Fabrication, Characterization, and Photoelectrochemical Properties of Cu‐Doped PbTiO3 and Its Hydrogen Production Activity

Abstract We report herein the fabrication of visible‐light responsive n‐type PbTiO 3 by a combustion method and p‐type Cu‐doped PbTiO 3 by an impregnation method to improve hydrogen production activity. Copper was doped into the PbTiO 3 lattice up to 1 wt %; any further increase in the loading resulted in the formation of CuO on the surface of the sample. Photoluminescence confirmed that 1 wt % Cu‐doped PbTiO 3 effectively suppressed the defects in PbTiO 3 , which helped to reduce the recombination rate of the photoinduced charge carriers. The prepared PbTiO 3 photocatalyst behaves as an n‐type semiconductor, whereas 1 wt % Cu‐doped PbTiO 3 behaves as a p‐type semiconductor. The photocatalytic hydrogen production activity of PbTiO 3 increased with increasing Cu content up to 1 wt % and thereafter decreased upon further loading. The 1 wt % Cu‐doped PbTiO 3 sample showed higher activity for hydrogen liberation than pristine PbTiO 3 (2.5 times) and all of the other CuO‐loaded samples . The energy conversion efficiency of 1 wt % Cu‐doped PbTiO 3 was 5.95 % for hydrogen production under visible‐light irradiation. The enhanced hydrogen production activity of Cu‐doped PbTiO 3 was discussed on the basis of optimum copper doping, photoluminescence intensity, and their band‐edge positions. However, the higher activity of CuO‐loaded (>1 wt %) PbTiO 3 relative to that of neat PbTiO 3 is perhaps a result of the extensive light absorption properties of the CuO nanoparticles, which help to generate more electron–hole pairs on the surface.