Article
Chemistry, Physical
Ruchika Mahajan, Arti Kashyap, Iurii Timrov
Summary: This study presents a first-principles investigation of the structural, electronic, and magnetic properties of pristine and Fe-doped α-MnO2 using density-functional theory. It reveals that the pristine α-MnO2 has a C2-AFM spin configuration, and that the Fe doping requires corrections to maintain this configuration.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Chemistry, Multidisciplinary
Xin Xing, Ting Zhao, Jie Cheng, Xiaoxiao Duan, Wenpeng Li, Ganggang Li, Zhongshen Zhang, Zhengping Hao
Summary: This study investigates a series of Cu-promoted Ce-Zr mixed oxide catalysts for the catalytic elimination of nitrogen-containing volatile organic compounds (NVOCs). Among them, the CeCu10%ZrOx catalyst exhibits the best catalytic performance, achieving 100% n-butylamine conversion and 90% N-2 selectivity, as well as good water resistance. The catalyst was characterized through experimental studies and theoretical calculations, and the reaction mechanism was explored. The findings highlight the potential application of this catalyst in the selective oxidation of n-butylamine.
CHINESE CHEMICAL LETTERS
(2022)
Article
Chemistry, Physical
Sylwia Gorecka, Katerina Pacultova, Aneta Smykalova, Dagmar Fridrichova, Kamil Gorecki, Anna Rokicinska, Piotr Kustrowski, Radim Zebrak, Lucie Obalova
Summary: The study showed a high correlation between the amount of copper and the efficiency of the catalysts for selective catalytic oxidation of ammonia. Copper species in the form of highly dispersed CuO oxides were found to be responsible for high N-2 selectivity, while the addition of cerium had an effect on the material's catalytic activity and N-2 selectivity. The developed materials exhibited high catalytic activity in a wide range of concentrations of ammonia and oxygen.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Xuemei Liao, Mengdie Guo, Wei Tang, Changwen Liu, Wei Luo, Lei Tan, Tomohiro G. Noguchi, Miho Yamauchi, Yonghui Zhao, Xiaopeng Li
Summary: We report a synergetic dual-metal single-atom approach that enhances the catalytic activity and selectivity of alpha-MnO2 in HMF oxidation. Pd and Ni single atoms have different roles in activating lattice oxygen and dissociating molecular oxygen. The synergistic effect of Pd and Ni accelerates the consumption and recovery of lattice oxygen, leading to a remarkable improvement in productivity and selectivity.
Article
Chemistry, Multidisciplinary
Yuezhen He, Manyue Yin, Jian Sun, Jie Chen, Kuimin Jiao, Jiantao Wen, Yan Chen, Baojuan Wang, Feng Gao, Lun Wang
Summary: Luminescent Cu@Cu2S nanozymes with high peroxidase-like and oxidase-like activity were prepared by a one-pot method. Fluorescence imaging showed that these nanozymes adhered to the surface of bacterial cells, and scanning electron microscopy revealed that the nanomaterials caused folding and collapse of the bacterial surface, resulting in bacterial death.
CHEMICAL COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Ariya K. Vijayan, M. S. Sreehari, Simran Kour, Saptarshi Ghosh Dastider, Krishnakanta Mondal, A. L. Sharma
Summary: The depletion of fossil fuels and the growing energy demand have spurred the search for renewable clean energy sources. Supercapacitors (SCs) are efficient energy storage devices that require the development of electrode materials. MnO2 has attracted wide interest for SCs due to its high theoretical capacitance, abundance, and low cost, but its low electric conductivity limits its practical applications. This study investigates the enhancement of MnO2's conductivity through cobalt doping and demonstrates improved capacitive performance, stability, and potential window. The results suggest that Co-doped MnO2 could serve as a promising electrode material for aqueous SCs and asymmetric supercapacitors.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Chao Feng, Gaoyan Xiong, Yaping Li, Qianqian Gao, Yuan Pan, Zhaoyang Fei, Yanpeng Li, Yukun Lu, Chenguang Liu, Yunqi Liu
Summary: The study found that the alpha-MnO2 nanowires with mainly exposed (110) facets exhibited the highest catalytic activity, which was attributed to the generation of reactive oxygen species and the regulation of Mn surface valence on this facet.
