Exciton-like trap states limit electron mobility in TiO2 nanotubes
Source abstract
Abstract
Nanoparticle films have become a promising low-cost, high-surface-area electrode material for solar cells and solar fuel production. Compared to sintered nanoparticle films, oriented polycrystalline titania nanotubes offer the advantage of directed electron transport, and are expected to have higher electron mobility. However, macroscopic measurements have revealed their electron mobility to be as low as that of nanoparticle films. Here, we show, through time-resolved terahertz spectroscopy, that low mobility in polycrystalline TiO(2) nanotubes is not due to scattering from grain boundaries or disorder-induced localization as in other nanomaterials, but instead results from a single sharp resonance arising from exciton-like trap states. If the number of these states can be lowered, this could lead to improved electron transport in titania nanotubes and significantly better solar cell performance.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Quantum Dots Synthesis And Properties · Chalcogenide Semiconductor Thin Films · Advanced Photocatalysis Techniques
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (35)
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