CHEMICAL ENGINEERING SCIENCE
·
2024
·
IF 4.1
Bangjian Liu,Hong Yang,Huiqing Xu,Quanjie Liu,Shuandi Hou,Anfeng Zhang,Xinwen Guo
Effective regulation of acid sites is essential to strengthen the reaction performance and to modulate product distribution of an isomerization reaction. In this study, ZSM-50 (Al-EUO) and Fe-substituted ZSM-50 zeolites, namely FeAl-EUO-n (n = 0.25, 0.50 and 0.75) and Fe-EUO, are synthesized by a seed-assisted hydrothermal method. The study has shown that Fe has effectively entered the Al-EUO framework as a tetrahedrally-coordinated species. More importantly, the Fe-substitution has resulted in a significant increase in the amount of surface weak- and medium-strength Brönsted acids and a reduction in the strength of strong acids of FeAl-EUO-n. This study also evaluates the catalytic performance of Pt/FeAl-EUO-n catalysts in n-heptane hydroisomerization. It shows that the introduction of Fe in ZSM-50 greatly enhances the isomer yield, achieving a maximum yield of 66.1 % at 320 °C over Pt/FeAl-EUO-0.50 compared to 16.4 % at 300°C over Pt/Al-EUO. At the same time, the fraction of multi-branched iso -heptane also increases noticeably in the reaction product.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 34
·期 5
·2214904
·
IF 19
Jun Pan,Lulu Hu,Yuchen Zhang,Tao Zhang,Nana Wang,Shixue Dou,Hong Jin Fan
The development of polymer sodium batteries requires cathode materials with stable interfaces to avoid poor interfacial contact and interfacial side reactions during cycling. Here, a co-engineering strategy is deployed to tailor the cathode internal structure and improve the cathode interface stability through bonding interactions. Internally, the effect of low-cost Fe substitution in the obtained Na 0.67 Mn 2/3 Fe 1/3 O 2 cathode material renders favorable effects in several aspects. First, the increased lattice constant facilitates Na + intercalation and thereby lowers the diffusion barrier of Na + ions. Second, it increases the electronic conductivity, thereby improving the reaction reversibility. Third, the Mn O bond length is shortened, which alleviates the Jahn-Taylor effect and improves structural stability. In addition to these internal effects, the Fe O B bond interactions due to Fe substitution promote the decomposition of the tris(trimethylsilane)borate additive and the formation of a dense and uniform cathode electrolyte interface film, leading to improved cycling stability. Owing to the co-engineering of both internal structure and surface modification, the polymer solid-state sodium battery with a stable interface exhibits a specific capacity of 85.2 mAh g -1 after 800 cycles at 1 C.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2018
·
IF 3.141
Yujing Chen,Chuang Li,Xiao Chen,Yan Liu,Chi-Wing Tsang,Changhai Liang
A series of Fe-substituted ZSM-23 samples with different Fe/(Fe + Al) ratios were synthesized. Combined characterization by Fourier transform infrared spectroscopic, ESR, and X-ray photoelectron spectrosopic methods confirmed the presence of Fe in the ZSM-23 framework. The crystal size decreased with increasing Fe/(Fe + Al) ratio, and the Fe-substituted ZSM-23 samples exhibited large specific areas and pore volumes. The introduction of Fe in the framework reduced the acid strength compared with the Fe-free counterparts. Compared with the Pt/Fe-free ZSM-23 catalyst, the Pt/Fe-substituted catalysts showed lower activity to the hydroisomerization of n-hexadecane and higher isomerization selectivity. This is attributed to their higher ratios of weak and strong Brønsted acidic sites and smaller crystal size, which improved the product diffusion and suppressed the further product cracking. More 5M-C15 isomers were obtained over the Pt/Fe-substituted catalysts, which was different from the product distribution of Pt/Fe-free ZSM-23 where 2M-C15 isomers were the major isomer products.
