Nano Energy
·
2019
·
IF 15.548
Zirui Lou,Dachao Yuan,Fengyu Zhang,Yichen Wang,Yaguang Li,Liping Zhu
CO oxidation is one of the most important catalytic reactions and it has to be run at relatively high temperature. Photothermal catalysis system could convert light as heat to drive CO oxidation rather than their conventional counterparts that use only thermal stimulus. But the light intensity required in this photothermal catalysis system is much higher than the solar intensity, restricting the application of photothermal CO oxidation. Here we present a Fe 3 Si based photothermal converted system to assist Co 3 O 4 rhombus-shaped nanorods catalysts for achieving efficient photothermal CO oxidation just under weak solar irradiation . Based on photothermal experiments, we conclude that Fe 3 Si based photo-thermal converted system can convert 0.3–0.35 kW m −2 solar irradiation into a temperature as high as 160 °C, 3 times higher than existing photothermal catalytic systems , which able to excite the activity of Co 3 O 4 rhombus-shaped nanorods for complete CO oxidation, solely irradiated by third of standard solar light and outdoor sunlight. The results suggested that the photothermal CO oxidation can be driven by ambient solar irradiation in the presence of Fe 3 Si based photothermal system and Co 3 O 4 rhombus-shaped nanorods, facilitating for industrial applications.
研究领域:
催化
·
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2021
·Vol. 28
·期 28
·37592-37602
·
IF 4.223
Li Tao,Zhao Jinxian,Quan Yanhong,Luo Dongmou,Miao Chao,Ren Jun
Co 3 O 4 nanorods with diameters of ~0.15 μm and lengths of ~1 μm were prepared using a hydrothermal method via the assembly of microcrystals and tested in the catalytic oxidation of toluene. The catalytic performance of Co 3 O 4 nanorods was improved by the addition of Ag at various concentrations, and the 7% Ag/Co 3 O 4 catalyst achieves a toluene conversion of 90% at 256 °C with a space velocity of 78,000 mL g −1 h −1 , which is much lower than that of the pristine Co 3 O 4 (269 °C). The addition of Ag promoted the activation of the surface oxygen species and the formation of more oxygen vacancies, improving the relative low-temperature reducibility of Co 3 O 4 , which is favorable for toluene oxidation. Moreover, the 7% Ag/Co 3 O 4 catalyst showed an excellent stability for toluene oxidation at 250 and 260 °C for 50 h under the same conditions.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
NANOTECHNOLOGY
·
2020
·Vol. 31
·期 25
·255501
·
IF 3.551
Huapeng Wang,Mingpeng Chen,Qian Rong,Yumin Zhang,Jicu Hu,Dongming Zhang,Shiqiang Zhou,Xinbo Zhao,Jin Zhang,Zhongqi Zhu,Qingju Liu
Xylene is a volatile organic compound which is harmful to the human health and requires precise detection. The detection of xylene by an oxide semiconductor gas sensor is an important research direction. In this work, Co3O4 decorated flower-like SnO2 nanorods (SnO2/Co3O4 NRs) were synthesized by a simple and effective two-step method. The SnO2/Co3O4 NRs show high xylene response (Rg/Ra = 47.8 for 100 ppm) and selectivity at the operating temperature of 280 °C, and exhibit high stability in continuous testing. The resulting SnO2/Co3O4 NRs nanocomposites show superior sensing performance towards xylene in comparison with pure SnO2 nanorods. The remarkable enhancement in the gas-sensing properties of SnO2/Co3O4 NRs are attributed to larger specific surface area and the formation of p–n heterojunction between Co3O4 and SnO2. These results demonstrate that particular nanostructures and synergistic effect of SnO2 and Co3O4 enable gas sensors to selectively detect xylene.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2016
·
IF 3.15
X.P. Qiu,J.S. Yu,H.M. Xu,W.X. Chen,W. Hu,G.L. Chen
A heterogeneous nanocomposite catalyst constructed by the Co 3 O 4 nanorods decorated with the Cu 2 O quantum dots (QDs) were successfully synthesized via a simple hydrothermal method followed by an oxidation-reduction processing. The fabricated Cu 2 O/Co 3 O 4 nanocomposite was characterized by the SEM, TEM, XPS, XRD, UV–vis and PL, and the (2 2 0) and (3 1 1) facets of the Co 3 O 4 were exposed. Compared with the original Co 3 O 4 nanorods with an average diameter of 350 nm, a substantial decrease in the band gap was observed after doping the nanorods with the Cu 2 O QDs (average diameter of 5 nm). Such a dramatic decrease in the band gap indicated a significant enhancement of the photocatalytic activities under visible light. The methylene blue (MB) dye and the phenol were used as model organic pollutants, and the Cu 2 O/Co 3 O 4 nanocomposite catalyst exhibited both high catalytic activity and good recycling stability. The catalytic activities of the Cu 2 O/Co 3 O 4 /potassium monopersulfate triple salt (PMS) system for cleaving the MB and the phenol were dependent on the dosages of the Cu 2 O QDs, and the calculated degradation rates achieved by 7.0 wt% Cu 2 O/Co 3 O 4 nanocomposite catalyst were about 11.3 and 1.8 times than that of the pristine Co 3 O 4 nanorod catalyst for the MB and the phenol, respectively. The reactive species of O 2 − and the holes were determined to be the main active species for the phenol photocatalytic degradation by the 7 wt% Cu 2 O/Co 3 O 4 /PMS system and the 7 wt% Cu 2 O/Co 3 O 4 /H 2 O 2 system, respectively.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2022
