Catalysts
·
2015
·Vol. 5
·期 2
·606-633
·
IF 2
Hongmei Qin,Xiaoshuang Qian,Tao Meng,Yi Lin,Zhen Ma
Conventional supported Pt catalysts have often been prepared by loading Pt onto commercial supports, such as SiO2, TiO2, Al2O3, and carbon. These catalysts usually have simple metal-support (i.e., Pt-SiO2) interfaces. To tune the catalytic performance of supported Pt catalysts, it is desirable to modify the metal-support interfaces by incorporating an oxide additive into the catalyst formula. Here we prepared three series of metal oxide-modified Pt catalysts (i.e., Pt/MOx/SiO2, Pt/MOx/TiO2, and Pt/MOx/Al2O3, where M = Al, Fe, Co, Cu, Zn, Ba, La) for CO oxidation. Among them, Pt/CoOx/SiO2, Pt/CoOx/TiO2, and Pt/CoOx/Al2O3showed the highest catalytic activities. Relevant samples were characterized by N2adsorption-desorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), H2temperature-programmed reduction (H2-TPR), X-ray photoelectron spectroscopy (XPS), CO temperature-programmed desorption (CO-TPD), O2temperature-programmed desorption (O2-TPD), and CO2temperature-programmed desorption (CO2-TPD).Keywords:Pt catalysts;cobalt oxide;CO oxidation
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
·
2020
·
IF 10.652
Lei Huang,Min Wei,Shahid Zaman,Asad Ali,Bao Yu Xia
Integrating the merits of various catalytic materials into one novel hybrid is significant yet challenging in developing multifunctional electrode for overall water splitting. In this work, micro-platinum modification strategy is developed to construct the bifunctional Pt@Co 3 O 4 /Ni foam (NF) hybrid electrode for overall water splitting. The resultant Pt@Co 3 O 4 /NF electrode exhibits low overpotentials and favorable kinetics for both hydrogen (30 mV@10 mA cm −2 , 31 mV dec −1 ) and oxygen evolution (263 mV@10 mA cm −2 , 69 mV dec −1 ). Moreover, a voltage of ~ 1.53 V can drive a current density of 10 mA cm −2 for the two-electrode electrolyzer. The enhanced performance of Pt@Co 3 O 4 /NF hybrid could be attributed to the synergistic effect of micro-Pt modified Co 3 O 4 nanorod array with the optimized water cleavage and hydrogen recombination. This work not only reports an efficient hybrid electrode for overall water splitting but also offers valuable insights in designing multifunctional electrocatalysts for energy conversion technologies.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2017
·
IF 2.986
Shuaishuai Lu,Jingde Zhang,Yuanyuan Sun,Huichao Liu
CuO-CeO 2 -ZrO 2 /cordierite catalysts have been successfully prepared by the impregnation reduction method. The effects of processing parameters such as the condition of reduction process, calcination temperature, the addition of surfactant on the size and shape of catalyst particles were studied by X-ray diffraction (XRD), BET surface area measurements, and scanning electron microscopy (SEM). The catalytic performance of the as-prepared catalysts for CO oxidation were evaluated by using a microreactor-GC system. The results indicate that the processing parameters influence greatly the size and shape of catalyst particles. Fragmental shape catalysts were formed when the impregnated samples were reduced in the thermostat water bath. However, spherical-like particles were obtained by ultrasonic-assisted in the reduction process. Tiny flower-like catalyst particles were found when the surfactant were used. When the calcination temperature decreased, the grain size of catalysts has reduced, and the catalytic activity for CO oxidation has been improved. The introduction of ultrasonic and surfactant resulted in larger specific surface area and better catalytic performance.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Keke Yang,Guilin Song,Yuanyuan Li,Qingda An,Shangru Zhai,Zuoyi Xiao
