Exploring the additive effect of zirconium oxide in cerium oxide carbonate hydrate for hydrogen production through heterogeneous photocatalysis

Abstract This manuscript emphasizes the use of innovative heterojunction materials containing cerium oxycarbonates and zirconium oxide for hydrogen production as a renewable energy source through photocatalytic processes. Samples of Ce(CO 3 ) 2 O∙H 2 O were modified with ZrO 2 at molar concentrations of 4.0%, 6.0%, 8.0%, and 10.0%. It was found that adding ZrO 2 caused the formation of a new phase, cerium hydroxycarbonate (CeCO 3 OH). This produced a ternary material composed of Ce(CO 3 ) 2 O∙H 2 O, CeCO 3 OH, and ZrO 2 . The interaction among these three phases enhances hydrogen production via photocatalysis. The sample with an 8.0% molar concentration of ZrO 2 , labeled as CEZR8, achieved the highest hydrogen yield at 4715 µmolg −1 . Meanwhile, the bare Ce(CO 3 ) 2 O∙H 2 O and ZrO 2 samples showed no photocatalytic activity. This research demonstrates a synergistic effect among the three phases that boosts charge-carrier transfer, reduces recombination of photogenerated holes and electrons, and thereby increases hydrogen generation. Graphic Abstract