硫化镉复合二氧化钛纳米管阵列光电化学研究

Photoelectrochemical properties of CdS-TiO_2 heterojunction nanocomposites

采用阳极氧化法在钛片表面制备出了内径约70 nm,管壁厚度约30 nm的整齐有序的TiO_2纳米管列阵,而后通过浸渍法得到Cd S复合的TiO_2纳米管阵列。XRD和SEM分析样品晶型以及形貌特征的结果表明,随着浸渍次数的增加,TiO_2纳米管阵列上复合的CdS的量也随之增加。利用电化学工作站测定样品光电转化性能,结果表明,在TiO_2纳米管阵列上适量地复合CdS可以有效提高其光电转化效率,并且在浸渍次数为2次时,复合TiO_2纳米管阵列具有最佳光电化学性能,与纯二氧化钛纳米管的光电流为0.26 m A/cm^2,太阳光转化率为0.95%相比较,其光电流可达到0.58 m A/cm^2,太阳光转化率可达到4.02%,分别高于纯二氧化钛纳米管的2倍和4倍。

Ordered TiO_2 nanotube arrays were prepared by anodic oxidation method on pure titanium foil,Then Cd S were successfully composited with TiO_2 nanotube arrays by impregnation method. They were characterized by X-ray diffraction,scanning electron microscopy and electrochemical test. The results showed that the TiO_2 nanotube arrays owing a diameter of 70 nm,wall thickness of 30 nm. With the increase of impregnation times,the amount of CdS on the TiO_2 nanotube arrays is increased. Great improvement of photoelectrochemical conversion efficiency for TiO_2 nanotube arrays can be achieved by the proper combination of CdS. Obtaining an optimum deposition Cd S for 2 times,its photocurrent reached0. 58 m A/cm^2,photoconversion rate 4. 02%,which is more than 2 times and 4 times to pure TiO_2 at photocurrent 0. 26 m A/cm^2,photo conversion rate 0. 95%.