Rational construction of noble metal-free Cu(I) anchored Zr-MOF for efficient fixation of CO2 from dilute gas at ambient conditions

Abstract

The utilization of carbon dioxide (CO2) from dilute gas as C1 feedstock for synthesis of high-value chemicals such as α-alkylidene cyclic carbonates is one of the promising approaches towards mitigating the increasing atmospheric CO2 concentration. Consequently, herein, we demonstrate the application of UiO-MOF functionalized with bipyridine sites for facile anchoring of catalytically active noble metal-free copper (I) sites by post-synthetic treatment. The Cu(I) anchored UiO-MOF exhibits an excellent catalytic activity for coupling CO2 with propargylic alcohols affording α-alkylidene cyclic carbonates, valuable commodity chemicals at mild conditions of 1 atm of CO2 (balloon). Furthermore, the MOF catalyst showed good activity for fixation carbon dioxide from dilute gas (CO2:N2 = 13:87%) condition. The superior catalytic performance of Cu(I)@UiO-MOF over the homogeneous counterpart has been attributed to a synergistic effect of high CO2-philicity of MOF and catalytic activity of copper (I) sites exposed in the 1D channels of the MOF. The catalyst can be recycled up to five cycles with retention of catalytic efficiency and its heterogeneity enjoyed over the reaction period. This work demonstrates the rational integration of non-noble metal catalytic sites in functionalized frameworks for the efficient fixation of CO2 from dilute gas into fine chemicals.