APPLIED CATALYSIS B-ENVIRONMENTAL
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2021
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IF 19.503
Min Chen,Xubo Huang,Chen Chen,Wenqing Hou,Yiming Xu
Production of H 2 from water splitting is challenging. Herein, we report an increased production of H 2 on Zn 0.5 Cd 0.5 S (ZnCdS) in aqueous solution under a 420 nm LED lamp, via 4 wt % MCo 2 O 4 (M = Mg, Cr, Mn, Fe, Co, Ni, Cu, and Zn). Without addition of sacrifices, the rate of H 2 evolution ( R H , in a unit of mmol g ―1 h ―1 ) was 0.0154 for ZnCdS, and 0.057―0.551 for MCo 2 O 4 /ZnCdS. On addition of Na 2 S/Na 2 SO 3 , the corresponding R H increased to 18.5 and 31.5―78.2, respectively. In both cases, no H 2 was observed for MCo 2 O 4 . However, the R H obtained in presence of Na 2 S/Na 2 SO 3 had a negative correlation with M s and R 2 , respectively, where M s was the magnetization degree of MCo 2 O 4 , and R 2 was the charge transfer resistance for MCo 2 O 4 /ZnCdS at solid-liquid interface. Electrochemical measurement showed that MCo 2 O 4 /ZnCdS was more active than ZnCdS for proton reduction, water oxidation, and water(sulfide/sulfite) photo-oxidation, respectively. According to the solid photoluminescence, band parameters, and open circuit potentials, formation of a p-n junction is proposed, which facilitates the photoelectron transfer to ZnCdS for proton reduction, and the photohole transfer to MCo 2 O 4 for water (sulfide/sulfite) oxidation. It is also proposed that the magnetic field of MCo 2 O 4 inhibits the charge transfer between MCo 2 O 4 and ZnCdS. This work suggests that MCo 2 O 4 spinels are good co-catalysts, but their magnetization need to be minimized.
研究领域:
材料科学
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化学
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催化
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光化学
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DOI
高影响因子
CRYSTENGCOMM
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2021
·Vol. 23
·期 25
·4522-4533
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IF 3.545
Jingjing Wang,Suhang Chen,Qiufan Tang,Jizhen Li,Kangzhen Xu
One of the challenges in solid propellant formulation is the ability to extend the combustion performance by efficiently catalyzing the decomposition of energetic additives. Herein, a series of cobalt acid composites nano-MCo2O4 (M = Cu, Ni, Zn, Mg, Fe, Ba) with homogeneous morphology and small particle size were systematically prepared by a solvothermal method. The crystal structure, surface morphology and catalytic performance of MCo2O4 were adjusted by the special co-solvent isopropanol and glycerol, exhibiting a regular and uniform spherical structure with an average diameter of 900 nm. The surface of MCo2O4 before calcination is wrapped with a layer of a fold-like substance, which is related to the addition of glycerol. XRD results show that BaCo2O4 was firstly prepared by this method in this study. Finally, the catalytic decomposition performance of MCo2O4 composites toward ammonium perchlorate (AP) and cyclotrimethylenetrinitramine (RDX) was investigated and compared via the DSC method. BaCo2O4 and CuCo2O4 exhibit the best catalytic activity toward AP and RDX, respectively, which is mainly due to their higher crystallinity and the better catalytic activity of copper ions. The simple and high-yield pathway for obtaining nano-MCo2O4 in this work provides a new insight to design and develop a kind of high-performance combustion catalyst for solid propellants.
研究领域:
材料科学
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推进剂化学
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产品关联
DOI
高影响因子
FUEL
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2022
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IF 8.035
Kaige Li,Tao Li,Yuhang Dai,Yanhong Quan,Jinxian Zhao,Jun Ren
MCo 2 O 4 (M = Co, Cu, Ni or Zn) spinel catalysts have been prepared using a chemical co-precipitation method and applied in toluene combustion. The physicochemical properties of the MCo 2 O 4 catalysts was discussed to explore the impact of substitution on the tetrahedral A-site ions. The results of the activity evaluation show that the catalytic performances of Co 3 O 4 , CuCo 2 O 4 and NiCo 2 O 4 with urchin-like morphology are far superior than ZnCo 2 O 4 nanoparticles. The CuCo 2 O 4 catalyst exhibited the most superior performance for toluene combustion, and the toluene conversion rate reached 90% at 230 °C. When compared to the other catalysts, the optimal activity of CuCo 2 O 4 was attributed to the presence of more reactive oxygen species, a higher concentration of Co 3+ ions on catalyst surface and better reducibility at relative lower temperature. Moreover, the catalytic activity of the CuCo 2 O 4 catalyst did not decrease significantly in the long-term test, demonstrating its excellent stability.
