Controllable synthesis of X-shaped flowerlike PbTe microcrystals via a simple hydrothermal process

In the present paper, we successfully prepared X-shaped flowerlike PbTe microcrystals in a simple aqueous system via the hydrothermal route employing PbO, Te powders and NaH2PO2·H2O as the starting reactants at 150 °C for 14 h. Some factors affecting the morphology of PbTe microcrystals, such as the reaction temperature, time, the amount of NaOH, sorts of reductants, and reaction solvents, were systematically investigated. Experimental results indicated that NaH2PO2·H2O played a crucial role in the formation of X-shaped flowerlike PbTe microcrystals. Temperature and time were also important factors affecting the formation of PbTe microcrystals with X-shaped flowers: the lower temperature or shorter time did not avail to obtain products with X-shaped flowers while keeping the other experimental conditions constant. A possible formation mechanism of PbTe microcrystals was proposed based on the experimental results.