Phase‐pure [NiO]0.5[Al2O3]0.5spinel nanoparticles (NPs) with limited aggregation were obtained via liquid‐feed flame spray pyrolysis (LF‐FSP) by combusting metalloorganic precursor solutions. Thereafter “chocolate chip‐like” Nix[NiO0.5‐x][Al2O3]0.5nanoparticles consisting of primary [NiO0.5‐x][Al2O3]0.5particles with average particle sizes of 40‐60 nm decorated with Ni metal particles (<10 nm in diameter) dispersed on the surface were synthesized by heat treating the spinel NPs at 800°C/7 h in flowing 5% H2:N2100 mL/min in a fluidized bed reactor. The synthesized materials were characterized using TEM, XRD, FTIR, and TGA/DTA. The Ni depleted areas consist primarily of γ‐Al2O3. The Ni content (800°C) was determined by TGA to be ≈11.3 wt.% based on TGA oxidation behavior. The successful synthesis of such nanocomposites with limited aggregation on a high temperature support provides a facile route to synthesize well‐defined NP catalysts. This work serves as a baseline study for an accompanying paper, wherein thin, flexible, dense films made from these same NPs are used as regenerable catalysts for carbon nanotube syntheses.
Synthesis and dielectric properties of nanocrystalline oxide perovskites, [KNbO 3 ] 1−x [BaNi 0.5 Nb 0.5 O 3−δ ] x , derived from potassium niobate KNbO 3 by gel collection
- Award ID(s):
- 1461499
- NSF-PAR ID:
- 10024447
- Date Published:
- Journal Name:
- J. Mater. Chem. C
- Volume:
- 4
- Issue:
- 34
- ISSN:
- 2050-7526
- Page Range / eLocation ID:
- 7989 to 7998
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract -
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C6TC02327D
