Bifunctional catalyst of a metallophthalocyanine-carbon nitride hybrid for chemical fixation of CO₂to cyclic carbonate

Abstract

5Chemical fixation of carbon dioxide (CO2) to cyclic carbonates were investigated by using bifunctional nucleophile-electrophile catalysts of metallophthalocyanine-carbon nitride hybrid [MPc/g-C3N4 (M = Co, Cu)] in the absence of any co-catalysts and organic solvents. MPc/g-C3N4 was readily obtained by a direct calcination of mixture of dicyandiamide and metallophthalocyanine under flowing-nitrogen atmosphere, and the MPc/g-C3N4 prepared at 480 °C (MPc/g-C3N4-480) showed the highest catalytic performance 10 toward the cycloaddition reaction of CO2 to epichlorohydrin (ECH). For bifunctional MPc/g-C3N4, MPc species function as Lewis acidic center for ECH activation via electrophilic attack; while, g-C3N4 moiety, possessing abundant and uncondensed species with the forms of primary amine (NH2) groups and secondary amine (C-NH-C) groups at the edges of graphitic sheets as edge defects, acts as organic base for CO2 activation through nucleophilic attack. The developed MPc/g-C3N4 is stable and insoluble in any 15 commonly used organic solvents and behaves as heterogeneous catalyst, leading to a facile separation and recycling in CO2 fixation reaction. 75 Hybrid materials of metallophthalocyanine and carbon nitride are recyclable catalysts for CO2 fixation to cyclic carbonate.

Conversion of CO2 into Chloropropene Carbonate Catalyzed by Iron (II) Phthalocyanine Hypercrosslinked Porous Organic Polymer

“…The catalytic activity of FePc-POP was compared with those reported for some heterogeneous porphyrin- [ 19 , 20 , 21 , 22 , 23 , 38 , 39 , 40 , 41 ] or phthalocyanine-based [ 42 , 43 ] catalysts in the cycloaddition of CO 2 to ECH ( Table 3 ). The Mg porphyrin based catalysts (entries 1 and 2) work with very high substrate/metal ratios which result in very high TON values but higher CO 2 pressures and temperatures are needed to achieve total conversion.…”

First Photocatalytic Synthesis of Cyclic Carbonates from CO2 and Epoxides Using CoPc/TiO2 Hybrid under Mild Conditions

“…The peak at 796.9 eV corresponding to Co 2p 1/2 also confirmed the presence of cobalt metal in +2 oxidation state (Figure 7d). 44 Thermal stability of the synthesized materials was determined by thermogravimetric analysis (TGA) as shown in Figure 8. In CoPc (Figure 8a) an initial weight loss near to 200 °C was due to the evaporation of the adsorbed solvent or water molecules.…”

Engineering of relevant photodynamic processes through structural modifications of metallotetrapyrrolic photosensitizers

“…in Sn-porphyrin/TiO 2 -Pt system) or carbon dioxide fixation to cyclic carbonates (e.g. in Cu, Co-porphyrin/g-C 3 N 4 system) [255,256].…”