Figure 3

PEC-TE hybrid devices (a) Energy band diagram of PEC-TE hybrid device for Seebeck-voltage-driven PEC water-splitting reaction. (b) LSV curves of the HfOx/SiOx bilayer protected Si photocathode under application of Seebeck voltage as a function of temperature difference (ΔT). (c) Plots indicating ΔT-dependent reduced potential for PEC water-splitting reaction; Si photocathodes protected by various insulator layers. (d) Photocurrent and Pmax for PEC-TE device using planar Si and nanostructured Si (nano-Si) at ΔT of 62 K and 70 K. The grey line indicates the Pmax for the photovoltaic-electrolysis (PV-EC) device8.