Porous Organic Polymers Derived from Ferrocene and Tetrahedral Silicon-Centered Monomers for Carbon Dioxide Sorption

Herein, we present two novel ferrocene-containing porous organic polymers, FPOP-1 and FPOP-2, by the Heck reactions of 1,1'-divinylferrocene with two tetrahedral silicon-centered units, i.e., tetrakis(4-bromophenyl)silane and tetrakis(4'-bromo-[1,1'-biphenyl]-4-yl)silane. The resulting materials possess high thermal stability and moderate porosity with the Brunauer-Emmer-Teller (BET) surface areas of 499 m2 g-1 (FPOP-1) and 354 m2 g-1 (FPOP-2) and total pore volumes of 0.43 cm3 g-1 (FPOP-1) and 0.49 cm3 g-1 (FPOP-2). The porosity is comparable to previously reported ferrocene-containing porous polymers. These materials possess comparable CO2 capacities of 1.16 mmol g-1 (5.10 wt%) at 273 K and 1.0 bar, and 0.54 mmol g-1 (2.38 wt%) at 298 K and 1.0 bar (FPOP-1). The found capacities are comparable to, or higher than many porous polymers having similar or higher surface areas. They have high isosteric heats of up to 32.9 kJ mol-1, proving that the affinity between the polymer network and CO2 is high, which can be explained by the presence of ferrocene units in the porous networks. These results indicate that these materials can be promisingly utilized as candidates for the storage or capture of CO2. More ferrocene-containing porous polymers can be designed and synthesized by combining ferrocene units with various aromatic monomers under this strategy and their applications could be explored.

A spirobifluorene-based water-soluble imidazolium polymer for luminescence sensing

A water-soluble luminescent sensor based on a spirobifluorene-based imidazolium polymer is developed for the selective sensing of Fe³⁺ and Cr₂O₇²⁻.

Synthesis of Novel Heteroatom-Doped Porous-Organic Polymers as Environmentally Efficient Media for Carbon Dioxide Storage

The high carbon dioxide emission levels due to the increased consumption of fossil fuels has led to various environmental problems. Efficient strategies for the capture and storage of greenhouse gases, such as carbon dioxide are crucial in reducing their concentrations in the environment. Considering this, herein, three novel heteroatom-doped porous-organic polymers (POPs) containing phosphate units were synthesized in high yields from the coupling reactions of phosphate esters and 1,4-diaminobenzene (three mole equivalents) in boiling ethanol using a simple, efficient, and general procedure. The structures and physicochemical properties of the synthesized POPs were established using various techniques. Field emission scanning electron microscopy (FESEM) images showed that the surface morphologies of the synthesized POPs were similar to coral reefs. They had grooved networks, long range periodic macropores, amorphous surfaces, and a high surface area (SBET = 82.71–213.54 m2/g). Most importantly, they had considerable carbon dioxide storage capacity, particularly at high pressure. The carbon dioxide uptake at 323 K and 40 bar for one of the POPs was as high as 1.42 mmol/g (6.00 wt %). The high carbon dioxide uptake capacities of these materials were primarily governed by their geometries. The POP containing a meta-phosphate unit leads to the highest CO2 uptake since such geometry provides a highly distorted and extended surface area network compared to other POPs.

Adamantane-Based Micro- and Ultra-Microporous Frameworks for Efficient Small Gas and Toxic Organic Vapor Adsorption

Microporous organic polymers and related porous materials have been applied in a wide range of practical applications such as adsorption, catalysis, adsorption, and sensing fields. However, some limitations, like wide pore size distribution, may limit their further applications, especially for adsorption. Here, micro- and ultra-microporous frameworks (HBPBA-D and TBBPA-D) were designed and synthesized via Sonogashira–Hagihara coupling of six/eight-arm bromophenyl adamantane-based “knots” and alkynes-type “rod” monomers. The BET surface area and pore size distribution of these frameworks were in the region of 395–488 m² g⁻¹, 0.9–1.1 and 0.42 nm, respectively. The as-made prepared frameworks also showed good chemical ability and high thermal stability up to 350 °C, and at 800 °C only 30% mass loss was observed. Their adsorption capacities for small gas molecules such as CO₂ and CH₄ was 8.9–9.0 wt % and 1.43–1.63 wt % at 273 K/1 bar, and for the toxic organic vapors n-hexane and benzene, 104–172 mg g⁻¹ and 144–272 mg g⁻¹ at 298 K/0.8 bar, respectively. These are comparable to many porous polymers with higher BET specific surface areas or after functionalization. These properties make the resulting frameworks efficient absorbent alternatives for small gas or toxic vapor capture, especially in harsh environments.

