JOURNAL OF ELECTROANALYTICAL CHEMISTRY
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2023
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IF 4.5
Yanli Zhang,Jiuqing Xiong,Shihai Yan,Bingping Liu
Electrochemical reduction of nitrate to NH 3 is a very promising alternative reaction to the Haber-Bosch process, and it is necessary to develop the efficient electrocatalysts. In this study, a particle-support mode Co 3 O 4 catalyst was synthesized with ZIF-67 as the precursor, and then dispersed on MoS 2 nanoflowers by hydrothermal method. The Co 3 O 4 is anchored to MoS 2 by forming Co-S coordination bond. Furthermore, the particle-supported Co 3 O 4 exhibits better performance than Co 3 O 4 alone, as is manifested by higher Faradaic efficiencies and NH 3 yield rate at − 0.64 V (52.69% vs 32.03%; 4539.61 μg h −1 mg −1 cat vs 2048.63 μg h −1 mg −1 cat ), lower energy barriers (0.96 eV vs 1.19 eV), and better electronic conductivity (Bandwidth: 0.581 eV vs 0.613 eV). In addition, this research provides an effective solution to solve the aggregation problem of metal oxide nanoparticles.
研究领域:
化学
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 18
·4336
·
IF 4.2
Yan Liao,Dashuang Wang,Wenrui Zhu,Zhilan Du,Fanbo Gong,Tuo Ping,Jinsong Rao,Yuxin Zhang,Xiaoying Liu
Transition metal oxides have been widely used in microwave-absorbing materials, but how to improve impedance matching is still an urgent problem. Therefore, we introduced urea as a polymer carbon source into a three-dimensional porous structure modified by Co3O4nanoparticles and explored the influence of different heat treatment temperatures on the wave absorption properties of the composite. The nanomaterials, when calcined at a temperature of 450 °C, exhibited excellent microwave absorption capabilities. Specifically, at an optimized thickness of 9 mm, they achieved a minimum reflection loss (RLmin) of −97.3 dB, accompanied by an effective absorption bandwidth (EAB) of 9.83 GHz that comprehensively covered both the S and Ku frequency bands. On the other hand, with a thickness of 3 mm, the RLminwas recorded as −17.9 dB, with an EAB of 5.53 GHz. This excellent performance is attributed to the multi-facial polarization and multiple reflections induced by the magnetic loss capability of Co3O4nanoparticles, the electrical conductivity of C, and the unique three-dimensional structure of diatomite. For the future development of bio-based microwave absorption, this work provides a methodology and strategy.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2019
·Vol. 9
·期 5
·408
·
IF 3.444
Chao Wang,Wenchao Hua,Guangtao Chai,Chuanhui Zhang,Yanglong Guo
Co3O4catalysts of cube and sphere shapes were prepared by one-step hydrothermal synthesis with different controlled amounts of Co(NO3)2·6H2O and NaOH. The morphological effects on both physicochemical properties and catalytic activities of vinyl chloride oxidation were investigated by material characterization and performance evaluation. The obtained results showed that the morphology, resulting in the exposure difference of crystal planes, significantly affected the catalytic property. The catalytic activity for vinyl chloride oxidation followed a descending order of Co3O4cube (Co3O4-c) > Co3O4sphere (Co3O4-s) > Co3O4commercial (Co3O4-com). The cube-shaped Co3O4presented higher catalytic activity and stability than Co3O4spheres despite their similar crystallographic structures as well as physicochemical and redox properties. Accordingly, the different catalytic behaviors should be attributed to a morphological effect. The Co3O4cube with a preferential exposure of (001) plane presented higher abundance of surface Co2+cations and adsorbed oxygen species, which acted as the active sites responsible for the improvement of its catalytic activity.Keywords:Co3O4;morphological effect;crystal plane;catalytic oxidation;vinyl chloride
研究领域:
化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
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2024
·
IF 5.5
Dongxiao Wang,Zheng Lan,Yue Li,Ying Huang,Kun Yin,Lixia Yang,Liangjiu Bai,Donglei Wei,Huawei Yang,Hou Chen,Mingchuan Luo
