Solar thermochemical conversion of CO2 via erbium oxide based redox cycle

Investigation of the viability of the erbium oxide‐based solar thermochemical CO2 splitting cycle is reported. This study aimed to explore the effect of partial thermal reduction (TR) of Er2O3 on the thermodynamic process parameters desirable to design a solar reactor system for the erbium oxide‐based CO2 splitting (ErO‐CS) cycle. First, the percentage TR of Er2O3 is estimated as a function of the TR temperature (). Acquired results indicated that to achieve a percentage TR of Er2O3 in the range of 5–100%; the solar reactor has to be functioned in the temperature range of = 2327–2677 K. The solar energy required to drive the ErO‐CS cycle () was observed to be on the higher side due to the obligation of the elevated values of . This rise in the as a function of percentage TR of Er2O3 reflected in a decrease in the solar‐to‐fuel energy conversion efficiency (). The maximum = 4.04% is achieved for a percentage TR of Er2O3 = 25% ( = 2432 K). By employing 100% heat recuperation, the (for percentage TR of Er2O3 = 25%) increased up to 5.79%.