Thermal Decomposition Synthesis of Iron Oxide Nanoparticles with Diminished Magnetic Dead Layer by Controlled Addition of Oxygen.
Decades of research focused on size and shape control of iron oxide nanoparticles have led to methods of synthesis that afford excellent control over physical size and shape but comparatively poor control over magnetic properties. Popular synthesis methods based on thermal decomposition of organometallic precursors in the absence of oxygen have yielded particles with mixed iron oxide phases, crystal defects, and poorer than expected magnetic properties, including the existence of a thick "magnetically dead layer" experimentally evidenced by a magnetic diameter significantly smaller than the physical diameter. Here, we show how single-crystalline iron oxide nanoparticles with few defects and similar physical and magetic diameter distributions can be obtained by introducing molecular oxygen as one of the reactive species in the thermal decomposition synthesis. This is achieved without the need for any postsynthesis oxidation or thermal annealing. These results address a significant challenge in the synthesis of nanoparticles with predictable magnetic properties and could lead to advances in applications of magnetic nanoparticles.
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Mythreyi
M
Unni
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Amanda M
AM
Uhl
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Shehaab
S
Savliwala
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Benjamin H
BH
Savitzky
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Rohan
R
Dhavalikar
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Nicolas
N
Garraud
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
David P
DP
Arnold
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Lena F
LF
Kourkoutis
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Jennifer S
JS
Andrew
Department of Chemical Engineering, ‡Department of Materials Science and Engineering, §Interdisciplinary Microsystems Group, Department of Electrical and Computer Engineering, and ⊥J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida , Gainesville, Florida 32611, United States.|Department of Physics, #Applied & Engineering Physics, and ¶Kavli Institute at Cornell for Nanoscale Science, Cornell University , Ithaca, New York 14853, United States.
Carlos
0000-0001-8886-5612
C
Rinaldi
iron oxide; magnetic dead layer; magnetic diameter; magnetic nanoparticles; oxygen; thermal decomposition