Comprehensive Summary Photocatalytic aerobic oxidative desulfurization (PAODS) is a sustainable alternative technology to traditional, energy-intensive fuel desulfurization methods. Nonetheless, its advancement is hindered by the notable challenge of inadequate electron-hole separation efficiency within the existing catalytic systems. Herein, a Janus 2D/2D heterostructure composed of Co 3 O 4 and CoMoO 4 is reported for the PAODS of thiophenic sulfides. Through a combination of detailed experimental characterizations and density functional theory (DFT) calculations, we elucidate the formation of a type II p-n heterojunction in the catalyst, significantly enhancing electron-hole separation through electric field force and reducing the possibility of electron-hole recombination due to the spatial separation of redox centres. The photocatalyst exhibits exceptional activity and demonstrates an impressive performance of 10.4 mmol·g –1 ·h –1 in the oxidation of dibenzothiophene (DBT). Moreover, the photocatalyst demonstrates profound desulfurization capabilities in real diesel, reinforcing its promising prospects for industrial application. These discoveries provide invaluable insights, both scientifically and practically, towards the development of advanced photocatalysts for PAODS processes.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
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2022
·Vol. 190
·期 1
·1-12
·
IF 6.408
Yan Zhengquan,Zheng Xiaoyu,Meng Guoqing,Tang Yulian,Zhou Xuemei,Hao Junkai,Feng Jing,Lin Naibo,Hu Lei
A portable sensor for visual monitoring of Fe 2+ and H 2 O 2 , two-dimensional Co 3 O 4 modified by nano-IrO 2 (IrO 2 @2D Co 3 O 4 ) was prepared in this work, for the first time, with the help of microwave radiation at 140 °C, which was further stabilized onto common test strips. The present IrO 2 @2D Co 3 O 4 possessed superior dual-function enzyme-like activity with low toxicity and excellent biocompatibility. Especially, trace Fe 2+ and H 2 O 2 could exclusively alter their enzyme-like catalytic activity with discriminating hyperchromic or hypochromic effect, i.e., from blue to colorless or to dark blue for both IrO 2 @2D Co 3 O 4 dispersion and its functionalized test strips. The linear regression equations were A 652 = 0.5940 − 0.00041 c Fe 2+ (10 −8 M, R 2 = 0.9927) for Fe 2+ and ∆A 652 = 0.0023 c H2O2 + 0.00025 (10 −7 M, R 2 = 0.9982) for H 2 O 2 , respectively. When applied to visual monitoring of aqueous Fe 2+ and intercellular H 2 O 2 , the recoveries were 101.2 ~ 102.5% and 95.8 ~ 103.7% with detection limits of 1.25 × 10 −8 mol/L and 1.02 × 10 −7 mol/L, respectively, far below the permitted values in drinking water set by the World Health Organization. The mechanisms for the enhancing enzyme-mimetic activity of IrO 2 @2D Co 3 O 4 and its selective responses to Fe 2+ and H 2 O 2 were investigated in detail. Graphical Abstract
研究领域:
分析化学
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生物医学工程
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环境科学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Liwen Wang,Guanghui Zhang,Nan An,Ruxin Li,Chang Zhou,Wenjuan Huang,Junyuan Duan,Xiangbai Chen
Hollow structure can provide more active sites and gas transmission channels for gas molecules due to their significant surface area and unique structure, showing significant performance in the field of gas sensing. Here, hollow single-shell porous C-doped Co 3 O 4 polyhedrons are successfully prepared by high temperature calcination using Co-MOF/g-C 3 N 4 precursors through a simple wet chemical method. The results show that the doping of carbon element promotes the formation of single-shell hollow porous structure. The performance test shows that the single-shell hollow porous C-doped Co 3 O 4 polyhedrons structure exhibits high sensitivity (42.41-100 ppm), low detection limit (1 ppm) and excellent selectivity to xylene at 140 ℃. The improved detection performance of the C-doped Co 3 O 4 sensor for xylene is attributed to the hollow single-shell porous structure that increases the gas adsorption area, and the incorporation of carbon atoms regulates the electronic and chemical properties of the material. This process enhances the specific surface area of material, providing more active sites for the reaction process and exhibiting stronger catalytic activity towards xylene. This study proposes a unique method to construct hollow single-shell porous structure.
