Covalent Triazine Frameworks Embedded with Ir Complexes for Enhanced Photocatalytic Hydrogen Evolution

Covalent triazine frameworks (CTFs) with two-dimensional conjugated structures and a high nitrogen content have potential for photocatalytic hydrogen evolution (PHE). Herein, we show a strategy to boost the photocatalytic performance of a CTF containing bipyridine (bpy) units (PhBp-CTF). Through a postcomplexation reaction of the PhBp-CTF with Ir-2(ppy)(4)(mu-Cl)(2), the Ir complexes of [Ir(bpy)(ppy)(2)](3+) are successfully embedded inside to form PhBp-CTF-Ir. The accurate content and valence state of Ir have been confirmed by advanced spectroscopies. PhBp-CTF-Ir shows a PHE rate of 4805 mu mol g(-1) h(-1), while its precursor without Ir complexes has a rate of 3175 mu mol g(-1) h(-1). The enhanced photocatalytic performance is attributed to the Ir complexes inside PhBp-CTF-Ir, which act as not only an effective photosensitizer but also a proton reduction catalyst.