Figure 18.

a) EDS elemental mapping images of C/N co‐doped Zn _x :Co _y @Cu photocathode catalyst. b) Photoelectrodes, photoelectrochemical cells, and paraffin products floated onto the surface of the electrolyte after the reaction. c) Proposed reaction mechanism of photoelectrocatalytic CO₂‐to‐paraffin conversion by using C/N co‐doped Zn _x :Co _y @Cu photocathode. Reproduced with permission.^{[ 140 ]} Copyright 2019, The Author(s). d) Band positions of N‐TiO₂/Ti₃C₂ photocathode and the redox potentials of CO₂ reduction at pH 7. Reproduced with permission.^{[ 142 ]} Copyright 2018, Elsevier Ltd. e) The proposed carriers transfer mechanism of polypyrrole/TiO₂ heterostructural catalyst during photoelectrochemical CO₂ reduction. Reproduced with permission.^{[ 143 ]} Copyright 2020, Elsevier B.V.