We report a self-organized copper electrodeposition without imposed templates and induced additives. The deposit morphology on the silicon substrate varies from a branch to a parallel pattern by changing the applied voltage. We suggest that there are two essential factors for the formation of such kind of copper wire arrays. One is a proper electric potential distribution near the tip of the copper wire which dictates the direction of the solute transport. The other one is that the cathode overpotential and the equilibrium potential of reaction should remain unchanged at the growing interface.

Near single phase ternary bulk thermoelectric material AgSbTe2 was synthesized by high pressure and high temperature (HPHT) method. The temperature-dependent thermoelectric properties including Seebeck coefficient, electrical conductivity, and thermal conductivity were studied. The HPHT synthesized AgSbTe2 sample has higher thermoelectric performance in the measured temperature range than that of the same sample prepared at normal pressure. The enhanced thermoelectric properties should be attributed to the HPHT quenching which keeps partially the high electrical conductivity of AgSbTe2 under high pressure.

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