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Vanadium boride seeded YB 22 C 2 N were synthesized and the thermoelectric properties investigated. YB 22 C 2 N is representative of the series of rare earth borocarbonitrides which is the potential long awaited n-type counterpart to p-type boron carbide. VB 2 seeded samples of YB 22 C 2 N were prepared using VB 2 directly as an initial additive and V 2 O 3 which also results in formation of vanadium diboride in the final product. The resistivity and Seebeck coefficient of samples were measured in the temperature range of 323 K to 1073 K. A dramatic effect of thermal treatment on the Seebeck coefficient of VB 2 seeded samples was observed, and it is indicated that there is possible partial intrinsic doping of vanadium into YB 22 C 2 N. VB 2 is revealed to be a promising additive to improve the thermoelectric properties of YB 22 C 2 N. An enhancement of more than 220% of the maximum absolute value of the Seebeck coefficient was obtained while the resistivity was also reduced considerably.

High quality CeB 6 thin films have been obtained through direct evaporation of raw micron-sized CeB 6 powders at a pressure of 70 Pa. The X-ray diffraction (XRD), Raman spectrum, scanning electron microscope (SEM), transmission electron microscopy (TEM), selected-area electron diffraction (SAED) and the field-emission equipment were used to characterize the morphology, structure, composition and FE properties of the samples. The XRD and Raman spectrum analysis results show the as-prepared product is cubic phase CeB 6 . The TEM, SAED and HRTEM analysis reveal that the samples are mixtures of thin films (polycrystalline) and small crystals (single crystallines aligned preferentially in the [1 1 0] direction). Compared to oxide nanostructures, field-emission measurements show that the CeB 6 films have better FE performance with turn-on field and threshold field of 12.93 V/μm and 14.86 V/μm, respectively.