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 JOURNAL
·
2025
·
IF 13.2
Zehua Wang,Ziyang Peng,Dan Li,Xinyi Liu,Qiong Mei,Jianfei Sun,Hongjie Wang
Thiamethoxam (THX), a neonicotinoid pesticide, exhibits potential ecotoxicity in aquatic environments. In this study, a combined experimental and density functional theory (DFT) approach was applied to investigate partial Fe-substituted Co 3 S 4 (Fe x Co, x = 0.01, 0.03, 0.05, 0.07, 0.09, and FeCo 2 S 4 ) for the effective activation of PMS and the degradation of THX. Fe doping elongated Co S bonds on the catalyst to promote the formation of sulfur vacancies, which enhance the adsorption and charge transfer capability of PMS. Due to the fastest degradation rate (0.511 min −1 ), the optimal PMS adsorption stability (1.11 eV), more electron transfer (0.72 e − ), and longer O O bond (1.468 Å), Fe 0.03 Co catalyst can preferably activate PMS to generate SO 4 •- and 1 O 2 , which was the most significant ROS for degrading THX. The initiation reaction of SO 4 •- -addition was superior to 1 O 2 , and the optimal active site was the C2 sites. Proposed degradation pathways and ecotoxicity evaluation highlighted the critical role of denitrification and hydroxylation in toxicity attenuation. In addition, Fe 0.03 Co/PMS catalyst had certain catalytic stability and reusability, and its degradation efficiency in farmland irrigation water can reach 80 %. This work not only elucidated the performance enhancement mechanism of Fe-substituted Co 3 S 4 catalyst, but also provided support for the application of sulfide-metals on advanced oxidation treatment of pesticide wastewater.
研究领域:
环境化学
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催化科学
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水污染控制
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理论计算化学
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农药环境行为
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高级氧化技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2025
·
IF 4.8
Ruxing Zhao,Qingrun Meng,Guanchao Wang,Lin Xu,Weifeng Chu,Junjie Li
Intermolecular dehydration of 2-propanol (IPA) to di-isopropyl ether (DIPE) serves as an important process to produce the valuable chemical, however, developing advanced solid acid catalysts with high DIPE selectivity faces the great challenge of inhibiting the intramolecular dehydration reaction. In this context, we developed a highly selective intermolecular dehydration MFI nanosheet catalyst by synergistically modifying its diffusion and acid properties. We found that the DIPE selectivity over nanosheet ZSM-5 catalysts were obviously higher than that over the conventional ZSM-5 catalyst, benefited from the enhanced diffusion property over nanosheet catalysts that inhibited the further conversion of DIPE. However, the DIPE selectivity were still lower than 70 % over those catalysts attributed to their high acid strength that facilitated the intramolecular dehydration reaction. Thus, various heteroatoms (Fe, Ga, and B) substituted MFI zeolite nanosheet catalysts were prepared and employed in the dehydration reaction, Fe-MFI with a moderate acid strength exhibited the highest DIPE selectivity among those catalysts. Besides, the effects of acid amounts (Si/Fe ratio) and diffusion properties (thickness of b-axis) on the intermolecular dehydration selectivity and activities over nanosheet Fe-MFI catalysts were systematically investigated. An optimal Fe-MFI nanosheet catalyst with the b-axis thickness of ∼20 nm and Si/Fe ratio of ∼40 presented the stable high DIPE selectivity of ∼91 % in 360 h of time on stream, meanwhile the IPA conversions kept almost unchanged.
研究领域:
催化
·
材料科学
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化学反应工程
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纳米技术
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2020
·Vol. 11
·期 1
·1-11
·
IF 12.121
Liu Wei,Li Jinxing,Li Wenting,Xu Hanying,Zhang Chao,Qiu Xinping
The low Coulombic efficiency during cycling hinders the application of Cobalt-free lithium-rich materials in lithium-ion batteries. Here we demonstrated that the dissolution of iron, rather than traditionally acknowledged manganese, is mainly responsible for the low Coulombic efficiency of the iron-substituted cobalt-free lithium-rich material. Besides, we presented an approach to inhibit the dissolution of transition metal ions by using concentrated electrolytes. We found that the cathode electrolyte interphase (CEI) layer formed in the concentrated electrolyte is a uniform and robust LiF-rich CEI, which is a sharp contrast with the uneven and fragile organic-rich CEI formed in the dilute electrolyte. The LiF-rich CEI not only effectively inhibits the dissolution of TMs but also stabilizes the cathode structure. The Coulombic efficiency, cycling stability, rate performance, and safety of the Fe-substituted cobalt-free lithium-rich cathode material in the concentrated electrolyte have been improved tremendously.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）