Article
Engineering, Environmental
Jie Zhang, Ben Dong, Ying Han, Xiaocui Zhan, Sijie Ge, Shilong He
Summary: In this study, Cobalt-doped alpha-MnO2 (Co-alpha-MnO2) was synthesized using hydrothermal method and employed for catalytic ozonation of phenol. The results showed that Co-alpha-MnO2 significantly improved the phenol removal compared to alpha-MnO2 catalytic ozonation and single ozonation without catalyst. The physicochemical properties of Co-alpha-MnO2, including larger specific surface area, higher Mn3+ content, and higher adsorbed oxygen content, contribute to its enhanced catalytic oxidation performance.
ENVIRONMENTAL ENGINEERING RESEARCH
(2023)
Article
Chemistry, Physical
Abdul Kader Mohiuddin, Mohammad Shamsuddin Ahmed, Seungwon Jeon
Summary: This study demonstrates the creation of defects by palladium atoms on the surface of alpha-MnO2 nanorods supported by graphene, leading to improved electronic and crystalline structures and enhanced surface/interface properties for biomolecule determination. The resulting material shows high sensitivity and wide detection ranges for dopamine and paracetamol, with no interference from interferents. The study also discusses the reaction mechanism of dopamine and paracetamol oxidation on the Pd@alpha-MnO2/G surface for a deeper understanding of the process.
APPLIED SURFACE SCIENCE
(2022)
Article
Chemistry, Applied
Enrico Sartoretti, Chiara Novara, Maria Cristina Paganini, Mario Chiesa, Micaela Castellino, Fabrizio Giorgis, Marco Piumetti, Samir Bensaid, Debora Fino, Nunzio Russo
Summary: Copper-ceria mixed oxides are considered promising catalysts for oxidation reactions, but their mechanistic understanding is still incomplete. In this study, pure and Cu-doped ceria samples were investigated through spectroscopic techniques, revealing the role of different copper sites and lattice defects. Cu+ species and Cu0 clusters promote CO adsorption at low temperature, while isolated Cu2+ monomers and dimers enhance lattice oxygen mobility. Changes in the structure of Cu-doped ceria occur during CO oxidation, but can be reversed and reorganized in the presence of O2. The excellent performance of Cu-doped ceria originates from the cooperation among different catalytic sites in the mixed oxide.
Article
Chemistry, Physical
Jerick Imbao, Jeroen A. van Bokhoven, Maarten Nachtegaal
Summary: The kinetic studies and X-ray absorption spectroscopy revealed the role of water in the Wacker-type ethylene oxidation, showing that water plays a key role in the reoxidation of Pd and Cu, aiding in more efficient electron transfer.
Article
Engineering, Chemical
Qiaoling Yang, Yaopeng Chen, Yao Yang, Tianxing Xu, Yin Lin, Xueliang Zhang, Jue Wang, You-Nian Liu, Yajuan Li
Summary: This study proposes a gentle method for batch synthesis of K-doped alpha-MnO2 (KMO) nanorods and reveals the chemical conversion reactions between H+, Zn2+, and MnO2. The KMO nanorods exhibit excellent cycling stability and long cycle life.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Chemistry, Physical
Ning Dong, Qing Ye, Yang Xiao, Dan Zhang, Hongxing Dai
Summary: In this study, the catalytic activity of palladium catalyst was enhanced by introducing reduced graphene oxide into the Birnessite-type MnO2 support. The best-performing catalyst, 0.48Pd-1.0rGO/δ-MnO2, exhibited high catalytic activity due to its high O-ads/O-latt molar ratio, good low-temperature reducibility, and strong interaction between palladium and δ-MnO2.
