Bentonite/Iron Oxide Composites: Preparation and Characterization by Hyperfine Methods

Bentonite/iron oxide system is prepared by isothermal calcination of powder composed of bentonite clay and precursor containing ferric acetate. This preparation technique enables one to get the composite material directly, that is, iron oxide particles embedded in a bentonite matrix. Calcination temperatureTcalcis varied from 320°C to 700°C. The resulting series of samples is characterized by local methods based on hyperfine interactions:57Fe nuclear magnetic resonance (NMR) and the Mössbauer spectroscopy. The results show that the phase composition changes significantly in dependence on calcination temperature. The amount of maghemite phase rapidly increases up toTcalc=420°C and decreases abruptly forTcalchigher than 460°C.

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INVESTIGATION OF SURFACES OF NOVEL IRON OXIDES WITH GRAIN AND GRAIN BOUNDARY

Vietnam Journal of Science and Technology ◽

10.15625/2525-2518/56/1a/12527 ◽

2018 ◽

Vol 56 (1A) ◽

pp. 226

Author(s):

Nguyet Viet Long

Keyword(s):

Heat Treatment ◽

Iron Oxide ◽

Grain Boundary ◽

Iron Oxides ◽

Particle System ◽

Oxide Particle ◽

Oxide System ◽

Iron Oxide Particle ◽

Iron Oxide Particles ◽

Oxide Particles

Hierarchical nano/microscale α-Fe2O3 iron oxide particle system was prepared by an improved and modified polyol method with the use of NaBH4 agent with high heat treatment at 900 °C in air. Here, α-Fe2O3 iron oxide particles with different shapes were analyzed. The morphologies of the surfaces of α-Fe2O3 iron oxide particles show the oxide structures with the different nano/microscale ranges of grain sizes. In this research, we have found that grain and grain boundary growth limits can be determined in α-Fe2O3 iron oxide structure. This leads to the possibility of producing new iron oxide structures with distribution of desirable size grain and grain boundary. With α-Fe2O3 structure obtained, the magnetic properties of the α-Fe2O3 iron oxide system are different from those of previously reported studies. in national and international studies.Keywords: Iron iron oxides, α-Fe2O3, chemical polyol methods, heat treatment.

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Submicrometer-sized Spherical Iron Oxide Particles Fabricated by Pulsed Laser Melting in Liquid

IEEJ Transactions on Electronics Information and Systems ◽

10.1541/ieejeiss.135.1066 ◽

2015 ◽

Vol 135 (9) ◽

pp. 1066-1070

Author(s):

Yoshie Ishikawa ◽

Naoto Koshizaki ◽

Alexander Pyatenko

Keyword(s):

Iron Oxide ◽

Pulsed Laser ◽

Iron Oxide Particles ◽

Laser Melting ◽

Oxide Particles

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Aqueous one-pot synthesis of well-defined zwitterionic diblock copolymers by RAFT polymerization: an efficient and environmentally-friendly route to a useful dispersant for aqueous pigments

Green Chemistry ◽

10.1039/d0gc04271d ◽

2021 ◽

Vol 23 (3) ◽

pp. 1248-1258

Author(s):

Shannon M. North ◽

Steven P. Armes

Keyword(s):

Iron Oxide ◽

Diblock Copolymers ◽

Raft Polymerization ◽

Environmentally Friendly ◽

Iron Oxide Particles ◽

One Pot ◽

One Pot Synthesis ◽

Highly Effective ◽

Oxide Particles

An atom-efficient, wholly aqueous one-pot synthesis of zwitterionic diblock copolymers has been devised. Such copolymers can serve as highly effective aqueous dispersants for nano-sized transparent yellow iron oxide particles.

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