APPLIED CATALYSIS B-ENVIRONMENTAL
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2016
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IF 8.328
Xinyu Li,Di Li,Hao Tian,Liang Zeng,Zhi-Jian Zhao,Jinlong Gong
This paper describes the design of a Ni/La 2 O 3 catalyst using La 2 O 2 CO 3 nanorod as a support precursor (denoted as Ni/La 2 O 3 -LOC) via a wet impregnation method for dry reforming of methane (DRM). The results showed that La 2 O 3 derived from the La 2 O 2 CO 3 precursor maintained its initial morphology upon thermal treatment and could highly disperse Ni particles on it. Additionally, the nanorod-shaped support could provide more medium-strength basic sites to facilitate CO 2 adsorption and activation on its surface. Consequently, the Ni/La 2 O 3 -LOC catalyst reached 70% of CH 4 conversion and 75% of CO 2 conversion at 700 °C after 50 h DRM reaction with a H 2 /CO ratio of 0.87. The enhanced metal-support interaction restricted the sintering of nickel particles under harsh reaction conditions. Coke evolution on the catalysts was also investigated to understand coke formation mechanism and the role of La 2 O 2 CO 3 in coke elimination. It has been found that nickel dispersion can affect distribution of coke and La 2 O 2 CO 3 on the surface of catalyst, both of which have a close relation with catalytic performance.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
Petroleum Science
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2022
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IF 4.757
Wei-Long Zhan,Yu-Chao Lyu,Xin-Mei Liu,Lei Fan,Fu-Rang Li,Ye Yang
The Ni/SAPO-11 catalyst used for n-hexane hydroisomerization was prepared via a novel two-step crystallization strategy. It involves introduction of nickel salt into the pre-crystalized system of SAPO-11 by grinding followed by a second crystallization step. No extra solvent is introduced during the whole synthesis procedure which reduces waste liquid emissions significantly. More importantly, interaction between nickel and support is effectively regulated by the novel method to achieve a well dispersed nickel species and inhibit formation of inert nickel spinel simultaneously. Chemical environments of framework Si are tuned to enhance surface acidity of the Ni/SAPO-11 catalyst. It also shows smaller particle size which favors fast diffusion of reactants and products. Insights into the two-step crystallization indicate that accumulation of SAPO-11 precursors in the pre-crystallization stage, pH regulation by nickel salt and structural directing effect of Ni 2+ during the second crystallization period account for the rapid crystal growth and smaller particle size of the Ni/SAPO-11 catalyst. All the unique features endow the Ni/SAPO-11 catalyst higher activity and isomers selectivity than the Pt/SAPO-11 catalyst in n-hexane hydroisomerization.
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2024
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IF 4.7
Xiaofei Li,Lili Geng,Haifeng Shi,Songshou Ye,Ley Boon Sim,Jinbao Zheng,Nuowei Zhang,Binghui Chen
In this study, we utilized a sol-gel method to prepare Ni-HPW/SiO 2 catalysts with varying citric acid (CA):Ni molar ratios ranging from 0 to 5.0. The catalysts demonstrated different levels of activity in the hydrogenation of ethylbenzene , which correlated to their respective CA:Ni ratios. Introducing citric acid in the preparation process of nickel-based catalysts yielded mesopore formation and reduced NiO particle size, producing a more uniform NiO dispersion on SiO 2 , which was confirmed by BET, XRD, and TEM analyses. The results of H 2 -TPR, H 2 -TPD, NH 3 -TPD, and Py-IR analyses suggested that the addition of citric acid augmented the interaction between phosphotungstic acid (HPW), Ni species, and SiO 2 . Citric acid improved Ni species and HPW dispersion, fostering increased HPW-Ni species formation. This, in turn, generated additional electron-deficient Ni ions , stemming from semi-reduced HPW-Ni species, which acted as Lewis acid sites, enhancing Ni + species effectiveness in activating aromatic rings. The better-dispersed, non-HPW-bound NiO, which, upon complete reduction to Ni, led to a substantial rise in H 2 bond cleavage, thereby facilitating more hydrogen spillover. Overall, the infusion of citric acid into fabricating Ni-HPW/SiO 2 catalysts sparked a significant surge in their aromatic hydrogenation ability.
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
ENERGY & FUELS
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2023
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IF 5.3
Yixue Yang,Qiang Hu,Guimin Zhang,Xun Xie,Yuxin Liu,Liming Zhou,Kejing Wu,Houfang Lu,Bin Liang
Supported Ni on yttria stabilized zirconia (YSZ) is the most widely used anode for a solid oxide fuel cell (SOFC), where Ni particles are easy to agglomerate at a high temperature of 1400 °C and reductive hydrothermal environments. In this study, Ni particles are successfully dispersed on YSZ through strong interaction between Ni and SiO2. The thin and amorphous SiO2 films, grown by low-temperature chemical vapor deposition (CVD), become spherical particles of nickel silicates uniformly dispersed on the YSZ skeleton after sintering at 1400 °C. Also, the SiO2-anchored Ni particles supported on YSZ (Ni/YSZ-SiO2) are obtained via direct reduction. The electrochemical performance of the Ni/YSZ-SiO2 anode shows a higher power density of approximately 18% than an unmodified Ni/YSZ anode, which resulted from the longer effective TPB area assigned to the highly dispersed Ni particles. The microstructure containing SiO2-anchored Ni particles exhibits high stability under testing and reductive hydrothermal conditions. Accordingly, the method of growing a SiO2 layer via low-temperature CVD is considered as a probable route for the preparation of the Ni/YSZ electrode material with a well-defined microstructure.
研究领域:
材料科学
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能源工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2023
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IF 9.9
Shunfa Zhou,Guoli Zheng,Feng Ji,Jiatang Wang,Zhao Liu,Jiawei shi,Jing Li,Yang Hu,Chengwei Deng,Liyuan Fan,Weiwei Cai
Excellent porosity and accessibility are key requirements during carbon-based materials design for energy conversion applications. Herein, a Ni-based porous supramolecular framework with graphite-like morphology (Ni-SOF) was rationally designed as a carbon precursor. Ultrathin carbon nanosheets dispersed with Ni nanoparticles and Ni-N x sites (Ni@NiN x -N-C) were obtained via in-situ exfoliation during pyrolysis. Due to the hetero-porous structure succeeding from Ni-SOF, the Ni@NiN x -N-C catalyst showed outstanding bifunctional oxygen electrocatalytic activity with a narrow gap of 0.69 V between potential to deliver 10 mA cm −2 oxygen evolution and half-wave potential of oxygen reduction reaction, which even surpassed the Pt/C + IrO 2 pair. Therefore, the corresponding zinc-air battery exhibited excellent power output and stability. The multiple Ni-based active sites, the unique 2D structure with a high graphitization degree and large specific surface area synergistically contributed to the excellent bifunctional electrocatalytic activity of Ni@NiN x -N-C. This work provided a novel viewpoint for the development of carbon-based electrocatalyst.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）