论文标题
赤铁矿光阳极的波长依赖性光电流：重新评估孔收集长度
Wavelength Dependent Photocurrent of Hematite Photoanodes: Reassessing the Hole Collection Length
论文作者
论文摘要
平面1 CM2厚的Ti掺杂的赤铁矿膜的光电化学行为沉积在F：SNO2涂层玻璃上，并用前后照明研究了。尽管量子效率低，但在带有低波长的背部照明时仍观察到光电流，这表明某些光生孔能够在赤铁矿膜中至少遍历至少700 nm，并有效地氧化水。这不能考虑使用基于与Gartner模型的拟合使用的赤铁矿的常见孔收集长度。此外，在背部照明下，450 nm的激发导致光电流增加，而530 nm激发，尽管大多数光被吸收到远离表面。这些结果表明，光电流很大程度上取决于光激发波长，并且与具有长寿命和局部激发的离域孔相关，而不仅仅取决于吸收与表面的接近度。
The photoelectrochemical behavior of a planar 1 cm2 thick Ti-doped hematite film deposited on F:SnO2 coated glass was studied with both front and back illumination. Despite low quantum efficiency, photocurrent was observed upon back illumination with low wavelengths, indicating that some photogenerated holes are able to traverse at least 700 nm across the hematite film and effectively oxidize water. This cannot be accounted for using the commonly accepted hole collection length of hematite based on fitting to the Gartner model. Furthermore, under back illumination, 450 nm excitation resulted in increased photocurrent as compared to 530 nm excitation despite most of the light being absorbed further away from the surface. These results demonstrate that the photocurrent is strongly dependent on the optical excitation wavelength, and related to both delocalized holes with long lifetime and localized excitations rather than only being dependent on the proximity of the absorption to the surface.