研究领域:
材料化学
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环境催化
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纳米材料
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能源与环境科学
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表面化学
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DOI
高影响因子
Surfaces and Interfaces
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2026
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IF 6
Jiayuan Zhang,Zhenlong Liu,Yu Liu,Liping Jiang,Caixia Ma,Lei Yang,Zunyuan Xie,Jizhen Li,Guofang Zhang
Transition metal oxides exhibit inherent catalytic activity for ammonium perchlorate (AP) decomposition; however, their performance is limited by the scarcity of accessible active sites and low conductivity. Therefore, morphology-directed structural design and interfacial engineering are highly desirable. In this study, two-dimensional (2D) MCo 2 O 4 nanosheets ( M = Fe, Ni, Cu, and Cr) were synthesized via a thermal expansion method and subsequently combined with three types of carbon materials C x (C x = rGO, CNTs, and g-C 3 N 4 ) to construct 2D MCo 2 O 4 /C x composites. Structural analyses demonstrate that the intimate interfacial coupling between 2D MCo 2 O 4 nanosheets and carbon materials effectively suppresses restacking and establishes a continuous conductive network. More importantly, strong interfacial coupling enables effective electronic modulation at the heterojunction, resulting in an optimized charge distribution and enhanced interfacial electron transfer. Among all catalysts, 5 wt. % FeCo 2 O 4 /rGO-1 demonstrates the most notable catalytic activity for AP decomposition, reducing its peak temperature in the high-temperature decomposition stage by 137.4 °C and increasing its heat release by 736.33 J·g⁻ 1 . Electrochemical tests confirm that accelerated interfacial charge transfer enhances AP pyrolysis. Kinetic modelling, TG-FTIR-MS, and DFT calculations indicate that the 2D-2D heterointerface boosts the adsorption of the AP intermediate NH 3 and promotes its conversion into higher-valence NO 2 , while also accelerating electron transport and lowering the decomposition barrier. The synergistic effect between interfacial electron transport and the heterojunction promotes the rapid AP degradation. Based on these findings, a plausible catalytic mechanism for AP decomposition is proposed.
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
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2026
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IF 6.6
Nguyen Ngoc Huyen,Ngo Xuan Dinh,Pham Thi Tuyet Nhung,Ong Van Hoang,Tran Van Tan,Nguyen Duc Toan,De Pham-Cong,Pham Duc Thang,Anh-Tuan Le
Tunable cation distribution in spinel MCo2O4 enhances surface redox activity. • Microwave-assisted hydrothermal yields ZCO nanosheets and CCO nanorods with defects. • Oxygen vacancies and mixed cations boost interfacial charge transfer kinetics. • CCO/SPE shows high sensitivity and low LOD for Carbendazim detection. • Strong Carbendazim adsorption on spinel surfaces confirmed by experiment and theory. Spinel cobaltites MCo 2 O 4 (M is a divalent metal ion) nanomaterials have emerged as promising electrocatalysts for electrochemical sensing owing to their tunable cation distribution and redox-active metal centers. In this work, ZnCo 2 O 4 (ZCO) nanosheets and CuCo 2 O 4 (CCO) nanorods were prepared using a simple microwave-assisted hydrothermal method and subsequently employed to modify screen-printed electrodes (SPEs) for carbendazim (CBZ) detection. Structural analysis revealed distinct cation arrangements within the spinel lattice, particularly CCO exhibited mixed Cu/Co occupancy and abundant oxygen vacancies. Both modified electrodes significantly enhanced the electrochemical oxidation of CBZ compared with bare SPE, primarily due to the catalytic activity of the Co 3+ /Co 2+ redox couple. Notably, the CCO/SPE demonstrated superior sensing performance, arising from the synergistic effects of Cu 2+ /Cu + redox activity, high defect density, and one-dimensional morphology that promoted charge transfer and mass diffusion. The CCO/SPE sensor delivered promising analytical performance, featuring two linear ranges (0.1–10 and 10–500 µM), a detection limit of 0.07 µM, and a sensitivity of 5.97 µA µM −1 cm −2 . Combined experimental and theoretical analyses suggest strong CBZ adsorption on the MCo 2 O 4 spinel surface, highlighting spinel oxides as efficient electrocatalysts for CBZ pesticide sensing. Download: Download high-res image (241KB) Download: Download full-size image
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高影响因子
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