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

Abstract

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.