α-/β-MnO_2的水热合成及其催化性能  

Synthesis and Catalytic Performance of α-/β-MnO_2 Nanorods

作　　者：杨则恒[1] 宋欣民[1] 张卫新[1] 王华[1] 汪芳[1] 

机构地区：[1]合肥工业大学化工学院,合肥230009

出　　处：《应用化学》2008年第1期13-16,共4页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(20576024);安徽省自然科学基金(070414165)资助项目

摘　　要：以KMnO4为锰源，抗坏血酸为还原剂，通过水热法于相同的反应体系分别合成了α-MnO2和β-MnO2纳米棒，采用XRD和TEM测试技术对合成产物进行了表征。结果表明，在抗坏血酸与KMnO4摩尔比为1：5的酸性水热反应体系中，反应温度和时间是影响合成产物的重要因素。存150～160℃反应12h得到α-MnO2纳米棒，而在170℃反应24h则得到β-MnO2纳米棒。以酸性品红（FA）为模拟污染物评估了所制备MnO2样品的催化活性。结果显示，α-MnO2和β-MnO2纳米棒对H2O2氧化降解酸性品红均有良好的催化活性，且催化性能明显优于相应的块体材料。其中，β-MnO2纳米棒的催化活性最高，反应60min酸性品红脱色率即达到97.6％。α- and/β-MnO2 nanorods were successfully prepared by a hydrothermal method based on the redox reaction of KMnO4 and ascorbic acid（AA）. XRD, TEM techniques were used to characterize the as-prepared MnO2 samples. The results indicated that reaction temperature and reaction time were the key factors to determine the crystallographic forms of the final products from the hydrothermal system, in which the molar ratio of AA to KMnO4 was 1：5. α-MnO2 nanorods were obtained when the reaction was conducted at 150 -160 ℃ for 12 h, while β-MnO2 nanorods were prepared at 170 ℃ for 24 h. The catalytic activities of the as-prepared MnO2 nanorods and commercial MnO2 were evaluated by minitoring the degradation of fuchsin acid in the presence of H2O2. Both α- and /β-MnO2 nanorods exhibited higher catalytic activity on the degradation of fuchsin acid than bulk MnO2. β-MnO2 had the highest activity among the three, resulting in 97.6% decoloration of the fuchsin acid solution within 60 minutes.

关 键 词：水热法 纳米MNO2 酸性品红 催化活性 

分 类 号：O611.4[理学—无机化学] O643.3[理学—化学]