论文标题
UPS和UV光谱镜结合到位于TiO2剖析酶和金红石纳米植物的能量水平
UPS and UV spectroscopies combined to position energy levels of TiO2 anatase and rutile nanopowders
论文作者
论文摘要
半导体纳米植物中电子结构的准确测定是一项艰巨的任务。我们在这里建议将UPS和UV-VIS光谱镜结合起来，以便完整描述粉末样品TiO2金红石和剖果酶的电子带对齐。对于UPS测量，使用两种制备方法，即掉落方法和电泳沉积，用于在导电底物，ITO或AG上制备二氧化钛粉末层。两种方法都会取得可比的结果，并定量描述价带的能级。将这些结果与相同粉末的UV-VIS光谱相结合，使能够确定价带最大值的绝对位置和最小传导带的绝对位置。联合UPS - UV-VIS光谱法提供了对粉末状材料的性质的更好洞察力，这可能与单晶模型系统不同。在光催化过程中，它也可用于预测混合相系统中的电子传输。
An accurate experimental determination of electronic structure in semi-conductors nanopowders is a challenging task. We propose here to combine UPS and UV-Vis spectroscopies in order to get the full description of electronic bands alignment of powder samples, TiO2 rutile and anatase. For UPS measurements, two preparation methods, namely dropping method and electrophoretic deposition, were used to prepare layers of titania powders on a conducting substrate, ITO or Ag. Both methods lead to comparable results, with a quantitative description of the energy levels from the valence band. Combining these results with the UV-Vis spectra of the same powders, enables to determine the absolute position of the valence band maximum and of the conduction band minimum. Combined UPS--UV-vis spectroscopy provides a better insight into the properties of a powdered material which can differ from single crystal model systems. It can be also used to predict the electronic transfer in mixed phase systems during, in photocatalytic processes.
