采用水热法,以In(OH),为前驱物,纯水或添加1mol/L KOH和5mol/L KOH分别作矿化剂,填充度为35%,分别在200℃、250℃和350℃条件下反应24h合成了In(OH)3、InOOH和In2O3晶体。研究了在不同温度和使用不同矿化剂时,In(OH)3、InOOH、In2O3相转化规律,并对它们的形貌进行了分析。实验发现:在纯水条件下,200℃时,In(OH),未发生晶相转化和明显的二次结晶过程,晶体无特定形貌;在250℃、350℃时,晶体转化为InOOH。当矿化剂浓度为1mol/LKOH和5mol/LKOH,温度为200℃时,In(OH),晶体出现了二次晶化,特别是在5mol/LKOH时,最大晶体尺度达到20μm,最小晶体仅为200nm;当温度达到250℃时,生成InOOH晶体和少量In2O3超过350℃,水热反应生成立方铁锰矿相In2O3,晶体边长超过50μm,显露{001}、{010}、{100}以及{101}等晶面。
In(OH)3, InOOH and In2O3 crystals were synthesized by hydrothermal method, using pure water, 1 mol/L KOH and 5 mol/L KOH as mineralizer, the fill factor of 35%, reacted at the temperature of 200 ℃, 250 ℃ and 350 ℃ respectively, and time of 24 h. The phase transformation rule of In (OH) 3,InOOH and In2O3 was studied in different temperatures and mineralizer, and their morphology have been analyzed. When pure water was used, temperature was 200 ℃, the results showed that In (OH) 3 crystalline phase was no obvious transformation and secondary crystallization, the crystal had non- specific morphology. While temperature was 250 ℃ and 350 ℃, the In (OH)3 crystal transformed into InOOH. When 1 mol/L KOH and 5 mol/L KOH was used, temperature was 200 ℃ , the In (OH) 3 crystal had secondary crystallization. In particular, the largest-scale crystal was about 20 p.m, the smallest crystal was less than 200 nm when 5 mol/L KOH was used. InOOH crystal and a small amount of In203 were obtained in 250 ℃. When temperature reached 350 ℃, the In203 with cubic bixbyite structure was obtained, exposing the faces {001 }, {010}, {100} and { 101} side was more than 50 p.m.