Surfactants Removal Process and Bulk Samples Preparation

7 Surfactants Removal Process and Bulk Samples Preparation 

The organic surfactants were removed via the procedure of previously reports [2] before fabrication of bulk samples for thermoelectric measurement. Briefly, as-prepared silver chalcogenides were dispersed in cyclohexane with hydrazine solution (85 % v/v) and stirred vigorously until all the nanocrystals precipitated. The supernatant is decanted and the precipitate is washed with ethanol three to four times to remove hydrazine and collected by centrifugation, and then dried in vacuum at 65 °C. After the hydrazine treatment, the nanocrystals are hot-pressed into rectangular (10 mm x 4 mm x 1.5 mm) and round disk bulk samples (with diameter of about 13 mm and thickness of 2 mm) under 60 MPa at 400 for 30 min. 

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