Nowadays there is much room for improvement in the designed synthesis of high-performance electromagnetic wave absorbers by combining metal-organic frameworks (MOFs) and biomass components. Herein, 3D N-doped porous carbon cobalt/cobalt oxide (NPC/Co/CoO) composites were successfully prepared by transforming in-situ grown ZIF-67 clusters on a chitosan matrix. Analysis results showed that the N-doped carbonaceous composites obtained had unique porosity, high specific surface area, and defect-enriched structure, which provided numerous paths for electron transfer , leading to big benefits to interfacial polarization and dipole polarization. Most importantly, the ferromagnetic resonance and magnetic coupling were enhanced by ZIF-67-derived Co/CoO nanoparticles . By adjusting the content of metallic cobalt salt, pyrolysis temperature, and sample filling content, the optimal impedance matching properties of the composites could be optimized. When the matching thickness is 2 mm, the RL min of NPC/Co/CoO-10/700–30 wt% achieved − 48.97 dB at 13.52 GHz, and the effective absorption bandwidth exceeds 5.36 GHz. The composites with excellent performance prepared by a controllable process using chitosan and ZIF-67 might be a promising alternative for the large-scale preparation of high-frequency electromagnetic wave absorbers.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
·
2019
·
IF 3.834
Shenhao Yuan,Xushuai Lv,Yiwei Zhang,Yangjin Wu,Chunfeng Mao,Yuming Zhou,Wenxia Chen,Yanyun Wang
A core-shell structure Au-based catalysts mSiO 2 /Au/Co 3 O 4 HS were successfully derived from in-situ growth ZIF-67 hollow spheres, which were synthesized by a one-step soft template method. The samples were characterized by SEM, TEM, EDX, XPS, XRD and BET to confirm its successful preparation and structural features. The catalytic performance of the catalysts were evaluated by liquid phase oxidation of benzyl alcohol to benzaldehyde with O 2 as the oxidant under alkaline conditions. The experimental results illustrated that reaction conditions, including effect of catalyst amount, oxygen flow rate, reaction temperature and reaction time, were optimized to be 40 mg, 50 ml/min, 140 °C and 5 h, respectively. Meanwhile, 55% conversion of benzyl alcohol and 84% selectivitiy to benzaldehyde together with the excellent reusability and stability were achieved under optimal reaction conditions, which was attributed to the core-shell structure leading to the encapsulation of Au NPs and provision of multiple active reaction interface. Based on the intermediates formed from the de-protonation of substrate, a plausible oxidation reaction mechanism with mSiO 2 /Au/Co 3 O 4 HS catalysts was tentatively proposed to study the relationship between structure and catalytic performance.
研究领域:
材料科学
·
催化化学
✓ 已验证
DOI
高影响因子
Applied Sciences-Basel
·
2022
·Vol. 12
·期 8
·3769
·
IF 2.838
Wei Ma,Dong Ye,Haining Wang
Herein, a series of Co-Fe mixed oxide modified ZSM-5 adsorbents were synthesized using the ultrasonic-assisted impregnation method for the capture of elemental mercury. In comparison with other samples, Co4Fe1-ZSM-5 produced a relatively better performance, with the removal efficiency of around 96.6% Hg0and the adsorption capacity of around 901.63 ug/mg Hg0achieved at 120 °C. The interaction between CoOxand FeOximproved the reducibility of oxygen species, thus promoting the oxidation of Hg0. Among a variety of other gas components, O2and NO exerted a positive effect on Hg0, which improved its removal to a certain extent. By contrast, SO2caused an adverse effect on the capture of Hg0, which could be reversed to some degree by the introduction of 5% O2. After five cycles, the mercury removal efficiency of Co4Fe1-ZSM-5 remained above 90%, suggesting excellent recyclability. Finally, XPS analysis was conducted to reveal that Mars–Maessen mechanisms are dominant in the process of mercury adsorption.Keywords:Hg0adsorption;ZSM-5;cobalt oxide;iron oxide;regeneration
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
Catalysts
·
2023
·Vol. 13
·期 5
·828
·
IF 3.9
Ye Zhu,Xue-Wen Zhang,Fei Wang,Bing Xue,Jie Xu
