7Uniqueness of properties and robustness of structure makes porphyrins nature's favorite catalysts. 8 They have grabbed human attention since decades due to its intense colours and in modern times the 9 interest in these molecules has sharply increased, owing to their use for handling some tough 10 problems, including medical and environmental issues. Nowadays much attention is being focused 11 on the development of materials for the capture and conversion of CO 2 into value added products and 12 porphyrins are not lagging behind in extending their favor. The idea that porphyrins are poor 13 absorption materials since are generally plnar compounds has been belied by the development of new 14 efficient porphyrin-based materials, and the development of reliable synthetic routes for porphyrin 15 based nanoreactors such as covalent-organic frameworks (COF) and metal-organic frameworks 16 (MOF) as porous materials has facilitated to overcome the underlying CO 2 reactivity challenges.17Porphyrin-based materials behaving as nanoreactors are very promising for CO 2 capture and 18 conversion due to the presence of basic pyrrole containing macrocyclic cavity and large aromatic 19 rings which facilitates strong interactions with CO 2 . This review is intended to provide an overview 20 of up-to-date progress made in the area of the CO 2 capture and conversion involving porphyrin-based 21 molecular materials and nanoreactors, bearing important structural features in terms of surface area, 22 porosity, CO 2 uptake and the possibility of its catalytic conversion to chemically valuable products.

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The aggregation process of meso-tetra(4-aminosulfonylphenyl)porphyrin (PC 0), of butyl and dodecyl derivatives (PC 4 and PC 12 , respectively) in the presence of aerosol-OT (AOT) reversed micelles with different values of ω 0) [water]/[AOT] was investigated using steady-state extinction, fluorescence, and resonance light scattering (RLS) techniques. The scattering has been accounted for and the absorption spectra corrected from the extinction spectra. In homogeneous solutions, the porphyrins exist as a monomer showing the Soret band around 420 nm and emission bands at 650 and 716 nm. In reverse micelles, the spectra vary according to the chain length and the amount of solubilized water. Only PC 12 is dissolved as a monomer at ω 0) 0, and PC 4 shows some degree of aggregation. PC 0 is present largely as an aggregate. At ω 0 * 0, a complete aggregation is observed for PC 4 and PC 12 , whereas in PC 0 , some degree of disaggregation was detected. The extinction spectra of PC 0 and PC 4 in aggregate forms show a broad and red shifted Soret band indicating J aggregates. By contrast, the Soret band intensity of PC 12 decreases and a new band around 376 nm appears with a broadening of the monomer Soret band which reflects H aggregates. RLS shows a strong signal for PC 12 at red spectral region at high ω 0 indicating J aggregate types. The fluorescence spectra showed the new band around 670 nm for PC 0 and PC 12 , whereas in PC 4 , only blue shifted bands were observed with ω 0 increase. The global fluorescence quantum yield of the PC 12 aggregates is lower than the respective monomer. The aggregate sizes were followed by RLS measurements which showed an increase of intensity at around 440 nm. The aggregation dynamics is dependent on both the porphyrin concentration and ω 0 .

Mutual diffusion coefficients (interdiffusion coefficients) and molar conductivities have been measured for copper(II) chloride in water at 298.15 K and 310.15 K at concentrations between 0.005 mol‚dm-3 and 0.05 mol‚dm-3. The diffusion coefficients were measured using a conductometric cell. The experimental data are discussed on the basis of the Onsager-Fuoss model. The Nernst diffusion coefficients derived from diffusion (1.297 × 10-9 and 1.690 × 10-9) m 2 ‚s-1 and from conductance (1.282 × 10-9 and 1.663 × 10-9) m 2 ‚s-1 at two temperatures (298.15 K and 310.15 K, respectively) are in good agreement.