Role Of pH In the Pure Phase Formation of Barium Stannate Nanostructure Via Chemical Precipitation Route

Mobility of a TCO (transparent conducting oxide) depends on purity of phase, temperature and effective mass of charge carriers. Phase purity and operating temperature are the two controllable parameters to enhance the mobility. In this study firstly we have analyzed the role of pH on pure phase formation of BaSnO3 by using two different bases NaOH and NH3. For this, the experiment is performed at various pH values i.e. from pH-8 to pH-11 using NH3. Secondly at pH -11 the chemical precipitation synthesis was performed by using Base NaOH and chlorides as precursor. It is observed that Pure phase formation of stannate nanostructure i.e. BaSnO3 through Chemical precipitation is very much controlled by pH of the precursor solution. The pH affects the solubility of a compound and thus further decides the precipitation of desired hydroxides of metals. In this study pure phase formation was analyzed through XRD studies. It is evident through our studies that in chemical synthesis of BaSnO3, NaOH is better choice of base than NH3. Also, Barium Chloride is better precursor than Barium carbonate in synthesizing BaSnO3 nanostructures. XRD study also revealed that while using Barium carbonate, SnO2 phase appeared as impurity but when Barium chloride is used, no such impurity is observed. SEM studies revealed the micro rod like morphology of Barium stannate. The RT mobility of these Barium stannate microrods comes out to be 49 cm2/V-sec.