List of HEPs, OEPs and redox mediators used for visible-light-driven Z-scheme overall water splitting35,42–64.
| HEP | OEP | Mediator | pH | Light source, wavelength (λ nm) | H2 (μmol h−1) | O2 (μmol h−1) | AQY% (λ nm), STH (%) | Year (ref) |
|---|---|---|---|---|---|---|---|---|
| Pt/STO:Cr,Ta | PtOx/WO3 | IO3−/I− | 7.0 | 300 W Xe (>420) | 1.8 | 0.9 | 0.1 (420 nm) | 2001 (ref. 42) |
| Ru/STO:Rh | WO3 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 18.9 | 8.9 | n.r. | 2008 (ref. 43) |
| Ru/STO:Rh | BiVO4 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 19.2 | 9.7 | 0.3 (420 nm), 0.02 STH | 2008 (ref. 43) |
| Ru/STO:Rh | BiVO4 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 122.0 | 61.0 | 4.2 (420 nm), 0.1 STH | 2013 (ref. 44) |
| Pt/STO:Rh | WO3 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 7.8 | 4.0 | 0.5 (420 nm) | 2004 (ref. 45) |
| Pt/STO:Rh | Bi2MoO6 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 19.0 | 8.9 | 0.2 (440 nm) | 2004 (ref. 45) |
| Pt/STO:Rh | BiVO4 | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 15.0 | 7.1 | 0.4 (420 nm) | 2004 (ref. 45) |
| Ru/STO:Rh | IrOx/SrTiO3:Rh/Sb | Fe3+/Fe2+ | 2.4 | 300 W Xe (>420) | 3.0 | 1.4 | n.r. | 2014 (ref. 46) |
| Ru/STO:Rh | Bi4NbO8Cl | Fe3+/Fe2+ | 2.5 | 300 W Xe (>400) | 15.0 | 7.0 | 0.9 (420 nm) | 2018 (ref. 49) |
| Ru/STO:Rh | RuO2/Bi4NbO8Cl | Fe3+/Fe2+ | 2.4 | 300 W Xe (>400) | 11.3 | 5.8 | 0.7 (420 nm) | 2019 (ref. 48) |
| Ru/STO:Rh | RuO2/Bi4NbO8Cl | Fe3+/Fe2+ | 2.4 | 300 W Xe (>400) | 28.0 | 15.3 | 1.3 (420 nm) | 2019 (ref. 48) |
| Ru/STO:Rh | BiVO4 | [Co(bpy)3]3+/2+ | 3.8 | 300 W Xe (>420) | 100.0 | 47.0 | 2.1 (420 nm), 0.06 STH | 2013 (ref. 46) |
| Ru/STO:Rh | BiVO4 | [Co(phen)3]3+/2+ | 7.0 | 300 W Xe (>420) | 10.0 | 4.8 | n.r. | 2013 (ref. 46) |
| Ru/STO:Rh | TiO2:Cr,Sb | [Co(phen)3]3+/2+ | 7.0 | 300 W Xe (>420) | 1.3 | 0.7 | n.r. | 2013 (ref. 46) |
| Pt/TaON | PtOx/WO3 | IO3−/I− | 7.0 | 300 W Xe (>420) | 24.0 | 12.0 | 0.4 (420 nm) | 2005 (ref. 50) |
| Pt/ZrO2/TaON | PtOx/WO3 | IO3−/I− | 5.4 | 300 W Xe (420–800) | 33.0 | 16.0 | 6.3 (420 nm) | 2010 (ref. 51) |
| Pt/ZrO2/TaON | RuO2/TaON | IO3−/I− | 6.0 | 300 W Xe (>420) | 7.0 | 3.0 | 0.1 (420 nm) | 2011 (ref. 52) |
| Pt/ZrO 2 /TaON | Au/CoO x /BiVO 4 | [Fe(CN) 6 ] 3− /[Fe(CN) 6 ] 4− | 6.0 | 300 W Xe (>420) | 87.5 | 41.6 | 10.3 (420 nm), 0.5 STH | 2018 (ref. 35) |
| Pt/BaTaO2N | PtOx/WO3 | IO3−/I− | Without control | 300 W Xe (>420) | 6.6 | 3.0 | 0.1 (420–440 nm) | 2009 (ref. 53) |
| Pt/BaZrO3–BaTaO2N | PtOx/WO3 | IO3−/I− | 300 W Xe (350–800) | 22.4 | 9.3 | 0.0067 STH | 2013 (ref. 54) | |
| Pt/BaZrO3–BaTaO2N | TiO2 | IO3−/I− | 300 W Xe (350–800) | 21.3 | 9.4 | 0.014 STH | 2013 (ref. 54) | |
| MgTa2O6−xNy/TaON | PtOx/WO3 | IO3−/I− | 300 W Xe (>420) | 108.3 | 55.3 | 6.8 (420 nm) | 2015 (ref. 55) | |
| Pt/Sm2Ti2O2S5 | TiO2 (rutile) | IO3−/I− | 11.0 | 450 W Hg (>300) | 9.0 | 3.2 | n.r. | 2014 (ref. 56) |
| Ru/(CuGa)0.8Zn0.4S2 | BiVO4 | [Co(terpy)3]3+/2+ | Without control | 300 W Xe (>420) | 3.1 | 1.6 | 0.025 STH | 2015 (ref. 57) |
| Pt/NiS/La5Ti2AgS5O7 | PtOx/WO3 | I3−/I− | 4.0 | 300 W Xe (>420) | 11.1 | 5.4 | 0.12 (420 nm) | 2019 (ref. 58) |
| Ru/STO:Rh | BiVO4 | RGO | 3.5 | 300 W Xe (>420) | 11.0 | 5.5 | 1.03 (420 nm) | 2011 (ref. 59) |
| CrOx/Ru/STO:Rh,La | BiVO4:Mo | Au | 300 W Xe (>420) | 100.0 | 50.0 | 33 (419 nm), 1.1 STH | 2016 (ref. 60) | |
| Cr2O3/Ru/STO:Rh,La | BiVO4:Mo | Carbon | 6.8 | 300 W Xe (>420) | 90.0 | 45.0 | 26 (419 nm), 1.2 STH | 2017 (ref. 61) |
| RhCrOx/ZrO2/LaMg1/3Ta2/3O2N | BiVO4:Mo | Au | 300 W Xe (>420) | 1.1 | 0.6 | 0.07 (418 nm), 0.001 STH | 2016 (ref. 62) | |
| Cr2O3/Rh/La5Ti2Cu0.9Ag0.1S5O7:Ga | BiVO4 | Au | 6.9 | 300 W Xe (>420) | 20.0 | 10.0 | 4.9 (420 nm), 0.11 STH | 2018 (ref. 63) |
| La5Ti2Cu0.9Ag0.1S5O7:Ga | CoOx/LaTiO2N | Au | 11.0 | 300 W Xe (>420) | 0.5 | 0.2 | 0.04 (420 nm) | 2018 (ref. 64) |