形貌和光催化性能的影响
(1. 哈尔滨工业大学 深圳研究生院，材料科学与工程学科部，深圳 518055；
2. 中南大学 粉末冶金国家重点实验室，长沙 410083；
3. 哈尔滨工业大学 深圳研究生院 城市与土木工程学科部，深圳 518055)
摘 要: 分别以0.5%HF水溶液(A)、0.3 mol/L NH4F+70% H2O+30%甲酰胺(体积分数)(B)、0.3 mol/L NH4F+30% H2O+70%甲酰胺(体积分数)(C)和0.3 mol/L NH4F+3% H2O+97%甲酰胺溶液电解液(体积分数)(D)作为电解液，对比研究甲酰胺含量对电化学阳极氧化TiO2纳米管阵列的形貌、结构和光催化性能的影响。结果表明： TiO2纳米管阵列长度随甲酰胺含量的增加而增加；水基电解液A中制备的纳米管长度、壁厚和管径分别约为600、20和100 nm，且分布不均匀；甲酰胺基电解液D中制备的纳米管长度、壁厚和管径分别约为10 μm、5 nm和60 nm，且管径分布均匀；样品在O2中经450 ℃退火2 h后，发现甲酰胺基电解液A中制备的TiO2纳米管为单相锐钛矿结构，其它样品则为复合锐钛矿相和金红石相结构。光催化降解甲基橙的结果表明：随着TiO2纳米管阵列的厚度增加及管壁减小，紫外光光催化效率明显提高。
关键字: 电化学阳极氧化；电解液；TiO2纳米管；光催化
photocatalytic activity of TiO2 nanotube arrays by anodization
（1. Division of Materials Science and Engineering, Shenzhen Graduate School, Harbin Institute of Technology,
Shenzhen 518055, China;
2. State Key Laboratory for Powder Metallurgy, Central South University, Changsha 410083, China;
3. Division of Urban and Civil Engineering, Shenzhen Graduate School, Harbin Institute of Technology,
Shenzhen 518055, China）
Abstract:The influence of the fomamide concentration in the electrolytes on the morphology and structure was investigated in the electrolytes of 0.5%HF water solution (A), 0.3 mol/L NH4F+70%H2O+30% formamide (volume fraction) (B), 0.3% mol/L NH4F+30%H2O+70% formamide (volume fraction) (C) and 0.3 mol/L NH4F+3%H2O+97% formamide (volume fraction) (D). The nanotube becomes long and its wall thickness becomes smaller with increasing formamide concentration in electrolyte. The results show that the nanotube becomes longer and its wall thickness becomes smaller with increasing formamide concentration in electrolyte. The tube length, pore diameter and wall thickness of TiO2 nanotube arrays anodized in water-based electrolyte A are about 600 nm, 100 nm and 5 nm, respectively. The tube length, wall thickness and pore diameter for sample anodized in formamide-based electrolyte D are about 10 μm, 5 nm and 60 nm, respectively. After being annealed at 450 ℃ for 2 h in oxygen, the single anatase structure is obtained for sample anodized in electrolyte A. In contrast, the mixed anatase and rutile phase are observed in TiO2 nanotube for the other three samples. The results of photodegradation of methyl orange (MO) show that TiO2 nanotubes with longer tube length and thinner wall thickness have higher photocatalytic activity.
Key words: electrochemical anodization; electrolyte; TiO2 annotube; photocatalytic
