Article
Engineering, Chemical
Ehsan Akbari, Seyed Mehdi Alavi, Mehran Rezaei, Afsanehsadat Larimi
Summary: Different morphologies of MnOx nanocrystalline catalysts prepared using hydrothermal and solution methods showed varying performance in catalytic combustion of methane, with the wire-like MnO2 catalyst exhibiting excellent efficiency. Various synthesis factors significantly influenced the structure and activity of the catalysts, with a specific sample showing the highest efficiency under certain conditions. The stability of the optimal MnO2 sample decreased slightly in the presence of CO2 and water vapor, but displayed high stability under dry feed conditions at higher temperatures for an extended period.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2021)
Article
Chemistry, Multidisciplinary
Yan Cui, Huikang Song, Yiyu Shi, Pengxiang Ge, Mindong Chen, Leilei Xu
Summary: A series of CuO-based catalysts supported on alpha-MnO2 nanowires were synthesized and their catalytic performance was evaluated. The slenderness ratio of the catalyst was found to decrease with increasing CuO loading, and the catalyst supported by the deposition precipitation method showed the highest catalytic activity.
Article
Materials Science, Ceramics
Jian Zhang, Fubiao Gu, Chang-An Wang
Summary: A method utilizing the Kirkendall effect was successfully used to prepare multi-shelled MnO2-Co3O4 hollow spheres which exhibited high activity and stability in CO oxidation reactions. This work provides a new approach for the preparation of multi-shell composite hollow spheres.
CERAMICS INTERNATIONAL
(2021)
Article
Engineering, Environmental
Yanling Sun, Xiaotong Wang, Yongli Dong, Xiaoyu Niu, Yujun Zhu
Summary: MnO2, MnO2-M, and MnO2-CM were synthesized using different precursors through a one-pot hydrothermal method and applied for the catalytic oxidation of toluene. Various characterization techniques were used to accurately determine the physicochemical properties of the catalysts. The Cu and Mn co-modified MnO2-CM exhibited a nanosphere morphology composed of worm-like particles. It demonstrated superior low-temperature catalytic oxidation activity, long-term stability, and resistance to H2O, with a 90% toluene conversion temperature of approximately 207 degrees C and a low apparent activation energy of 31.7 kJ·mol-1. This is attributed to the strong interaction between Cu and Mn, which promotes the generation of oxygen vacancies in MnO2-CM, facilitating gaseous oxygen activation and enhancing the oxidation ability at low temperatures.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Nanoscience & Nanotechnology
Qinghe Liu, Sen Wang, Fei Han, Shupei Lv, Zairong Yan, Yunfei Xi, Jing Ouyang
Summary: Highly efficient three-dimensional kaolinite/MnO2-CuO catalysts were synthesized using a mild biomimetic strategy. The catalyst exhibited excellent stability and high CO conversion efficiency due to the unique structure of uniformly wrapped kaolinite flakes and ultrathin MnO2 nanosheets, as well as abundant oxygen vacancies.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Engineering, Environmental
Ying Du, Fengyu Gao, Yuansong Zhou, Honghong Yi, Xiaolong Tang, Zhiyong Qi
Summary: Carbon monoxide and nitric oxide are widely present in industrial flue gas and pose risks to human health and the environment. The use of CuO-CeO2 composite oxide catalysts shows promising results in the removal of CO and NO, which is important for reducing air pollution. Further research is needed to optimize the performance of these catalysts for industrial applications.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2021)
Article
Energy & Fuels
Wei Liu, Wenjie Xiang, Xi Chen, Zhongxian Song, Chunxiang Gao, Noritatsu Tsubaki, Xuejun Zhang
Summary: The solid-state redox strategy efficiently increased the oxygen vacancy concentration of CuO/MnO2-R catalyst, enhancing its catalytic performance in toluene combustion. Strengthening surface defects resulted in a significant decrease in T-90 for CuO/MnO2-R-10 catalyst, which also exhibited excellent stability and resistance to water vapor, showing great potential for practical applications.
Article
Chemistry, Inorganic & Nuclear
Xi Liang, Shuaishuai Zhang, Meng Zhao, Jing Xu, Yang Yu, Shuyan Song, Hongjie Zhang
Summary: Co3O4/CeO2 multi-shelled nanospheres with various Ce/Co ratios were prepared using a bimetallic coordination polymer as a sacrificial template for low-temperature CO oxidation. The addition of cerium significantly increased the surface area, enriching oxygen vacancies and enhancing accessible active sites, leading to superior catalytic performance. This work presents an alternative approach for constructing multi-shelled nanosphere composites.
