Journal Article

Visible-light-driven overall hydrogen peroxide (H2O2) photosynthesis is a promising strategy for sustainable production of H2O2. However, it is still limited to the design of robust photocatalysts with controlled charge transfer both in photogenerated carrier relaxation and charge separation processes to achieve efficient dualchannel H2O2 photogeneration. Herein, a novel photocatalyst of aminated mercurated graphyne (NH2-Hg-GY) is designed which achieves an overall visible light-driven co-catalyst-free photogeneration of H2O2 with a yield of 2112.6 mu mol h- 1 g- 1 in a saturated O2 atmosphere. Experimental and theoretical analysis revealed that NH2-HgGY can effectively promote the absorbance of photons and generate long-lived photoinduced charges, which are eventually transferred to the surface defect states through a dual-channel carrier migration process and achieve a dual-channel pathway for H2O2 photogeneration integrating the two-electron oxygen reduction reaction on the benzene ring and the two-hole water oxidation reaction on the alkynyl group in NH2-Hg-GY. Particularly, the synergy of the spx-p pi conjugation between the amino group and benzene and the d pi-p pi conjugation between Hg (II) ion and ethynyl unit within NH2-Hg-GY alters the electronic structures of mercurated graphyne, which realize controllable carrier migration and efficient charge separation, thus achieving a superior overall H2O2 photogeneration.