POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Yingbing Zou,Kui Niu,Fubin Luo,Hongzhou Li
The development of metal oxide flame retardants that are easy to synthesize, efficient, and recyclable would be more beneficial to circular economy. In this work, a porous core-shell Mn 3 CoO x was developed to efficiently reduce heat, smoke as well as hazardous gas during the combustion of epoxy resin (EP). Compared with pure EP, the peak heat release rate (pHRR), total heat release (THR), peak smoke production rate (pSPR), total smoke production (TSP), peak CO production rate (pCOPR), and peak CO 2 production rate (pCO 2 PR) of EP/Mn 3 CoO x are reduced by 47.5 %, 21.5 %, 34.6 %, 17.6 %, 58.6 %, and 55.4 %, respectively. It has been shown that Mn 3 CoO x not only catalyzes the formation of high-quality char layer but also effectively catalyzes the conversion of hazardous gas products into CO 2 . Recovery experiments of Mn 3 CoO x filler in EP composites show that the recovery of Mn 3 CoO x can reach 90.0 %. This work provides insights into the design of efficient metal oxide flame retardants and ideas for the development of recycled flame retardants.
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
CATALYSIS TODAY
·
2019
·
IF 4.888
Tianyu Gao,Yongxuan Yin,Guanghui Zhu,Qiue Cao,Wenhao Fang
Oxidative transformations of HMF are key routes toward a wide variety of chemicals and biofuels through an environmental friendly process. Co 3 O 4 NPs decorated Mn-Co-O solid solution, donated as Co 3 O 4 /Mn X Co, was prepared by co-precipitation method and used as non-precious metal catalyst for base-free oxidation of HMF to FDCA in the presence of O 2 and water. Comprehensive characterizations such as XRD, H 2 -TPR, O 2 -TPD, XPS, NH 3 /CO 2 -TPD and TEM were used to study materials properties especially the oxygen mobility and acidity-basicity. The effect of Mn/Co molar ratio in catalyst and the reaction conditions were investigated and optimized. In addition, the kinetics of the reaction was monitored to reveal the reaction route and rate-determining step. The variation of Mn/Co molar ratio was found to affect not only HMF conversion but also distribution of products. When the Mn/Co ratio was of 0.2, the Co 3 O 4 /Mn 0.2 Co catalyst showed the optimal catalytic performance (i.e., >99% yield of FDCA obtained under 1 bar O 2 at 140 °C after 24 h) due to the highest content of both Lewis and Brønsted acid sites on the surface, leading to the strongest ability of HMF adsorption and COOH group formation, as well as the enhanced oxygen mobility. This catalyst was shown stable after a minor deactivation (≤8%) during six recycling uses and its activity can be entirely regenerated by calcination in air.
研究领域:
催化化学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Enhui Wu,Xiaoshan Feng,Yingbin Zheng,Daifeng Lin,Yongjin Luo,Yufeng You,Baoquan Huang,Qingrong Qian,Qinghua Chen
Mn–Co–O catalysts with different Mn/Co molar ratios were synthesized by means of a facile inverse coprecipitation strategy and applied for the oxidation of propane (C3H8). The XRD pattern of Co2Mn1Oδ (molar ratio of Mn:Co = 1:2) indicates a Co3O4 phase, and most Mn incorporates into Co3O4 lattice to form a solid solution. Minor distributed Mn species occur structure reforming, totally converting to a stable Co–Mn solid solution during oxidation process. Meanwhile, Co2Mn1Oδ features a porous core–shell morphology, the core and shell of which are made up of Co–Mn solid solution, giving rise to a high surface area. The optimized synergistic effect of manganese and cobalt improves low temperature reducibility and produces rich surface active Co3+ species and surface-absorbed oxygen over Co2Mn1Oδ. As a result, it exhibits a prominent excellent catalytic activity, and delivers good thermal stability in the presence of 5 vol % H2O and 5 vol % CO2. In situ DRIFTs analysis displays the reaction path of C3H8 over Co2Mn1Oδ, where dominate intermediate species formate are easily decomposed into CO2. The synthesized porous core–shell Mn–Co–O can be a promising candidate replacing non-noble catalysts toward C3H8 oxidation at low temperature.
研究领域:
催化化学
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环境化学
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材料科学
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多相催化
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能源与环境科学
✓ 已验证
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 11
·3526-3536
·
IF 4
Junxiang Zhou,Yudeng Wang,Bo Feng,Yong Sun,Jiafu Wang
Ternary transition metal oxides (TMOs) are potentially promising anode materials for lithium storage with high power and energy density. Designing appropriate electrode structures is an effective strategy to sufficiently exhibit the advantages of TMOs for lithium storage. Here, we present the synthetic process and electrochemical properties of carbon-coated mesoporous Ni–Mn–Co–O (NMCO) nanowire arrays (NWAs) grown on Ni foam as an integrated electrode for lithium-ion batteries (LIBs). The electrochemical measurements show that the carbon-coated NMCO integrated electrode exhibits high capacity and cycling properties. In addition, we have also developed an all one-dimensional (1D) structural full cell using an LiMn2O4 nanorod cathode and an NMCO/Ni NWAs@C-550 anode, which exhibits relatively outstanding cycling properties.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
PubMed
高影响因子