研究领域:
材料科学
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传感器技术
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2024
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IF 5.1
Guangqing Zou,Heming Xu,Zhen Qi Liu,Xin Yu Qu,Guo Qiu Hou,Xue Lian Wang,Xiaolei Wang,Guimei Shi
In this work, distinct-morphological Co 3 O 4 /Nickel foams were prepared through a simple hydrothermal method and a subsequent heat treatment process. The morphology of Co 3 O 4 can be efficiently modulated from hexagonal nanosheets to nanobunches and urchin-like microspheres by manipulating the NH 4 F concentration. For the urchin-like Co 3 O 4 /Nickel foam composites, the minimum reflection loss (RL min ) value can reach −42.53 dB at a matching thickness of 2.7 mm. Theoretical analysis shows that the enhanced microwave absorption intensity is mainly originated from dielectric losses including significant interfacial polarization of the abundant interfaces, intrinsic dipoles of Co 3 O 4 and magnetic losses containing natural resonance and eddy current loss are favorable for the impedance matching. Simultaneously, multiple scattering occurring within the 3D Ni network skeleton are considered to promote the microwave absorption performance. Furthermore, a quadrilateral cone array of the resultant urchin-like Co 3 O 4 /Nickel foam composites has a RL min of −56.7 dB and an effective absorption bandwidth can achieve 9.44 GHz. This work could be beneficial for exploiting high-efficient magnetic-dielectric microwave absorption materials via the microstructural design.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2022
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IF 5.518
Chengcheng Qi,Chongchao Zhang,Ziyin Yang
Defect engineering was considered as an effective strategy to regulate electrocatalytic activities of transition metal oxides . However, there are seldom reports about metal defects in electrochemical sensing. In this work, Co-defected Co 3 O 4 was synthesized via thermal treatment of glycerolatocobalt (CoGly) precursor for constructing a novel electrochemical nonenzymatic glucose sensor. The obtained nanomaterials were characterized by transmission electron microscopy (TEM), powder X-ray diffractometry (XRD), Raman spectra , X-ray photoelectron spectroscopy (XPS) and electrochemical techniques . The presence of Co defects regulated electronic structure of Co 3 O 4 , which not only speeds up electron transfer rate but also exposes more high-valent Co sites, thus improving electrocatalytic activities. Under optimized conditions, Co-defected Co 3 O 4 electrode exhibited excellent performance for glucose analysis with a wide linear range of 0.2 µM to 0.5 mM, a low detection limit of 0.16 µM. Importantly, an ultrahigh sensitivity of 2595.7 µA·mM −1 ·cm −2 was also obtained, which was about 10 times higher than that of conventional Co 3 O 4 . Therefore, engineering Co 3 O 4 with Co defects is an effective strategy to tailor electrocatalytic activity, which sheds light on the potential applications of metal defects in the field of electrochemical nonenzymatic sensing.
研究领域:
材料科学
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电化学传感
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ELECTRONIC MATERIALS
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2022
·Vol. 51
·期 9
·5032-5041
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IF 2.047
Li Zhenhui,Chen Jianwen,Wen An,Guo Fang,Hu Dengyan,Zhu Wenbo,Chen Wenjun
Temperature-sensitive and flexible nanocomposite films are prepared by doping a poly(vinylidene fluoride) (PVDF) matrix with cobalt oxide (Co 3 O 4 ) nanoparticles. The structural and morphological characterization, dielectric properties, and conductivity of the Co 3 O 4 /PVDF nanocomposites are then systematically investigated. The nanocomposite film loaded with 10 wt.% Co 3 O 4 displays dielectric permittivity of 37 at 1 kHz, which is about 274% higher than that of pristine PVDF (13.5 at 1 kHz). The dielectric constant of the 10 wt.% Co 3 O 4 /PVDF nanocomposite as a function of absolute temperature can be fitted as \( T = 26.62 \times \ln \left( {(\varepsilon_{r} - 40.595)/1.335 \times 10^{ - 5} } \right)\) over a range of 300–423 K at 1 kHz. This fitting formula may provide important reference values for the design of flexible temperature sensors. The temperature coefficient of the dielectric constant (at 1 kHz) for the 10 wt.% Co 3 O 4 /PVDF nanocomposite film is 0.94% K −1 within a range of 350–423 K, and conductivity of about 5.78 × 10 −5 S / cm is achieved at 383 K, which is four orders of magnitude larger than that for the pristine PVDF (3.9 × 10 −9 S / cm). These results show that the addition of Co 3 O 4 nanoparticles in PVDF matrix significantly improves the dielectric constant and temperature sensitivity of the composites. Thus, the Co 3 O 4 /PVDF nanocomposites show potential application prospects in miniaturized and flexible temperature sensors.
