fig4
![Photothermal catalytic H<sub>2</sub> production over hierarchical porous CaTiO<sub>3</sub> with plasmonic gold nanoparticles](https://image.oaes.cc/ee9dbfb8-c16c-490f-a4b7-be23b47d91cd/5349.fig.4.jpg)
Figure 4. (A and B) SEM images of 3DOM CaTiO3-Au after photocatalytic reaction; (C) XPS Au 4f spectra of 3DOM CaTiO3-Au before and after photocatalytic reaction; (D) electrostatic potential difference brought by oxidization of gold atoms (the left and the middle are cross-section view of yz and xz plane, respectively. The right is a 3-D view of the electrostatic potential difference. The positive values indicate an elevated electrostatic potential by the addition of oxygen atoms); (E) H2 production from different substrates; and (F) the proposed mechanism.