Table 1.
Comparison of the performance of sunlight-driven CO2 reduction devices
| Device configuration | Efficiency | Duration | Ref. | |||||
|---|---|---|---|---|---|---|---|---|
| OER | CO2RR | Photovoltaic | Electrolyte | BPM | STFCO2 | STF | ||
| SGC | a-Ag | GaInP/GaInAs/Ge | 0.4 M NaH2PO4 + 0.6 M Na2SO4 + NaOH | No | 13.9% | 15.6% | 19 h | This work |
| IrO2 | Au | perovskite PV | 0.5 M NaHCO3 | No | 6.5% | 7% | 18 h | 4 |
| IrO2 | CuAg | silicon PV | 0.5 M CsHCO3 | No | 2% | 3.2% | 6 h | 5 |
| IrO2 | CuAg | III–V/silicon tandem cells | 0.5 M CsHCO3 | No | 5.6% | 8.4% | − | 5 |
| IrO2 | polymetric Ru complex | SiGe triple-junction | 0.1 M phosphate buffer solution | No | 4.6% | − | 6 h | 6 |
| Co3O4 | NiN-GS | GaInP2/GaAs/Ge | 0.5 M KHCO3 | No | ∼10% | 10 h* | 7 | |
| SnO2–CuO | SnO2-CuO | GaInP/GaInAs/Ge | 0.1 M CsHCO3| 0.25 M CsOH | Yes | 12.4% | 13.8% | 5 h | 8 |
| Ni** | Zn | silicon PV** | 0.5 M KHCO3| 1 M KOH | Yes | 0.7% | 4.6% | 3 h | 9 |
| Ni** | Pd/C coated Ti | GaAs/InGaP/TiO2** | 2.8 M KHCO3| 1 M KOH | Yes | 10% | − | 3 h | 10 |
| IrO2 | Ag | ideal triple junction*** | − | − | 6.95% | − | 11 | |
*: refresh the electrolyte every few hours; **: integrated photoanode; ***: maximum achievable efficiency for CO generation from theoretical estimation using IrO2 for OER and silver for CO2RR