Cofacial porphyrin organic cages. Metals regulating excitation electron transfer and CO₂ reduction electrocatalytic properties

Abstract

A comprehensive study of the photophysical behaviors and CO2 reduction electrocatalytic properties of a series of cofacial porphyrin organic cages reveals metals regulate the excitation electron transfer and CO2 reduction electrocatalytic properties.

Encapsulated Dye in Coordination-Assembled Octahedron for Visible-Light-Driven Proton Reduction and Nitroaromatic Hydrogenation

“…Each cobalt ion is coordinated by two NON chelators from two different ligands. The determined C–O, C–N, and N–N bond distances (Table S2) in the carbohydrazide groups of each ligand are all within the typical range observed for single and double bond lengths. , Under these conditions, the formation presents a typical pathway for proton migration in the balance between the ketoxime and amide tautomer of the ligand structure. The proton could readily move to an appropriate location during a reduction process. , Consequently, the structure was favorable for catalyzing the reduction of protons. − The spacing between the two adjacent cobalt ions and the two opposite cobalt ions in the octahedron are 14.27 and 20.18 Å, respectively.…”

“…The determined C−O, C−N, and N−N bond distances (Table S2) in the carbohydrazide groups of each ligand are all within the typical range observed for single and double bond lengths. 24,25 Under these conditions, the formation presents a typical pathway for proton migration in the balance between the ketoxime and amide tautomer of the ligand structure. The proton could readily move to an appropriate location during a reduction process.…”

Robust Nitro-Functionalized {Zn3}-Organic Framework for Excellent Catalytic Performance on Cycloaddition Reaction of CO2 with Epoxides and Knoevenagel Condensation

“…Considering the exposed open metal sites, rich −NO 2 groups, substantial CO 2 adsorption value, high inherent physicochemical stability, and abnormally large nanopore, the catalytic performance of NUC-80a for the heterogeneous cycloaddition of CO 2 with epoxides to prepare relevant cyclic carbonates was studied by using propylene oxide (PO) as model epoxide to react with 1 atm CO 2 gas flow. As given in entry 1 of Table , although the resulted yield of 26% was not very high, it could fully demonstrate that NUC-80a had catalytic activity on the cycloaddition of CO 2 with PO and had higher catalytic activity than our previous nitrogen-free frameworks. , In contrast, the yield of such reaction was 5% in the presence of 1.5 mol % n -Bu 4 NBr, which was often chosen as a cocatalyst due to its nucleophilic Br – ion. − Consequently, the combination of 0.01 mol % and 1.5 mol % n -Bu 4 NBr was introduced to the cycloaddition reaction, which resulted in a 39% yield of propylene carbonate (PC), consistent with the reported yield growth trend due to the completed catalytic roles of MOF-based catalysts and n -Bu 4 NBr. , Next, a series of experiments were carried out to optimize the catalytic reaction conditions, such as catalyst dosage, temperature, and time. As given in entries 3–7, the yield showed a rapid and then slow increase along with the increase of NUC-80a loading (0.01–0.09 mol %), which reached 0.09 mol %, and the yield rose to 99.0% (entry 7).…”

Ionic porous porphyrin cage as a superior catalyst for photocatalytic oxidization

“…However, as for the four Q-bands ranging from 500 to 700 nm in TPP, they transformed into a broad adsorption band and experienced an obvious bathochromic shift in TPPCage•8PF 6 and TPPCage•8I, probably due to the formation of the cage structure that hinders the porphyrin accumulation and facilitates the charge transfer processes. 38,42 Notably, compared to TPPCage•8PF 6 , TPPCage•8I displayed a slightly red-shifted maximum absorption band, highlighting the role of altered charge transfer in improving the light-absorption ability. It should be noted that all three materials displayed similar UV-vis absorption spectra measured in DMF (Fig.…”