A New Family of Plasmonic Photocatalysts without Noble Metals

Efficient photocatalysis is important for sustainable energy. Recently, an unconventional photocatalyst based on intrinsic plasmon, called intrinsic plasmonic photocatalyst (IPP), seems promising for higher efficiency in hydrogen evolution¹. This catalyst seems to benefit from the advantages of visible light absorption, plasmon-assisted hot carrier generation over conventional photocatalysts. Here, we report the relative hydrogen evolution efficiency under visible light irradiation of a family of IPP based on alkaline earth niobates (MNbO₃ , where M=Ca, Sr or Ba), with efficiency of CaNbO₃ > SrNbO₃ > BaNbO₃. The contributions of electron-phonon coupling time and solar energy absorption to the hydrogen evolution efficiency are identfied as keys based on our comprehensive characterization of carrier density (10²² cm^-3), plasmon absorption, carrier dynamics and surface area. This study demonstrates a generic approach to create a family of IPP and validates the solar energy absorption of intrinsic plasmon as an additional knob to enchance the photocatalytic efficiency.
1. D.Y. Wan, Y.L. Zhao, Y. Cai,et al., Nature Communications 8, 15070 (2017)