Mechanochemically synthesized Fe-Mn binary oxides for efficient As(III) removal: Insight into the origin of synergy action from mutual Fe and Mn doping

Of the four groups of crystal lattice defects, i.e., point defects, dislocations, interfaces and particles, dislocations are often thought to be the least important for ceramic materials. However, they not only give considerable insight into interfaces (they can be thought of as the link between point defects and interfaces), but they are becoming more important as interest grows in epitactic oxide heterostructures.The present paper provides a review of our current understanding of dislocations in ceramics. To simplify the discussion, we can separate the task into the following sections, namely Simple oxides (MgO, ZnO etc.)Simple non-oxides (A1N, GaN, SiC, TiC, etc.)More complex binary oxides (AI2O3, Fe203, etc.)Multicomponent oxides and complex non-oxides (spinels, garnets, S13N4)Interfacial dislocations (misfit, grain boundary, etc.)The features which are most often associated with ceramic materials are their complex structures and large unit cells. For example in bcc garnets, the smallest Burgers vector for a perfect lattice dislocation is ∼0.8nm long.

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A theoretic insight into the catalytic activity promotion of CeO2 surfaces by Mn doping

Physical Chemistry Chemical Physics ◽

10.1039/c2cp00061j ◽

2012 ◽

Vol 14 (16) ◽

pp. 5769 ◽

Cited By ~ 91

Author(s):

Wanglai Cen ◽

Yue Liu ◽

Zhongbiao Wu ◽

Haiqiang Wang ◽

Xiaole Weng

Keyword(s):

Catalytic Activity ◽

Mn Doping ◽

Activity Promotion ◽

Insight Into

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Inducing ferromagnetism in pyrochlore Eu2Ti2O7by Fe and Mn doping and establishing ferroelectricity in Eu2Ti2O7

Proceedings of the International Conference on Nanotechnology for Better Living ◽

10.3850/978-981-09-7519-7nbl16-rps-141 ◽

2016 ◽

Author(s):

Arkadeb Pal ◽

A. Singh ◽

Sandip Chatterjee

Keyword(s):

Mn Doping ◽

Fe And Mn

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Anthropogenic Organic Pollutants in Groundwater Increase Releases of Fe and Mn from Aquifer Sediments: Impacts of Pollution Degree, Mineral Content, and pH

Water ◽

10.3390/w13141920 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1920

Author(s):

Yuanzheng Zhai ◽

Yifan Han ◽

Xuelian Xia ◽

Xindai Li ◽

Hong Lu ◽

...

Keyword(s):

Mineral Content ◽

Anthropogenic Activities ◽

Scientific Evidence ◽

Leaching Test ◽

Groundwater System ◽

The World ◽

Fe And Mn ◽

Aquifer Sediments ◽

Insight Into ◽

Kinetic Equilibrium

In many aquifers around the world, there exists the issue of abnormal concentrations of Fe and Mn in groundwater. Although it has been recognized that the main source of this issue is the release of Fe and Mn from aquifer sediments into groundwater under natural environmental conditions, there lacks enough reliable scientific evidence to illustrate whether the pollutants imported from anthropogenic activities, such as organics, can increase this natural release. On the basis of time series analysis and comparative analysis, the existence of an increasing effect was verified through laboratorial leaching test, and the impacts of aquatic chemical environment conditions, such as pH, on the effect were also identified. The results showed that the increase of organics in groundwater made the release of Fe and Mn more thorough, which was favorable for the increase of groundwater concentrations of Fe and Mn. The higher the contents of Fe- and Mn-bearing minerals in aquifer sediments, the higher the concentrations of Fe and Mn in groundwater after the release reaches kinetic equilibrium. Lower pH can make the leaching more thorough, but the neutral environment also increases the amount of Mn. It can be deduced that the pollutants such as organics imported by anthropogenic activities can indeed increase the releases of Fe and Mn from aquifer sediments into groundwater, thus worsening the issue of groundwater Fe and Mn pollution. The findings provide a deeper insight into the geochemical effects of Fe and Mn in the natural environment, especially in the groundwater system.

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Modifying the Electronic and Optical Properties of Nano ZnS via Doping With Mn and Fe

10.21203/rs.3.rs-241301/v1 ◽

2021 ◽

Author(s):

Zein Heiba ◽

Mohamed Mohamed ◽

H. El Shimy ◽

Ali Badawi

Keyword(s):

Fourier Transforms ◽

Atmospheric Oxygen ◽

Lattice Parameter ◽

Mn Doping ◽

Fe And Mn ◽

Fourier Transforms Infrared Spectroscopy ◽

New Applications ◽

Theory Calculation ◽

Zn Ions ◽

Mn Doped

Abstract 5% Fe and Mn-doped nano ZnS (Zn0.95A0.05S, A=Fe or Mn) was prepared using the thermolysis technique. The effect of Fe and Mn doping on the lattice parameter, crystallite size, and lattice microstrain was examined applying Rietveld refinement. The analysis showed the incorporation of Fe and Mn substitutionally for Zn ions; a result confirmed by Fourier transforms infrared spectroscopy spectra from the shift in the vibration bands upon doping. The energy of ZnS band gap was reduced by doping, giving ZnS new applications. The different defects inside the different samples were investigated using photoluminescence spectroscopy. The effect of Fe/ Mn doping and incorporation of atmospheric oxygen on the bandgap characteristics, the absorption, optical conductivity, refractive index and the extinction coefficient, reflectance, the real and imaginary parts of the dielectric constant were explored using density function theory calculation (DFT).

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