Construction of Frustrated Lewis Pairs in Poly(heptazine Imide) Nanosheets via Hydrogen Bonds for Boosting CO2 Photoreduction

The creation of frustrated Lewis pairs on catalyst surface is an effective strategy for tuning CO₂ activation. The critical step in the formation of frustrated Lewis pairs is the spatial effect of proximal Lewis acid-Lewis base pairs. Here, we demonstrate a facile surface functionalization methodology that enables hydrogen bonding between N and H atoms to mediate the construction of frustrated Lewis pairs in poly(heptazine imide), thereby increasing the propensity to activate CO₂ molecules. Experimental and theoretical results show that the construction of active hydrogen bonding regions can facilitate the bending of CO₂ molecules. Furthermore, the delocalization of electron clouds induced by the hydrogen bonding-mediated frustrated Lewis pairs can promote the heterolytic cleavage and photocatalytic conversion of CO₂. This work highlights the potential of utilizing hydrogen bonding-mediated strategy in heterogeneously photocatalytic activation of CO₂ over polymer materials.