Doping potassium niobate with transition metals enhances its photocatalytic properties
Doping potassium niobate with transition metals enhances its photocatalytic properties lead image
Materials that photocatalytically split water are highly sought after for their potential for green energy and curbing environmental pollution. Potassium niobate is often overlooked for this use due to its large bandgap. Doping the material with semiconductors, however, may provide a path forward.
Maarouf et al. report results from a set of first-principles calculations that describe how changes in the electronic and optical properties of potassium niobate doped with 3d and 4d transition metals at the niobate ion site enhance its photocatalytic behavior. Such an approach reduces the material’s bandgap by pinning a dopant level near the top and bottom of the conduction band.
The paper marks an early demonstration of the power of doping to optimize otherwise overlooked materials for environmental engineering.
“Our paper sheds light on the potential of doped potassium niobate for use in green energy applications, thus opening a door for researchers to employ these materials in many applications,” said author Mohamed Fadlallah.
They demonstrated that substituting out niobate ions with transition metals decreased the bandgap and improved the optical and photocatalytic activity of potassium niobate.
Among the dopants they calculated, silver- and manganese-doped potassium niobate proved to be the best candidates for water splitting and carbon dioxide reduction.
In addition to finding potential new photocatalytics, the group’s approach also found that doping the potassium niobate with technetium showed promising properties for spintronics.
Fadlallah and the group hope their work sparks more interest in doping cubic perovskites like potassium niobate for photocatalysis. They look to use their calculations as a jumping board into experimental studies to confirm and further characterize their findings.
Source: “Metal doped KNbO3 for visible light photocatalytic water splitting: A first principles investigation,” by Ahmed A. Maarouf, D. Gogova, and Mohamed M. Fadlallah, Applied Physics Letters (2021). The article can be accessed at https://doi.org/10.1063/5.0058065 .