Mesoporous carbon nitride (mpg-C3N4) was prepared by using cyanamide as a precursor and colloidal nanosilica as a template. Then, the mpg-C3N4was used as a catalytic support to load CoOx. The physicochemical properties of the synthesized CoOx/mpg-C3N4materials were elucidated by multiple characterization methods, and the catalytic activities were examined in the selective oxidation of ethylbenzene (EB) under atmospheric pressure by usingtert-butyl hydrogen peroxide (TBHP) as an oxidant. It was found that mpg-C3N4possessed a higher specific surface area than other carbon nitride materials, and its abundant Nbspecies were able to interact with Co (II) species. When the dosages of EB and TBHP were 10 mmol and 30 mmol, respectively, the reaction temperature was 100 °C, and the reaction time was 10 h, the conversion rate of ethylbenzene was 62%, and the selectivity of AP was 84.7%.Keywords:carbon nitride (C3N4);mesoporous material;cobalt oxide;selective oxidation;ethylbenzene
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
Journal of Energy Chemistry
·
2019
·
IF 5.162
Han Wu,Min Wu,Boyang Wang,Xue Yong,Yushan Liu,Baojun Li,Baozhong Liu,Siyu Lu
Ammonia borane (AB) is an excellent candidate for the chemical storage of hydrogen. However, its practical utilization for hydrogen production is hindered by the need for expensive noble-metal-based catalysts. Herein, we report Co–Co 3 O 4 nanoparticles (NPs) facilely deposited on carbon dots (CDs) as a highly efficient, robust, and noble-metal-free catalyst for the hydrolysis of AB. The incorporation of the multi-interfaces between Co, Co 3 O 4 NPs, and CDs endows this hybrid material with excellent catalytic activity ( r B = 6816 m L H 2 min –1 g Co –1 ) exceeding that of previous non-noble-metal NP systems and even that of some noble-metal NP systems. A further mechanistic study suggests that these interfacial interactions can affect the electronic structures of interfacial atoms and provide abundant adsorption sites for AB and water molecules, resulting in a low energy barrier for the activation of reactive molecules and thus substantial improvement of the catalytic rate.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Bachirou Guene Lougou,Boxi Geng,Boshu Jiang,Hao Zhang,Qiming Sun,Yong Shuai,Zhibin Qu,Jiupeng Zhao,Chi-Hwa Wang
CO 2 -splitting and thermochemical energy conversion effectiveness are still challenged by the selectivity of metal/metal oxide-based redox materials and associated chemical reaction constraints. This study proposed an interface/substrate engineering approach for improving CO 2 -splitting and thermochemical energy conversion through CuFe 2 O 4 and Co 3 O 4 two-layer coating SiC. The newly prepared material reactive surface area available for gas–solid reactions is characterized by micro-pores CuFe 2 O 4 alloy easing inter-layer oxygen micro mass exchanges across a highly stable SiC-Co 3 O 4 layer. Through a thermogravimetry analysis, oxidation of the thermally activated oxygen carriers exhibited remarkably CO 2 -splitting capacities with a total CO yield of 1919.33 µmol/g at 1300 °C. The further analysis of the material CO 2 -splitting performance at the reactor scale resulted in 919.04 mL (788.94 µmol/g) of CO yield with an instantaneous CO production rate of 22.52 mL/min and chemical energy density of 223.37 kJ/kg at 1000 °C isothermal redox cycles. The reaction kinetic behavior indicated activation energy of 30.65 kJ/mol, which suggested faster CO 2 activation and oxidation kinetic on SiC-Co 3 O 4 -CuFe 2 O 4 O-deficit surfaces. The underlying mechanism for the remarkable thermochemical performances was analyzed by combining experiment and density functional theory (DFT) calculations. The significance of exploiting the synergy between CuFe 2 O 4 and Co 3 O 4 layers and stoichiometric reaction characteristics provided fundamental insights useful for the theoretical modeling and practical application of the solar thermochemical process.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Wenlong Liu,Jianzong Man,Xiaodong Sun,Weijia Liu,Yehong Du,Qian Wang,Zhongsheng Wen,Song Li,Juncai Sun
