摘要 探讨了酸度对直接沉淀法合成钛酸钡的影响及其作用机理。结果表明，反应体系的pH必须大于13才能在一定能量场的作用下形成钛酸钡。反应过程中OH－所起的作用不仅是简单的中和，关键是促使体系中形成活泼的H4TiO4以及Ba(OH)2等形式，并使之产生良好的共沉淀或吸附；而且在形成[TiO6]八面体以及H4TiO4与Ba(OH)2反应的过程中都起了重要的促进作用。
关键词 酸度 钛酸钡 直接沉淀法
Effect of pH VALUE on FORMATION of BaTiO3 by Direct Precipitation Method
WANG Jing 1, DONG Sainan1, LUAN Xuemei1, SHANG Shaoming1,2
(1 School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122; 2 School of Chemical Engineering, Nanjing University of Science & Technology, Nanjing 210094)
Abstract The effect of the pH value on the formation of BaTiO3 by the direct precipitation method and its mechanisms are discussed. The experimental results show that only when pH >13 can BaTiO3 be formed at a certain energy field. As for the influence of OH, it's obvious that it's not simply neutralization, it's favorable to form active H4TiO4 and Ba(OH)2or other active forms in the system and stimulate them to have coprecipitation and adsorption easily. It also plays a vital role in the formation of octahedral [TiO6] and the reaction of H4TiO4 with Ba(OH)2.
Keywords barium titanate, direct precipitation, pH value