1
A two-step solar thermochemical CO 2 -splitting cycle using Zn/ZnO redox reactions
1 - K
298
2 2 1
mol kJ
∆
H 350
O Zn ZnO
= +
⇒
o
Net reaction Solar step:
Non-solar step:
Maximum solar-to-
chemical efficiency of 39%
1 - K
298 2
mol kJ 68 - H
CO ZnO CO
Zn
=
∆
+ +
⇒o
2 2 1
2
CO O
CO
⇒
+
• Gálvez et al., Energy & Fuels 5 (2008) 3544–3550
• Loutzenhiser et al., Energy & Fuels 23 (2009) 2832-2839
2