研究领域:
材料科学
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电子工程
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Yingjie Tao,Yatao Wu,Hao Chen,Weijie Chen,Jiajie Wang,Yifei Tong,Gu Pei,Zhehong Shen,Cao Guan
Metal oxides-based materials are promising electrodes for energy storage devices, however, the low rate performance and the high energy consumption in the preparation limit their practical applications. Herein, a novel amorphous hydroxyl-rich Co 3 O 4 hierarchical structure flexible electrode is facilely fabricated via electrochemical oxidation of a cobalt-based metal-organic framework. The as-prepared Co 3 O 4 hierarchical structure is composed of large microrods and small nanoparticles and possesses abundant mesopores, amorphous, and hydroxyl-rich nature. These characteristics favor rapid electron transfer, complete exposure of the active interface, and sufficient penetration of electrolyte ions within the active material. Benefitting from these advantages, the optimal Co 3 O 4 electrode (Co 3 O 4 -5) expresses a high reversible specific capacitance ( C s ) of 226.1 C·g −1 (or 253.2 mC·cm −2 ), which is 2 (or 3.7) times higher than those of highly crystalline hydroxyl-deficient Co 3 O 4 electrode. The Co 3 O 4 -5 electrode also shows excellent rate performance (97% C s retention after a 6.7-times current increasing), which surpasses the levels of many cobalt oxide-based electrodes. In addition, an asymmetric supercapacitor (ASC) constructed from this Co 3 O 4 -5 electrode achieves a large energy density of 26.6 Wh·kg −1 (or 0.146 mWh·cm −2 ), outstanding rate capability (1% C s loss at the 10-fold higher current density), and stable cycle performance (10.1% C s loss after 20,000 charge-discharge cycles).
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2021
·Vol. 11
·期 1
·1-10
·
IF 4.38
Gong Dian,Zeng Gaofeng
Transition metal oxides are the potential catalysts to replace noble-metal based catalyst for the catalytic combustion of methane due to the tolerable reactivity and low cost. However, these catalysts are challenged by the low temperature reactivity. Herein, the surface defective Co 3 O 4 nanoplates are realized through a facile co-precipitation and thermal reduction method with the association of GO. The resultant catalysts (CoGO50) demonstrate a superior low-temperature reactivity for the methane oxidation to CO 2 and H 2 O in comparison with the common Co 3 O 4 catalyst. The reliable stability of CoGO50 catalyst was proved by 80 h testing with intermittent feeding of water vapor. The experimental analysis demonstrates that the presence of a small amount of GO significantly affects the catalysts in surface valence state, active oxygen species and surface oxygen vacancies through reacting with the cobalt oxide as a reductant. Moreover, GO plays as 2D confine template to form smaller and thinner nanoplates. This work provides a facile method to control the surface properties of catalyst not only for Co 3 O 4 based catalysts but also for wider solid catalysts.
研究领域:
化学
·
材料科学
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催化反应
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2021
·
IF 8.271
Jiani Hu,Xiaofeng Zhang,Juan Xiao,Ruchun Li,Yi Wang,Shuqin Song
To fully exploit the superiority of tubular structures, in this study, we systematically explore the optimal preparation conditions for Ni/Co 3 O 4 , including cation species and content, additive species and content, and anion species. Our results reveal that the formation of an initial cobalt nickel acetate hydroxide prism is the key factor and directly affects the final microtubular structure. Moreover, P is subsequently doped into the Ni/Co 3 O 4 lattice to increase the M 3+ /M 2+ molar ratio (M = Co and Ni), promote reaction kinetics, and optimize electronic structure. Consequently, the oxygen evolution reaction performance of P-doped tubular Ni/Co 3 O 4 is significantly higher than that of undoped Ni/Co 3 O 4 and the state-of-the-art RuO 2 electrocatalyst.
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）