ELECTROCHIMICA ACTA
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2020
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IF 6.215
Gang Liu,Lin Ma,Qiming Liu
The attempt of high output potential character has always been an enormous challenge for water-based supercapacitors. In this paper, we first synthesize leaf-like Co 3 O 4 @MnO 2 nanosheets on the carbon cloth fibers (Co 3 O 4 @MnO 2 CC) with hierarchical core-shell structure via a facile chemical bath deposition at low temperature. This leaf-like Co 3 O 4 @MnO 2 nanosheets not only afford the advantage of ultra-high output potential (1.2 vs (Ag/AgCl)/V), but also carry the superiorities of ultra-high specific capacitance (616.7 F g −1 at 2 A g −1 ) and remarkable cyclic stability (83.1% retention after 10000 cycles at 20 A g −1 ). The asymmetrical supercapacitor, assembled by using Co 3 O 4 @MnO 2 @CC-90 (CoMn@CC-90) as cathode and active carbon (AC) as anode, exhibits multiple merits of extra-high output potential (2.2 V vs AC/V), splendid specific energy (54.71 W h kg −1 at power density of 1.06 k W kg −1 ) and long cycle life (86.3% capacitance retention after 10000 cycles). Our work offers one novel kind of reference for water-based supercapacitors with both characteristics of high output potential and high specific capacitance.
研究领域:
材料科学
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能源存储技术
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2017
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IF 3.133
Wei Guo,Linlin Hou,Biao Hou,Yalin Guo
Pseudocapacitive materials, e.g. , MnO 2 and Co 3 O 4 , can significantly enhance the energy density of supercapacitors because of Faradaic reactions that can take place with these materials. Single-component electrodes have shown insufficient performance due to limited variations in electrode structures. Herein, we report a hierarchical electrode through growing networked Co 3 O 4 @MnO 2 hierarchical nanosheets (HNS) arrays directly on Ni foam. We adopt a one-step hydrothermal reaction followed by a simple staged post-annealing treatment which simplifies the synthesis procedure. When used as electrodes for supercapacitors, the Co 3 O 4 @MnO 2 HNS electrode shows good electrochemical performance, such as high areal/specific capacitances of 2.85 F cm −2 /2374 F g −1 at a current density of 1 mA cm −2 and long-term cycling stability of 4500 cycles. These encouraging results demonstrate this electrode design strategy is promising for developing high capacitance electrode materials for high energy density supercapacitors.
研究领域:
材料科学
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能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Zhuo-Rui Jiang,Yuxin Li,Yu-Xiao Zhou,Xiaoyu Liu,Changhua Wang,Yeqing Lan,Ying Li
Co 3 O 4 -MnO 2 /BC, as an efficient activator of peroxymonosulfate (PMS) for the decomposition of soluble sulfonamide antibiotics, was successfully obtained via anchoring Co 3 O 4 -MnO 2 nanoparticles on rice straw biochar (BC). The results demonstrated that 25 mg/L sulfadiazine (SDZ) could be thoroughly destructed by a combination of PMS (1 mM) and Co 3 O 4 -MnO 2 /BC (0.1 g/L) within 10 min. The pseudo-first-order rate constant ( k ) of the SDZ degradation was high up to 0.482 min −1 , which was much larger than those reported in previous literature. The superior stability of the catalyst was confirmed through 5 recycle runs with approximately 100% degradation of SDZ and less than < 0.7 mg/L leached metal ions. Singlet oxygen ( 1 O 2 ) and sulfate radicals (SO 4 •− ) were proved to be the principal reactive oxygen species (ROS) responsible for the degradation of SDZ. Combining the identification of ROS as well as intermediates during the SDZ degradation process, the possible catalytic mechanisms and the pathways of the SDZ degradation were deduced. The results further demonstrated that the combination of Co 3 O 4 -MnO 2 /BC and PMS also possessed a universal degradation capacity towards other typical organic pollutants, such as sulfisoxazole, sulfamethoxazole, bisphenol A and phenacetin. This is the first report on high-efficient heterogeneous activating PMS by Co 3 O 4 -MnO 2 /BC to eliminate soluble sulfonamide antibiotics, which makes it valuable for developing eco-friendly and efficient catalysts for the PMS activation.
