Dear altruists, thanks in advance. I have been trying to synthesize MFe2O4 (M= Ni, Co...etc.) type ferrites in sol-gel method. As described in several papers, pH of the citric acid and metal nitrate solution plays a key role in the size of the nano-particles. Most of which suggests to keep the pH level at 7 mixing Ammonia solution. But the problem is whenever nitrates are mixed in de-ionized water the pH gets reduced to 0.4~0.6 and mixing ammonia soln increases the value but not more than 2/3. How can i solve this problem?