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Monodisperse, colloidally stable, sub-3 nm europium sesquioxide (Eu2O3), terbium sesquioxide (Tb2O3), and Eu3+-doped gadolinium sesquioxide (Gd2O3:Eu3+) nanocrystals have been synthesized via a hot solution-phase technique. The oleic acid concentration facilitated the production of the nanocrystals in a range of sizes from sub-2 nm up to 5.0 nm. The Eu2O3 and Gd2O3:Eu3+ nanocrystals exhibit new luminescence peaks at 620 nm, which correspond to modulation of the 7F2 transition of the Eu3+ ion. The Tb2O3 nanocrystals express a new luminescence feature at 548 nm, which corresponds to modulation of the 7F5 transition of the Tb3+ ion.

Alternating layer, carbon nanotubes-nanocrystal composite films, comprising multi-walled carbon nanotubes (MWCNTs) and iron oxide (Fe(3)O(4)) nanocrystals, have been fabricated via electrophoretic deposition (EPD) on stainless steel and gold substrates. Low field-high current and high field-low current EPD schemes were integrated to produce the composite films. The low field-high current EPD approach produced porous mats from an aqueous suspension of the MWCNTs, while the high field-low current EPD approach produced tightly packed nanocrystal films from a dispersion of the nanocrystals in hexane. Large electric fields applied during the nanocrystal EPD and strong van der Waals interactions among the nanocrystals facilitated the formation of tightly packed nanocrystal films atop the MWCNT mats to create CNT mat-nanocrystal film composites. The surface coverage and homogeneity of the nanocrystal films improved with repeated deposition of the nanocrystals on the same mat. The assembly of nanotube mats on top of the CNT mat-nanocrystal film composite confirmed the feasibility of multilayered CNT mat-nanocrystal film heterostructures suitable for a range of devices. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) techniques were employed to characterize the surface coverage, homogeneity, and topology of these composite films.

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