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Abstract: alloying is an effective way to manipulate the composition and physico-chemical properties of functional materials. We demonstrated the syntheses of alloyed Co_xNi_1−xO nanocrystals using a nonaqueous approach, with x continuously tuned from 0 to 1 by varying the molar ratios of the cobalt precursor in the reagents. The morphological, structural, and compositional properties of the alloyed Co_xNi_1−xO nanocrystals were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and energy dispersive X-ray spectroscopy (EDS). The results showed that the cobalt and nickel atoms were homogeneously distributed in the alloyed nanocrystals. The as-prepared Co_xNi_1−xO nanocrystals can be applied as the hole-transporting layers in polymer light emitting diodes (PLEDs). Our study provides a good example for the syntheses of alloyed oxide nanocrystals with continuously tunable composition.

This manuscript reports the syntheses of alloyed CoxNi1-xO nanocrystals by the protecting-ligand assisted approach, with x can be tuned from 0 to 1. The authors conducted detailed characterizations and provided solid evidences on the formation of alloyed nanocrystals. This work is of interest for the material scientists and chemists working in the field of colloidal nanocrystals.

Co_xNi_1-xO合金纳米晶的合成与表征

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