CATALYSIS SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Wei Liu, Huimin Zhu, Shan Jiang, Xuejun Zhang, Zhongxian Song
Summary: In this study, a core-shell like Au@Cu-MnO2 nanomaterial was synthesized and utilized for the catalytic removal of volatile organic compounds (VOCs). The core-shell structure was confirmed by powder X-ray diffraction, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Moreover, the results of H2-TPR and O2-TPD experiments demonstrated its enhanced reducibility and abundant adsorbed oxygen species, leading to excellent activity and stability in the deep oxidation of toluene.
Article
Chemistry, Physical
Raziyeh Jokar, Seyed Mehdi Alavi, Mehran Rezaei, Ehsan Akbari
Summary: The study found that the 10wt% CuO/MnO2 catalyst exhibited the best catalytic performance in CO preferential oxidation reaction, attributed to the synergistic interaction between copper and manganese. However, adding CO2 and/or H2O to the feedstock decreased the catalyst performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Physics, Multidisciplinary
Kejing Ran, Jinghui Wang, Song Bao, Zhengwei Cai, Yanyan Shangguan, Zhen Ma, Wei Wang, Zhao-Yang Dong, Aermak, A. Schneidewind, Siqin Meng, Zhilun Lu, Shun-Li Yu, Jian-Xin Li, Jinsheng Wen
Summary: This article presents the first polarized inelastic neutron scattering study on alpha-RuCl3 single crystals, revealing the existence of continuous magnetic excitations around the Gamma point, providing evidence for fractional excitations originating from the Kitaev quantum-spin-liquid phase, and supporting the validity of the K-Gamma model.
CHINESE PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Junxiao Chen, Xue Fang, Zhouhong Ren, Weiye Qu, Xiaolei Hu, Zhen Ma, Liwei Chen, Xi Liu, Yaxin Chen, Xingfu Tang
Summary: The development of a novel catalyst Mo-1/TiO2 enables the decomposition of ABS at low temperatures, effectively addressing the issue of SO2 deactivation in SCR catalysts. This provides a new approach to controlling NOx emissions from industrial boilers.
JOURNAL OF MATERIALS CHEMISTRY A
(2022)
Article
Physics, Multidisciplinary
Jie Wei, Qinfeng Jiang, Xiaorong Luo, Junyue Huang, Kemeng Yang, Zhen Ma, Jian Fang, Fei Yang
Summary: In this study, a novel SiC double-trench metal-oxide-semiconductor field effect transistor (MOSFET) with integrated MOS-channel diode was proposed and investigated through Sentaurus TCAD simulation. The new SiC MOSFET showed improved performance in terms of reducing the turn-on voltage and suppressing bipolar degradation phenomena. It also exhibited lower reverse recovery charge and reduced reverse recovery loss compared to the traditional SiC double-trench MOSFET. Additionally, the new MOSFET maintained superior forward conduction and blocking performance, with improved breakdown voltage and R(ON,sp) compared to the trench gate MOSFET with planar integrated SBD.
Article
Chemistry, Multidisciplinary
Weiye Qu, Haiyang Yuan, Zhouhong Ren, Jizhen Qi, Dongrun Xu, Junxiao Chen, Liwei Chen, Huagui Yang, Zhen Ma, Xi Liu, Haifeng Wang, Xingfu Tang
Summary: This study presents a solution to maximize effective adsorption and speedy surface reactions in catalysis by designing atom-pair catalytic sites with tunable electronic interactions. The strategy was successfully applied in NO selective reduction reaction, resulting in significantly higher reaction rates.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Hongyan Xue, Xiaoming Guo, Dongsen Mao, Tao Meng, Jun Yu, Zhen Ma
Summary: In this study, H3PW12O40-modified MnOx catalysts (Mn-HPW) were used for NOx elimination with co-fed NH3. The optimal Mn-HPW0.02 catalyst exhibited over 90% NOx conversion at 90-270 degrees C. The incorporation of HPW increased the amount of Lewis acid sites of the catalyst, facilitating the reaction between NH3 and NOx and enhancing the low-temperature catalytic activity. The addition of HPW also mitigated overoxidation and improved the selectivity in the high-temperature region.
