxide nanocubes decorated with palladium and gold nanodots (Pd–Au NDs/In 2 O 3 NCBs), which have been synthesized by combined hydrothermal reaction, annealing, and chemical bath deposition. As-prepared Pd–Au NDs/In 2 O 3 NCBs are observed with surface-enriched NDs and nanopores. Beneficially, Pd–Au NDs/In 2 O 3 NCBs show 300 ppb-low detection limit, 5 s-fast response to 500 ppm H 2 , 75%RH-high humidity tolerance, and 56 days-long stability at 280 °C. Further, Pd–Au NDs/In 2 O 3 NCBs show excellent stability against switching sensing response, and are tolerant to H 2 S poisoning even being exposed to 10 ppm H 2 S at 280 °C. Such excellent H 2 sensing may be attributed to the synergistic effect of the boosted Pd–Au NDs’ spillover effect and interfacial electron transfer, increased adsorption sites over the porous NCBs’ surface, and utilized Pd NDs’ affinity with H 2 and H 2 S. Practically, Pd–Au NDs/In 2 O 3 NCBs are integrated into the H 2 sensing device, which can reliably communicate with a smartphone.
研究领域:
材料科学
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传感器技术
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纳米技术
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DOI
高影响因子
Nature Chemistry
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2024
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IF 19.2
Zhang Yangyu,Peng Xuanbei,Tian Han-Rui,Yang Bo,Chen Zuo-Chang,Li Jiejie,Zhang Tianhua,Zhang Mingyuan,Liang Xiaocong,Yu Zhiyang,Zhou Yanliang,Zheng Lirong,Wang Xiuyun,Zheng Jian-Wei,Tang Yu,Au Chak-tong,Jiang Lilong,Xie Su-Yuan
Developing highly effective catalysts for ammonia (NH 3 ) synthesis is a challenging task. Even the current, prevalent iron-derived catalysts used for industrial NH 3 synthesis require harsh reaction conditions and involve massive energy consumption. Here we show that anchoring buckminsterfullerene (C 60 ) onto non-iron transition metals yields cluster-matrix co-catalysts that are highly efficient for NH 3 synthesis. Such co-catalysts feature separate catalytic active sites for hydrogen and nitrogen. The ‘electron buffer’ behaviour of C 60 balances the electron density at catalytic transition metal sites and enables the synergistic activation of nitrogen on transition metals in addition to the activation and migration of hydrogen on C 60 sites. As demonstrated in long-term, continuous runs, the C 60 -promoting transition metal co-catalysts exhibit higher NH 3 synthesis rates than catalysts without C 60 . With the involvement of C 60 , the rate-determining step in the cluster-matrix co-catalysis is found to be the hydrogenation of *NH 2 . C 60 incorporation exemplifies a practical approach for solving hydrogen poisoning on a wide variety of oxide-supported Ru catalysts.
研究领域:
化学
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材料科学
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催化
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氨生产
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
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2024
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IF 4.1
Xuanbei Peng,Yongjin Luo,Tianhua Zhang,Jinxiu Deng,Yanliang Zhou,Jiaxin Li,Jun Ni,Bingyu Lin,Jianxin Lin,Dongshuang Wu,Lirong Zheng,Xiuyun Wang,Lilong Jiang
The effects of promoters on Ru nanoparticles (≥2 nm) catalysts for NH 3 synthesis have been extensively elaborated, but their roles on ultrasmall Ru nanoclusters (NCs, 1–2 nm) remain largely unknown and need to be further uncovered. Herein, a series of K-promoted MgO supported Ru NCs were synthesized and investigated for NH 3 synthesis. The addition of 5wt.%K onto Ru/MgO NCs leads to a significantly high NH 3 synthesis rate of 21.7 mmol NH3 g cat −1 h −1 at 400 °C and 0.2 MPa, close to the thermodynamic equilibrium. Out studies reveal that anchoring K onto Ru NCs can increase the electron density and cause an upshift of the d -band center of Ru entities. Moreover, the addition of K regulates the hydrogen affinity and accelerates the migration of hydrogen from the Ru NCs surface to MgO support, which is crucial in avoiding the hydrogen poisoning effect on Ru NCs. With the synergistic effect of the Ru NCs sites bridged by H-spillover, makes the K-mediated Ru/MgO NCs catalysts efficient for NH 3 synthesis at mild conditions.
研究领域:
催化
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材料科学
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化学工程
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物理化学
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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）