DALTON TRANSACTIONS
(2021)
Review
Chemistry, Physical
Weidong Zhang, Jose Luis Valverde, Anne Giroir-Fendler
Summary: This review summaries the potential of Co3O4-based catalysts for volatile organic compounds (VOCs) elimination. Recent progress on single, composite, and supported Co3O4 catalysts for propane oxidation is comprehensively discussed. The design and construction of composite Co3O4 are presented in detail, as well as the industrial applications of supported Co3O4 systems. The mechanisms of propane oxidation and poisoning effects on Co3O4-based catalysts are summarized, and the challenges, opportunities, and future research directions for developing advanced Co3O4-based catalysts are prospected.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Chemistry, Applied
Hajime Hojo, Yuka Inohara, Ryo Ichitsubo, Hisahiro Einaga
Summary: In this study, LaNiO3 was prepared and modified with Mn, and its catalytic activity for CO and benzene oxidation was investigated. LaNiO3 showed higher CO oxidation activity than other perovskite oxides, which was attributed to the reactivity of the lattice oxygen. Mn-modified LaNiO3 exhibited higher activity for benzene oxidation, and the catalytic properties were correlated with the amount of Mn on the catalyst surface.
Article
Chemistry, Physical
Jithin Gopakumar, Sunniva Vold, Bjorn Christian Enger, David Waller, Per Erik Vullum, Magnus Ronning
Summary: The Ostwald process is the most common industrial process for producing nitric acid. This research focuses on catalytic oxidation of NO to NO2 using silver-promoted manganese on zirconia catalysts under industrially relevant conditions. The results show that the manganese catalysts can work effectively at low temperatures and concentrations relevant to industrial catalytic oxidation of NO.
CATALYSIS SCIENCE & TECHNOLOGY
(2023)
Review
Environmental Sciences
Pijun Gong, Feng He, Junlin Xie, De Fang
Summary: Volatile organic compounds (VOCs) pose serious threats to human health and the ecological environment. Catalytic oxidation technology, due to its cost-effectiveness and high activity, is considered the most effective method for removing VOCs. This review summarizes the research progress in the catalytic oxidation of toluene using MnO2-based catalysts, including single MnO2, metal-doped MnO2, and supported MnO2 catalysts. The relationship between the chemical properties of MnO2 catalysts and toluene oxidation performance, as well as the catalytic reaction mechanisms, are focused on. Additionally, the effects of different crystal forms and morphologies on the catalytic toluene reaction are discussed, and the potential of MnO2 catalysts for the catalytic oxidation of toluene is proposed. The summary of these important findings is expected to serve as a valuable reference for the catalytic treatment of VOCs.
Article
Chemistry, Physical
Zihao Li, Xianhuai Chen, Jinghuan Chen, Huazhen Chang, Lei Ma, Naiqiang Yan
Summary: In this study, nanoflower-like Co3O4 diesel oxide catalysts (DOCs) with the addition of low-content Pt were fabricated to improve the oxidation activity at low temperature for multi-pollutant diesel exhaust. The as-synthesized Pt/Co3O4 catalysts showed better multi-pollutant oxidation activities and resistance towards NO inhibition compared to conventional Pt/Al2O3 DOCs. Furthermore, the Pt/Co3O4 catalysts exhibited exceptional hydrothermal durability and promoted low-temperature catalytic activity through increasing surface oxygen species and reducibility.
Article
Chemistry, Physical
Jia Zeng, Hongmei Xie, Zhao Liu, Xuecheng Liu, Guilin Zhou, Yi Jiang
Summary: This study demonstrates the tuning of oxygen vacancies on alpha-MnO2 for catalytic toluene oxidation, resulting in superior activity and stability. The control of oxygen vacancies weakens the Mn-O bond strength, increases the amount of surface adsorbed active oxygen species, and promotes catalytic activity.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Chemistry, Physical
Xin Yu, Tingke Jin, Huiqiang Wang, Guoqing Zhang, Wenlong Jia, Lincai Peng, Yong Sun, Xing Tang, Xianhai Zeng, Shuliang Yang, Zheng Li, Feng Xu, Lu Lin
Summary: A cost-effective and sustainable catalyst system based on Mn-Cu bimetallic oxides was found to be highly efficient for the selective oxidation of furfural to furancarboxylic acid. The incorporation of CuO into the Mn-Cu oxides weakened the Mn-O bonds, resulting in improved catalytic activity. The study provides insights into the relationship between the morphology, surface chemistry, and catalytic activity of Mn-Cu bimetallic oxides.
GREEN ENERGY & ENVIRONMENT
(2023)