Green Energy & Environment
·
2021
·
IF 8.207
Ruichang Xue,Mengwei Guo,Zhuoming Wei,Qibo Zhang
Ni–Fe bimetallic electrodes are currently recognized as a kind of benchmark transition metal-based oxygen evolution reaction (OER) electrocatalysts. Facile synthesis of Ni–Fe bimetallic electrode materials with excellent catalytic activity and satisfied stability by a simple and low-cost route is still a big challenge. Herein, well-defined Ni–Fe nanoparticles in-situ developed on a planar Fe substrate (Ni–Fe NPs/Fe) is fabricated via a facile one-step galvanic replacement reaction (GRR) carried out in an Ethaline-based deep eutectic solvent (DES). The prepared Ni–Fe NPs/Fe exhibits outstanding OER performance, which needs an overpotential of only 319 mV to drive a current density of 10 mA cm −2 , with a small Tafel slope of 41.2 mV dec −1 in 1.0 mol L −1 KOH, high mass activity (up to 319.78 A g −1 at an overpotential of 300 mV) and robust durability for 200 h. Impressively, the Ni–Fe bimetallic oxygen-evolution electrode obtained from the Ethaline-based DES is catalytically more active and durable than that of its counterpart derived from the 4.2 mol L −1 NaCl aqueous solution. The reason for this is mainly related to the different morphology and surface state of the Ni–Fe catalysts obtained from these different solvent environments, particularly for the differences in phy–chemical properties, active species formed and deposition kinetics, offered by the Ethaline-based DES.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2023
·
IF 22.1
Lingxiang Huang,Yue Ma,Mufan Niu,Shenyong Ren,Qiaoxia Guo,Chunming Xu,Baojian Shen
Dry reforming reaction of greenhouse gas CH 4 and CO 2 was studied over Ni-Fe bimetallic catalyst, in which the composite support of C12A7-O 2- in MCM-41 was used. The isotope 13 CH 4 /D 2 O tracing experiment showed CO mainly comes from 13 CHx oxidation reaction and DH comes from CHx and D 2 O reaction, exhibiting lattice oxygen promotes CH X oxidation and water accelerate methane conversion. XPS and TPSR-MS studies exhibited the existence of lattice oxygen in catalysts produces a little H 2 O to facilitate a lower starting point at the reaction temperature. On-line MS investigation found that the trace water addition in the system accelerated the adsorption of CO 2 on support and promoted methane dissociation, the H 2 signal appears later than CO, indicating the oxidation reaction of CHx occurs after the dissociation of CO 2 . Besides, TG analysis tells us the H 2 O may consume Cα on the catalyst in time during the reaction process to remove carbon deposition.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 29
·15717-15723
·
IF 11.9
Jia-Wei Zhao,Kaihang Yue,Zi-Xiao Shi,Shu-Yin Wei,Wei-Qian Liang,Gao-Ren Li
In situ spectroscopic characterization has been considered as a key method to study catalytic mechanisms. However, most in situ spectroscopic characterizations can only be used to obtain the overall structure of the catalyst, and its spectral intensity depends on the average information about the catalyst as a whole or in a single area, which makes it difficult to determine the real active site of the catalyst. Herein, to overcome the limitations of traditional in situ spectroscopic characterizations, we developed in situ Raman mapping technology to achieve accurate characterizations of active sites during the oxygen evolution reaction (OER), and this work can directly identify and visualize the real active sites of Ni–Fe catalysts for the OER. The in situ Raman mapping technology clearly shows the surface reconstruction process and dynamic active site of the Ni–Fe catalyst during the OER, namely, Ni is converted to NiOOH and the formed NiOOH/Fe–NiOOH as an active site catalyzes the OER. The visualization of the dynamic active site developed in this paper will promote the understanding of the OER catalytic process and can be used in other homo/heterogeneous catalysis fields.
研究领域:
催化化学
·
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2017
·Vol. 11
·期 4
·613-623
·
IF 1.712
Tang Honggui,Li Shuangshuang,Gong Dandan,Guan Yi,Liu Yuan
Carbon deposition and sintering of active components such as nano particles are great challenges for Ni-based catalysts for CO methanation to generate synthetic natural gas from syngas. Facing the challenges, bimetallic catalysts with different Fe content derived from layered double hydroxide containing Ni, Fe, Mg, Al elements were prepared by co-precipitation method. Nanoparticles of Ni-Fe alloy were supported on mixed oxides of aluminium and magnesium after calcination and reduction. The catalysts were characterized by Brunner-Emmett-Teller (BET), X-ray diffraction, hydrogen temperature programmed reduction, inductively coupled plasma, X-ray photoelectron spectroscopy, transmission electron microscopy and thermogravimetric techniques, and their catalytic activity for CO methanation was investigated. The results show that the Ni-Fe alloy catalysts exhibit better catalytic performance than monometallic catalysts except for the Ni4Fe-red catalyst. The Ni2Fe-red catalyst shows the highest CO conversion (100% at 260–350 °C), as well as the highest CH 4 selectivity (over 95% at 280–350 °C), owing to the formation of Ni-Fe alloy. In stability test, the Ni2Fe-red catalyst exhibits great improvement in both anti-sintering and resistance to carbon formation compared with the Ni0Fe-red catalyst. The strong interaction between Ni and Fe element in alloy and surface distribution of Fe element not only inhibits the sintering of nanoparticles but restrains the formation of Ni clusters.
