MOF-Templated Metal Oxides Sensitized with Quantum Dots Heterojunction for Efficient Solar Fuels Generation

摘要

The separation and transport of photogenerated charges carriers are two of the most crucial factors that determine the overall efficiency of photoelectrochemical (PEC) systems. Various strategies have been exploited for achieving efficient charge separation and transfer. Among them, the design of semiconductor heterojunction has been shown to be one of the most effective approaches. Metal oxides, such as TiO_2, are the among the most common materials for water splitting. However, the control of phase alignment and the interface structure remains a challenge. A promising solution is to use a template approach by employing metal-organic frameworks (MOF) which are of broad interest as a new class of organic-inorganic hybrid materials and have been intensely exploited in various fields due to their unique physical and chemical properties. Furthermore, common metal oxides, such TiO_2 or NiO have limited absorption of sunlight due to their large intrinsic band gap (i.e. TiO_2 anatase: 3.2 eV) which hinders effective use in solar water splitting. To extend the absorption range of the MOF-templated metal oxides in the visible and near-infrared range, we employed metal chalcogenide QDs as sensitizers.