Metal-decorated porous organic frameworks with cross-linked pyridyl and triazinyl as efficient platforms for CO2 activation and conversion under mild conditions

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2022-10, Vol.445, p.136687, Article 136687
• Main Authors: Liu, Fangwang, Duan, Xinran, Dai, Xun, Du, Shanshan, Ma, Jingjing, Liu, Fusheng, Liu, Mengshuai
• Format: Article
• Language: English
• Subjects: CO2 conversion; Cyclic carbonate; Cycloaddition reaction; Multifunctional catalyst; Porous organic framework
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2022.136687

Heterogeneous Co@PTPOFs with multiple Lewis acid/basic sites are developed and show excellent activity for cycloaddition of CO2 and epoxides. [Display omitted] •Novel M@PPOFs with multiple Lewis acid/basic active sites are prepared facilely.•The M@PPOFs exhibit high specific surface area and good structural stability.•The 1.0Co@PPOFs-mediated CO2 coupling reaction can conduct under mild conditions.•The optimum catalyst shows excellent reusability and broad substrate scope.•An insight into the M@PPOFs-catalyzed cycloaddition mechanism is proposed. A series of metal-decorated porous organic frameworks (M@PTPOFs) with cross-linked pyridyl and triazinyl were fabricated through a two-step method. The structures of the PTPOFs and M@PTPOFs were systematically characterized. As heterogeneous catalysts with Lewis acid/basic sites, the M@PTPOFs were applied to catalyze the model cycloaddition of CO2 and epoxides. The optimal catalytic system and reaction parameters were investigated in detail. It was found that 1.0Co@PTPOF-400-15 cooperating with tetrabutylammonium iodide (TBAI) achieved the best catalytic performance, with a 96% product yield and 99% selectivity under mild conditions of 60 °C and 2.0 MPa CO2 for 5.0 h. Moreover, 1.0Co@PTPOF-400-15 could be easily recycled by centrifugation and reused multiple times with nearly unchanged catalytic activity. Finally, the product yield and reaction parameters were compared with those of reported heterogeneous catalysts, and the possible synergistic catalytic mechanism of 1.0Co@PTPOF-400–15/TBAI was proposed. The multiple Lewis acid/basic active sites, robust structure and excellent catalytic performance are useful for the development of other high-efficiency heterogeneous catalysts.