Ultrathin Metal-Organic Framework Nanosheets for Selective Photocatalytic C 2 H 2 Semihydrogenation in Aqueous Solution

The selective semihydrogenation of C H to C H in crude C H (with ~1 vol % C H contamination) is a crucial process in the manufacture of polyethylene. Comparing to conventional thermalcatalytic route with Pd as catalyst under high temperature with H as hydrogen source, photocatalytic C H reduction reaction with H O as hydrogen source can achieve high selectivity under milder conditions, but has rarely been reported. Here, we present a kind of ultrathin metal-organic framework nanosheets (Cu-Co-MNSs) that demonstrate excellent catalytic activities in the semihydrogenation of C H . Employing Ru(bpy) as the photosensitizer, this catalyst attains a noteworthy turnover number (TON) of 2124 for C H , coupled with an impressive selectivity of 99.5 % after 12 h visible light irradiation. This performance is comparable to molecular catalysts and notably surpasses the efficiency of bulk metal-organic framework materials. Furthermore, Cu-Co-MNSs achieve a 99.95 % conversion of C H under industrial relevant conditions (1.10 % C H in C H ) with 90.3 % selectivity for C H over C H , demonstrating a great potential for polymer-grade C H production.