研究领域:
催化化学
·
材料科学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Fei Wang,Songyin Yu,Hui Xu,Junfeng Feng,Feihong Guo,Xiaoxiang Jiang,Jianchun Jiang
To solve the problem of harsh reaction conditions in lipid hydrogenation into fatty alcohol over Cu based bimetallic catalysts, the cheap Ni-base catalyst with high activity was synthesized. By using the hydrothermal method, the flower-like SiO 2 -ZrO 2 support was prepared. The Ni-Fe/SiO 2 -ZrO 2 catalyst was further prepared by the impregnation method and utilized in the fatty acid hydrogenation to produce fatty alcohol. Under the reaction conditions (240 °C, initial H 2 pressure: 2 MPa and reaction time: 3 h), the Ni-Fe/0.13SiO 2 -ZrO 2 catalyst attained 96.0% conversion and 86.4% fatty alcohol yield, much higher than that of Ni-Fe/ZrO 2 without SiO 2 (conversion 86.1% and fatty alcohol yield 61.9%). The high catalytic activity of Ni-Fe/0.13SiO 2 -ZrO 2 was ascribed to the increase of surface area, reduction of NiO grain size, and formation of flower-like morphology. The high selectivity to fatty alcohol over Ni-Fe/0.13SiO 2 -ZrO 2 was related to the increase of Lewis acidity (extra active sites) and the decrease of oxygen vacancy which weakened the adsorption of aldehyde (enol) on the catalyst and thus facilitated the formation of fatty alcohol.
研究领域:
催化化学
·
材料科学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2017
·
IF 4.601
Chuang Li,Guangyue Xu,Yongxiang Zhai,Xiaohao Liu,Yanfu Ma,Ying Zhang
Gamma-valerolactone (GVL) has been identified as a sustainable high-value platform molecular for the production of fuels and carbon-based chemicals. In this work, a series of activated carbon supported low-cost bimetallic Ni-Fe catalysts (Ni-Fe/AC) with different molar content of Fe species were prepared by using co-precipitation method for the liquid phase hydrogenation of ethyl levulinate (EL) to produce γ-valerolactone. The Ni-Fe 0.5 /AC exhibited the highest activity among the bimetallic or monometallic catalysts under mild reaction conditions (100 °C, 4 MPa H 2 , 6 h) and achieved 99.3% conversion of EL and 99.0% yield of GVL. Under more mild conditions (60 °C, 2 MPa H 2 ) and prolonging the reaction time to 24 h, EL could be converted completely and the obtained GVL yield was more than 98%. The catalysts were characterized by various techniques including XRD, TEM, HRTEM, EDX, XPS, H 2 -TPR and NH 3 -TPD. Based on the structure and activity relationship study, the formation of highly dispersed Ni-Fe alloy structure and the co-presented FeO x nanoparticles could be responsible for the high catalytic hydrogenation activity.
研究领域:
催化化学
·
可再生资源化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2025
·
IF 21.1
Zhanhong Zhao,He Zeng,Yi Zhou,Mingliang Yuan,Xinghua Chang
To address the inherent contradiction between adsorption/desorption energy barriers of intermediates in single-metal urea oxidation reaction (UOR) catalysts, this study developed a cyanide-bridged bimetallic catalyst , Ni 2 Fe(CN) 6 , via liquid-phase synthesis and plasma modification. Plasma modification enhances the structural stability of the three-dimensional framework and optimizes its electronic properties through selective metal ion substitution and framework reconstruction. In situ electrochemical Raman spectroscopy confirms that the cyanide bridge serves as an electron transport bridge, effectively linking Ni and Fe active centers and providing a stable electron transfer pathway for the Ni³ ⁺/Ni²⁺ redox cycle, leading to a 2.05-fold increase in cycling efficiency compared to untreated catalysts. Benefiting from the synergistic effect of the bimetallic centers, Ni 2 Fe(CN) 6 exhibits superior UOR electrocatalytic performance, achieving an overpotential of only 0.425 V（vs. Hg/HgO） at 10 mA cm −2 . Furthermore, theoretical calculations indicate that the protonation state of amino groups significantly influences the rate-determining step by modulating the reaction pathway. The presence of functionally distinct and diversified active sites enables a multi-pathway synergistic catalytic mechanism, effectively promoting key reaction steps, including amino proton transfer , C-N bond cleavage, and N-N coupling.
研究领域:
电催化
·
材料化学
·
能量转换
·
无机合成
·
理论化学
✓ 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）