New Eco-Friendly Phosphorus Organic Polymers as Gas Storage Media

Three phosphate esters 1⁻3 were successfully synthesized from the reaction of 2-, 3- and 4-hydroxybenzaldehyde with phosphoryl chloride. Reactions of 1⁻3 with benzidine in the presence of glacial acetic acid gave the corresponding novel phosphorus organic polymers 4⁻6 containing the azomethane linkage. The structures of the synthesized compounds were confirmed by Fourier transform infrared spectroscopy, nuclear magnetic resonance and elemental analysis. Interesting physiochemical properties for the polymeric materials 4⁻6 were observed using a combination of several techniques such as gel permeation chromatography, scanning electron microscopy, Brunauer⁻Emmett⁻Teller and nitrogen adsorption⁻desorption isotherm, Barrett⁻Joyner⁻Halenda and H-sorb 2600 analyzer. The mesoporous polymers 4⁻6 exhibit tunable porosity with Brunauer⁻Emmett⁻Teller surface area (SABET = 24.8⁻30 m²·g⁻1), pore volume (0.03⁻0.05 cm³·g⁻1) and narrow pore size distribution, in which the average pore size was 2.4⁻2.8 nm. Polymers 4⁻6 were found to have high gas storage capacity and physico-chemical stability, particularly at a high pressure. At 323 K and 50 bars, polymers 4⁻6 have remarkable carbon dioxide uptake (up to 82.1 cm³·g⁻1) and a low hydrogen uptake (up to 7.4 cm³·g⁻1). The adsorption capacity of gasses for polymer 5 was found to be higher than those for polymers 4 and 6.

Charged Metalloporphyrin Polymers for Cooperative Synthesis of Cyclic Carbonates from CO2 under Ambient Conditions

A facile and one-pot synthesis of metalloporphyrin-based ionic porous organic polymers (M-iPOPs) was performed through a typical Yamamoto-Ullmann coupling reaction for the first time. We used various characterization techniques to demonstrate that these strongly polar Al-based materials (Al-iPOP) possessed a relatively uniform microporosity, good swellable features, and a good CO₂ capture capacity. If we consider the particular physicochemical properties, heterogeneous Al-iPOP, which bears both a metal active center and halogen anion, acted as a bifunctional catalyst for the solvent- and additive-free synthesis of cyclic carbonates from various epoxides and CO₂ with an excellent activity and good recyclability under mild conditions. Interestingly, these CO₂ -philic materials could catalyze the cycloaddition reaction smoothly by using simulated flue gas (15 % CO₂ in N₂ , v/v) as a raw material, which indicates that a stable local microenvironment and polymer swellability might promote the transformation. Thus, the introduction of polar ionic liquid units into metalloporphyrin-based porous materials is regarded as a promising new strategy for the chemical conversion of CO₂ .

Synthesis of thermochemically stable tetraphenyladamantane-based microporous polymers as gas storage materials

In view of environmental pollution control and purification of natural gases, developing ideal porous materials for small gas molecule (hydrogen, methane and carbon dioxide) capture is an important, pressing challenge.

BODIPY-containing porous organic polymers for gas adsorption

BODIPY-containing microporous organic polymers were synthesized via a Sonogashira–Hagihara coupling reaction of a BODIPY derivative and a range of aryl–alkyne monomers.

Microporous organic polymers based on tetraethynyl building blocks with N-functionalized pore surfaces: synthesis, porosity and carbon dioxide sorption

We have synthesized nitrogen-rich polymers by copolymerization of tetraethynyl monomers with tris(4-iodophenyl)amine or 4,4′-diiodoazobenzene. Azobenzene-based polymers exhibited excellent CO₂ adsorption selectivity against N₂.