Photochemical transformation of UiO-66-NH2 during hydrogen generation under solar irradiation

• Published in: Catalysis communications 2024-02, Vol.187, p.106858, Article 106858
• Main Authors: Gudiño, Lorena, Peñas-Garzón, Manuel, Rodriguez, Juan J., Bedia, Jorge, Belver, Carolina
• Format: Article
• Language: English
• Subjects: Hydrogen production; Photostability; Sodium sulfide/sodium sulfite scavenger; Solar photocatalysis; UiO-66-NH2
• ISSN: 1566-7367; 1873-3905
• DOI: 10.1016/j.catcom.2024.106858

This work reports for the first time the photochemical transformation suffered by the UiO-66-NH2 MOF during hydrogen production under solar irradiation using different scavengers. Triethanolamine caused the complete dissolution of the MOF, while Na2S/Na2SO3 transformed the UiO-66-NH2 into a novel Zr-based material characterized by an amorphous structure with a production rate of 0.439 μmol H2·gcat−1·h−1. The MOF-derived material maintained its performance during long-term on-stream experiments thanks to the electron transfer from the sulfide/sulfite ions to the valence band of the photocatalyst. However, significant doubts about the stability of UiO-66NH2 and other MOFs in the photocatalytic generation of hydrogen are arisen. [Display omitted] •UiO-66-NH2 suffered photochemical transformation during hydrogen generation.•UiO-66-NH2 derived in a novel MOF-material by reaction with Na2SO3/Na2S redox pair.•The novel MOF-derived material describes an amorphous structure.•Long-term hydrogen production was achieved with the derived material.•Sulfur ions and the photocatalyst valence band control the photocatalytic mechanism.