TiO_(2)@C核壳纳米棒薄膜光阳极的制备及其光电催化性能研究

Preparation of TiO_(2)@C Core-shell Nanorods Photoanodes for Photoelectrochemical Water Splitting

以钛酸四正丁酯(TBT)为钛源,以葡萄糖(C_(6)H_(6)O_(6))为碳源,采用二次水热法和热处理在FTO导电玻璃上原位生长了表面包覆超薄碳层的TiO_(2)@C核壳纳米棒薄膜光阳极。利用XRD、SEM、TEM、XPS、FT-IR、UV-vis、Raman、PL对制备的样品进行表征和测试,最后采用电化学三电极法对样品进行光电转化性能测试。结果表明,实验成功制备了TiO_(2)纳米棒薄膜,单根纳米棒尺寸为100~200 nm,复合样品表面均匀生长了一层C,形成了TiO_(2)@C核壳纳米棒阵列结构,与纯的TiO_(2)相比复合材料表现出更好的光催化性能。其中,最优C 6H 6O 6浓度为4 mmol/L,该浓度下制备的TiO_(2)@C在1.23 V vs.RHE时的光电流密度为1.65 mA/cm^(2),是纯TiO_(2)光电流密度大小的1.39倍。TiO_(2)@C核壳纳米棒薄膜光阳极的光催化性能得到了很大的提升。这是由于C层修饰了TiO_(2)的表界面,而C自身良好的导电性也促进了电子-空穴的分离和转移,提高了光生载流子的寿命,从而使其光电转化性能明显提升。

TiO_(2)@C core-shell nanorods photoanodes were prepared via a two-step hydrothermal method and heat treatment,using tetra-n-butyl titanate(TBT)as titanium source and glucose(C_(6)H_(6)O_(6))as carbon source.The samples were characterized by XRD,SEM,TEM,XPS,FT-IR,UV-vis,Raman and PL.The photoelectro-chemical properties of these prepared photoelectrodes were tested by three electrode method.The results showed that TiO_(2) nanorods were successfully prepared,the size of single nanorods was 100-200 nm.C was uniformly grown on the surface of the TiO_(2),and TiO_(2)@C core-shell nanorods array structure formed.Compared with pure TiO_(2) array,TiO_(2)@C showed better photoelectrochemical properties.The optimal glucose concentration is 4 mmol/L,and the photocurrent density of TiO_(2)@C is 1.65 mA/cm^(2),which is 1.39 times of that of pure TiO_(2).After modification of C layer,the photocurrent density of TiO_(2)@C is greatly improved by simultaneously promoting the photo-generated charge separation and surface reaction transfer.