·
IF 13.599
Wenliang Feng,Venkata Sai Avvaru,Steven J. Hinder,Vinodkumar Etacheri
Sodium-ion hybrid capacitors (SICs) have been proposed to bridge performance gaps between batteries and supercapacitors, and thus realize both high energy density and power density in a single configuration. Nevertheless, applications of SICs are severely restricted by their insufficient energy densities (<100 Wh/kg) resulted from the kinetics imbalance between cathodes and anodes. Herein, we report a nanograin-boundary-rich hierarchical Co 3 O 4 nanorod anode composed of ∼20 nm nanocrystallites. Extreme pseudocapacitance (up to 72%@1.0 mV/s) is achieved through nanograin-boundary-induced pseudocapacitive-type Na + storage process. Co 3 O 4 nanorod anode delivers in this case highly reversible capacity (810 mAh/g@0.025 A/g), excellent rate capability (335 mAh/g@5.0 A/g), and improved cycle stability (100 cycles@1.0 A/g with negligible capacity degradation). The outstanding performance can be credited to the hierarchical morphology of Co 3 O 4 nanorods and the well-designed nanograin-boundaries between nanocrystallites that avoid particle agglomeration, induce pseudocapacitive-type Na + storage, and accommodate volume variation during sodiation-desodiation processes. Nitrogen-doping of the Co 3 O 4 nanorods not only generates defects for extra surficial Na + storage but also increases the electronic conductivity for efficient charge separation and lowers energy barrier for Na + intercalation. Synergy of conventional reaction mechanism and pseudocapacitive-type Na + storage enables high specific capacity, rapid Na + diffusion, and improved structural stability of the Co 3 O 4 nanorod electrode. The SIC integrating this highly pseudocapacitive anode and activated carbon cathode delivers exceptional energy density (175 Wh/kg@40 W/kg), power density (6632 W/kg@37 Wh/kg), cycle life (6000 cycles@1.0 A/g with a capacity retention of 81%), and coulombic efficiency (∼100%).
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Ruyi Zou,Lin Zhu,Lijun Yan,Bo Shao,Xiaoping Zhang,Wei Sun
Porous Co 3 O 4 nanorods were synthesized by the thermolysis of organometallic cobalt oxalate precursor via ultrasonic assisted method. FT-IR, XRD, XPS, SEM, TEM and BET were applied to characterize the effect of thermal treatment temperature on the properties of porous Co 3 O 4 nanorods. A three-electrode system was used to perform cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge measurements to study the electrochemical behaviours of Co 3 O 4 nanorods modified nickel foam electrodes. Compared with Co 3 O 4 prepared by pyrolysis at various temperatures, Co 3 O 4 nanorods obtained at 300 °C had the highest specific capacitance of 226.80 F·g -1 at a current density of 1 A·g -1 in the potential range of -0.4 to 0.6 V (vs. Hg/HgO). After performing 1000 cycles in 2 M KOH electrolyte, 99.76% of specific capacitance was retained, showing the excellent stability of Co 3 O 4 nanorods modified electrode.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Baohong Zhang,Lingxiao Gao,Haoze Bai,Yanhong Li,Binbin Jia,Xinyan Zhou,Anran Li,Lidong Li
Designing and optimizing electrode materials for supercapacitors (SCs) is generally considered to be an effective way to enhance their electrochemical performance. It is an attractive approach to obtaining high capacity electrodes by engineering the nanostructure and oxygen vacancies of electrodes. Herein, we developed an efficient and green strategy to facilitate one-dimensional (1D) Co 3 O 4 nanorods with abundant oxygen vacancies via Co nanorods oxidation by H 2 O 2 treatment, significantly promoting the electrochemical energy storage. The unique Co 3 O 4 NRs due to 1D nanostructure and oxygen vacancy, exhibit a high specific capacity of 627.4 mF cm −2 at a current density of 0.5 mA cm −2 and excellent rate capacity (57.8% capacitance retention at 10 mA cm −2 ). Furthermore, an asymmetric supercapacitor (ASC) constructed with the Co 3 O 4 nanorods as electrode materials shows a high energy density of 0.187 mWh cm −2 at a power density of 1.261 mW cm −2 . This nanostructure and vacancy engineering strategy put forward in this work is an inspiring example for the design of the next generation of SCs.
研究领域:
材料科学
·
电化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子