lithium (Li) metal has emerged as one of the most promising anode materials for next-generation batteries, attracting considerable interest owing to its exceptional high energy density and specific capacity. However, severe volume expansion and dendritic growth during cycling critically hinder the practical application of Li metal anodes. Herein, a hollow carbon sphere-encapsulating cobalt oxide (CoO) core (CoO/CS) framework was fabricated through a layer-by-layer assembly and controlled etching approach, which effectively suppresses dendrite formation in Li metal anodes. Density functional theory (DFT) calculations reveal that the CoO core exhibits significantly higher Li adsorption energy compared to the graphite shell, demonstrating its preferential role in guiding Li deposition. COMSOL Multiphysics simulations demonstrate that the CoO core effectively optimizes the local current density distribution. Consequently, the Li + preferentially nucleates at the CoO core due to its lithiophilic character, sequentially filling the hollow carbon sphere's interior volume. The hollow architecture provides abundant nucleation sites and sufficient void space to accommodate deposited Li metal, effectively mitigating volume changes during cycling. The synergistic combination of the hollow carbon structure and lithiophilic CoO core enables exceptional stability (operation exceeding 1700 h). Finally, the full cell capacity of CoO/CS electrode shows significant improvement across various current densities.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2020
·
IF 3.594
Ziyin Yang,Xiao Bai
This paper reports the synthesis of S-doped thin Co 3 O 4 shell with Au flower as core for nonenzymatic glucose sensing, where Au@Co 3 O 4 was obtained through assembly process triggered by redox reaction of Co 2+ and Au 3+ , and then S was doped into Co 3 O 4 shell via a hydrothermal process. The morphology, composition and structure of Au@Co 3 O 4 -S were characterized by transmission electron microscopy and X-ray diffraction, which showed that the core–shell structure was composed with Au core flower and S-doped thin Co 3 O 4 shell. Electrochemical property of Au@Co 3 O 4 -S toward glucose was explored, and an excellent electrocatalytic performance with a wide linear range of 0.2 μM–3.1 mM, a high sensitivity of 1127.3 μA mM −1 cm −2 and a low detection limit of 0.09 μM (S/N = 3) was obtained, which may be due to that the low conductivity of Co 3 O 4 was mitigated by conductive Au core flower and S doping, therefore making thin Co 3 O 4 shell provide more effective active sites for glucose reaction. Considering such excellent results, Au@Co 3 O 4 -S was proven as a promising material for electrochemical sensing of glucose.
研究领域:
材料科学
·
电化学
·
生物传感
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Zhe Li,Chun-yong Zhang,Hao-yu Wang,Lin Zhu,Hai-tao Liu,Li Shu,Ying-pin Weng
Herein, a simple hydrothermal method was used to synthesize cobalt hydroxide/nickel sulfide and cobalt foam (Co(OH) 2 /NiS@CF) composite electrode. By simply heating cobalt foam in the aqueous solution containing cobalt nitrate, nickel nitrate, and thiourea, Co(OH) 2 /NiS nano stereoscopic website was synthesized on Cobalt foam. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and electrochemical tests were used to characterize these composite electrodes. When the molar ratio of Co(NO 3 ) 2 ·6H 2 O to Thiourea of 4:5, Co(OH) 2 /NiS@CF exhibits excellent performance under these tests. The specific capacitance was 1260 F/g at 1.0 A/g. The composite electrode had 92.3% capacitance retention after 2000 charge-discharge cycles at 1.0 A/g.
研究领域:
材料科学
·
电化学
✓ 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）