نتایج جستجو برای: mn2o3 nanoparticle

تعداد نتایج: 31103  

2015
Yohan Park Sung Woo Lee Ki Hyeon Kim Bong-Ki Min Arpan Kumar Nayak Debabrata Pradhan Youngku Sohn

Manganese oxides are one of the most valuable materials for batteries, fuel cells and catalysis. Herein, we report the change in morphology and phase of as-synthesized Mn2O3 by inserting Na(+) ions. In particular, Mn2O3 nanoparticles were first transformed to 2 nm thin Na0.55Mn2O4·1.5H2O nanosheets and nanobelts via hydrothermal exfoliation and Na cation intercalation, and finally to sub-mm ult...

Journal: :Symmetry 2022

One of the current problems in environmental catalysis is design an effective and less costly catalytic system for oxidation CO. The nano-sized α-Mn2O3 oxide has been prepared modified with 0.5 wt.% Pt. catalysts have characterized by X-ray diffraction (XRD), photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), temperature-programmed reduction (TPR) diffuse-reflectance infr...

Journal: :Catalysts 2023

Three types of α-Mn2O3 catalysts with different well-defined morphologies (cubic, truncated octahedra and octahedra) exposed crystal facets have been successfully prepared via hydrothermal processes, evaluated for ethanol total oxidation low concentration at temperatures. The α-Mn2O3-cubic catalyst shows a superior catalytic reaction rate than that α-Mn2O3-truncated α-Mn2O3-octahedra under high...

2015
Matthias Augustin Daniela Fenske Ingo Bardenhagen Anne Westphal Martin Knipper Thorsten Plaggenborg Joanna Kolny-Olesiak Jürgen Parisi

Manganese oxides are one of the most important groups of materials in energy storage science. In order to fully leverage their application potential, precise control of their properties such as particle size, surface area and Mn (x) (+) oxidation state is required. Here, Mn3O4 and Mn5O8 nanoparticles as well as mesoporous α-Mn2O3 particles were synthesized by calcination of Mn(II) glycolate nan...

Journal: :Journal of Cleaner Production 2021

The crucial role of manganese(III) species in the oxidative and catalytic reactivity manganese oxides have been widely reported. However, direct activation radical precursors by Mn(III) is still a matter discussion. In this work, ability Mn(III)-bearing oxide (Mn2O3) for peroxydisulfate (PS) peroxymonosulfate (PMS) was evaluated compared using caffeine (CAF) as model pollutant. Complete CAF rem...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2014
Nancy Birkner Alexandra Navrotsky

Chemisorption of water onto anhydrous nanophase manganese oxide surfaces promotes rapidly reversible redox phase changes as confirmed by calorimetry, X-ray diffraction, and titration for manganese average oxidation state. Surface reduction of bixbyite (Mn2O3) to hausmannite (Mn3O4) occurs in nanoparticles under conditions where no such reactions are seen or expected on grounds of bulk thermodyn...

2017
Pengwei Wang Guofeng Zhao Yu Wang Yong Lu

Oxidative coupling of methane (OCM) is a promising method for the direct conversion of methane to ethene and ethane (C2 products). Among the catalysts reported previously, Mn2O3-Na2WO4/SiO2 showed the highest conversion and selectivity, but only at 800° to 900°C, which represents a substantial challenge for commercialization. We report a TiO2-doped Mn2O3-Na2WO4/SiO2 catalyst by using Ti-MWW zeo...

2009
Ping Hu Hai-bo Yang De-an Pan Hua Wang Jian-jun Tian Xin-feng Wang Alex A. Volinsky

Mn–Zn ferrite powders (Mn0.5Zn0.5Fe2O4) were prepared by the nitrate–citrate auto-combustion method and subsequently annealed in air or argon. The effects of heat treatment temperature on crystalline phases formation, microstructure and magnetic properties of Mn–Zn ferrite were investigated by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning electron microscopy a...

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2013
Nancy Birkner Sara Nayeri Babak Pashaei Mohammad Mahdi Najafpour William H Casey Alexandra Navrotsky

Previous measurements show that calcium manganese oxide nanoparticles are better water oxidation catalysts than binary manganese oxides (Mn3O4, Mn2O3, and MnO2). The probable reasons for such enhancement involve a combination of factors: The calcium manganese oxide materials have a layered structure with considerable thermodynamic stability and a high surface area, their low surface energy sugg...

Journal: :Dalton transactions 2015
Ning Li Peter D Matthews Jane J Leung Timothy C King Paul T Wood He-Kuan Luo Dominic S Wright

The novel heterometallic polyoxotitanate cage [Ti18MnO30(OEt)20(MnPhen)3] (1), obtained by solvothermal reaction of Ti(OEt)4 with Mn(AcO)3·(H2O)2 and 1,10-phenanthroline (Phen) in EtOH, has a C3 symmetric core structure containing an interstitial tetrahedral Mn(II) ion and is surrounded by three Mn(II)(Phen) fragments. The molecular structure is retained in thin film electrodes of 1 deposited b...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید