Abstract：
The manganese-cobalt mixed oxide nanorods were fabricated using a hydrothermal method with different metal precursors (KMnO4 and MnSO4·H2O for MnOx and Co(NO3)2⋅6H2O and CoCl2⋅6H2O for Co3O4). Bamboo-like MnO2⋅Co3O4 (B-MnO2⋅Co3O4 (S)) was derived from repeated hydrothermal treatments with Co3O4@MnO2 and MnSO4⋅H2O, whereas Co3O4@MnO2 nanorods were derived from hydrothermal treatment with Co3O4 nanorods and KMnO4. The study shows that manganese oxide was tetragonal, while the cobalt oxide was found to be cubic in the crystalline arrangement. Mn surface ions were present in multiple oxidation states (e.g., Mn4+ and Mn3+) and surface oxygen deficiencies. The content of adsorbed oxygen species and reducibility at low temperature declined in the sequence of B-MnO2⋅Co3O4 (S) > Co3O4@MnO2 > MnO2 > Co3O4, matching the changing trend in activity. Among all the samples, B-MnO2⋅Co3O4 (S) showed the preeminent catalytic performance for the oxidation of toluene (T10% = 187°C, T50% = 276°C, and T90% = 339°C). In addition, the B-MnO2⋅Co3O4 (S) sample also exhibited good H2O-, CO2-, and SO2-resistant performance. The good catalytic performance of B-MnO2⋅Co3O4 (S) is due to the high concentration of adsorbed oxygen species and good reducibility at low temperature. Toluene oxidation over B-MnO2⋅Co3O4 (S) proceeds through the adsorption of O2 and toluene to form O*, OH*, and H2C(C6H5)* species, which then react to produce benzyl alcohol, benzoic acid, and benzaldehyde, ultimately converting to CO2 and H2O. The findings suggest that B-MnO2⋅Co3O4 (S) has promising potential for use as an effective catalyst in practical applications.
摘要：
锰钴混合氧化物纳米棒是使用水热法使用不同的金属前体（MnOx的KMnO4和MnSO4·H2O和Co3O4的Co（NO3）2·6H2O和CoCl2·6H2O）制造的。竹状的MnO2·Co3O4（B-MnO2·Co3O4（S））来自Co3O4@MnO2和MnSO4·H2O的重复水热处理，而Co3O4@MnO2纳米棒来自Co3O4纳米棒和KMnO4的水热处理。研究表明，氧化锰是四方的，而发现氧化钴在结晶排列中是立方的。Mn表面离子以多种氧化态存在(例如，Mn4+和Mn3+)和表面氧缺乏。吸附氧的含量和低温还原性以B-MnO2·Co3O4（S）>Co3O4@MnO2>MnO2>Co3O4的顺序下降，与活性的变化趋势相匹配。在所有样本中，B-MnO2·Co3O4（S）对甲苯的氧化表现出卓越的催化性能（T10％=187°C，T50%=276°C,和T90%=339°C)。此外,B-MnO2·Co3O4(S)样品也表现出良好的H2O-，CO2-,和耐SO2性能。B-MnO2·Co3O4（S）的良好催化性能是由于高浓度的吸附氧物种和良好的低温还原性。B-MnO2·Co3O4（S）上的甲苯氧化通过吸附O2和甲苯形成O*进行，OH*,和H2C（C6H5）*物种，然后反应产生苯甲醇，苯甲酸,和苯甲醛，最终转化为CO2和H2O。研究结果表明，B-MnO2·Co3O4（S）具有在实际应用中用作有效催化剂的潜力。