Article
Energy & Fuels
Yanmin Liu, Dongsen Mao, Jun Yu, Xiaoming Guo, Zhen Ma
Summary: This paper investigates the catalytic performance of CuO-CeO2 catalyst in low-temperature CO oxidation under moisture condition. It is found that activation at 550 degrees C enhances the interaction between CuO and CeO2, leading to improved catalytic activity and moisture resistance.
Editorial Material
Multidisciplinary Sciences
Weiye Qu, Zhen Ma, Xingfu Tang
CHINESE SCIENCE BULLETIN-CHINESE
(2023)
Article
Engineering, Environmental
Weiye Qu, Xue Fang, Zhouhong Ren, Junxiao Chen, Xi Liu, Zhen Ma, Xingfu Tang
Summary: By introducing an appropriate amount of O3 into the simulated stack gas, the SCR activity at low temperatures (<250 degrees C) can be significantly enhanced. The introduction of O3 allows SCR to proceed along a NH4NO3-mediated Langmuir-Hinshelwood model, leading to the enhancement of activity at low temperatures.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Physics, Multidisciplinary
Zhen Ma, Wei-Jin Chen, Yuntian Chen, Jin-Hua Gao, X. C. Xie
Summary: We have discovered a new wave localization mechanism in a periodic wave system, which is different from Anderson localization and flat band lattices, and can produce a novel type of flat band. By designing a special periodic confinement potential, we have demonstrated complete electron localization in an open waveguide. This phenomenon, called flat band localization (FBL), is explained by the concept of self-localized orbitals, with each unit cell of the waveguide behaving like an artificial atom.
FRONTIERS OF PHYSICS
(2023)
Article
Chemistry, Physical
Dongrun Xu, Weiye Qu, Junhong Liu, Junxiao Chen, Xue Fang, Liwei Chen, Zhen Ma, Xi Liu, Xingfu Tang, Yaxin Chen
Summary: This study provides evidence that dinuclear vanadium-tungsten sites are the most active catalytic sites in conventional V2O5-WO3/TiO2 SCR catalysts, contrary to the prevailing view. These sites have stronger acidity and higher concentration of vanadium 3d electrons, leading to improved NH3 adsorption and O-2 activation in SCR. This finding settles a long-standing dispute and has important implications for understanding SCR mechanisms and designing better catalysts.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Physical
Dongrun Xu, Weiye Qu, Xiao Gu, Meiyu Li, Rui Liu, Yangyang Dong, Zhen Ma, Yaxin Chen, Xingfu Tang
Summary: This study proposes a frontier band orbital descriptor that rationalizes catalytic activity trends over a series of perovskite oxides, providing a promising strategy for designing optimal semiconducting metal oxide catalysts.
Article
Chemistry, Multidisciplinary
Rui Liu, Weiye Qu, Xiaolei Hu, Junxiao Chen, Yangyang Dong, Dongrun Xu, Jing Liu, Zhen Ma, Xingfu Tang
Summary: The valence state of single Au atoms anchored on CeO2(100) can be tuned to enhance the CO oxidation activity of Au-1/CeO2(100) by one order of magnitude. This work is significant for understanding reaction mechanisms and designing high-performance catalysts.
CHEMICAL COMMUNICATIONS
(2022)
Article
Engineering, Environmental
Su Liu, Lin Zhang, Haibo Zhou, Zhen Ma, Yangdong Wang
Summary: The type of surfactant used significantly affects the properties and catalytic performance of Mo-Co-K sulfide catalysts, with the cationic surfactant CTAB enhancing the activity of the catalyst in CO2 hydrogenation reaction.
CHEMICAL ENGINEERING JOURNAL ADVANCES
(2022)