研究领域:
环境科学
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催化
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水处理
✓ 已验证
DOI
高影响因子
Batteries & Supercaps
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2025
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IF 4.7
Xu Zhang,Heng Xiang,Chuang Pang,Keyu Zhao,Zhongli Zou,Kui Cheng
The development of flexible energy-storage devices is limited by the poor conductivity, limited cycling stability, and slow electron/ion transport of metal oxides. Optimizing their structure and performance is crucial for advancing these technologies. Herein, a hollow cubic core–shell Co 3 O 4 @MnO 2 is synthesized via annealing and hydrothermal approaches. This composite enjoys advantages of the high electrical conductivity of Co 3 O 4 and the excellent pseudocapacitive properties of MnO 2 ; in addition, the hollow structure of the composite effectively mitigates the mechanical stress caused by volume changes during charge–discharge cycles. Owing to its large specific surface area and stable framework, Co 3 O 4 @MnO 2 achieves a high specific capacitance of 670.2 F g −1 and retains 83.18% of its initial capacitance after 10,000 cycles, demonstrating exceptional electrochemical stability and durability. Subsequently, an all-solid-state flexible supercapacitor was assembled using Co 3 O 4 @MnO 2 positive electrode and a negative electrode made of reduced graphene oxide hydrogel. The device achieves a high energy density of 78.2 W h kg −1 and a power density of 11,500 W kg −1 . Further, even after 10,000 charge–discharge cycles, it retained 73.1% of its initial capacitance, demonstrating potential for flexible energy-storage applications. This article highlights the advantages of Co 3 O 4 @MnO 2 in enhancing supercapacitor performance and offers insights for cost-effective cobalt-based energy-storage systems. Graphical The diagram illustrates the synthesis process of Co 3 O 4 @MnO 2 composites, in which a hollow core–shell structure is successfully constructed with Co 3 O 4 cages serving as the core and MnO 2 nanosheets as the shell.
✓ 已验证
DOI
高影响因子
FUEL
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2025
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IF 7.5
Suhong Lu,Nan Sun,Liwei Gong,Chengyu Xu,Rongrong Guo,Yiyao Li,Shuo Wang,Jurong Liu,Yuzhen Fang,Guilong Liu
Hollow urchin-like Co 3 O 4 -MnO 2 spheres were synthesized via hydrothermal method, followed by co-impregnation with 3 wt% Ag and K (3, 5, 7 wt%). The optimized Ag-5 K/Co 3 O 4 -MnO 2 catalyst achieved complete HCHO conversion at 50 °C under 150 ppm HCHO, 21 vol% O 2 /N 2 , RH = 30 %, and WHSV = 36,000 mL g cat -1 h −1 . Systematic parameter studies (0 ∼ 80 % RH, 50 ∼ 350 ppm HCHO, 5 ∼ 21 vol% O 2 , 36,000 ∼ 144,000 mL g cat -1 h −1 WHSV) demonstrated the robust catalytic performance of Ag-5 K/Co 3 O 4 -MnO 2 across wide operational ranges. Remarkably, Ag-5 K/Co 3 O 4 -MnO 2 demonstrated excellent stability and nearly 100 % HCHO conversion over a continuous period of 100 h with the WHSV of 36,000 mL g cat -1 h −1 . The hollow architecture enhanced reactant diffusion, while interconnected nanorod arrays provided abundant Ag/K anchoring sites. Potassium doping increased Ag/Ag + , (Mn 2+ + Mn 3+ )/Mn 4+ and Co 3+ /Co 2+ ratios via strengthened Ag-support interactions, promoting oxygen activation. Mechanistic analysis indicated HCHO oxidation proceeds via HCHO → DOM → HCOO – + OH – →CO 2 + H 2 O route.
✓ 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）