An amine-functionalized, crosslinked porous polymer is synthesized by linking 1,4-benzenediamine and pyrrole with p-formaldehyde in the presence of hydrochloric acid catalyst. The resulting polymer was structurally characterized and proven permanently porous with a surface area of 305 m² g⁻¹. The high concentration of amines (–NH– and –NH₂) within the backbone of the polymer result in exceptional selectivity (141) for CO₂ over N₂ and dynamic capacity (15.1 cm³ g⁻¹) in the presence of water (20 : 80 v/v CO₂ : N₂, 91% relative humidity, 1 bar, and 298 K). The performance of this polymer is maintained over 45 cycles without loss of selectivity, capacity, nor recyclability at room temperature; making it stand out among all porous organic materials used for carbon capture.

Solid-state polymer electrolytes (SPEs) possess several favorable properties, such as high flexibility, easy processability, and better safety for batteries. Thus, SPEs are attracting considerable attention for the development of safer Li ion batteries. However, SPEs typically lack the required ionic conductivity for improved Li⁺ transportation. Therefore, suitable fillers are often used to prepare composite polymer electrolytes (CPEs) with improved ionic conductivity. In this direction, a novel CPE with increased electrochemical stability and durability was prepared by incorporating highly porous Zr-based metal–organic frameworks (MOFs), herein referred to as ZR8, as fillers in poly(ethylene oxide) (PEO)/Li salt systems. PEO in the prepared CPE showed low crystallization ratios, and the CPE showed enhanced Li⁺ ion transportation, thereby improving mechanical and fire-retardant properties. It was also able to hinder Li dendrite formation and eventually facilitated efficient transport of Li⁺ ions through the electrolyte. A high specific surface area, the presence of Lewis acid–base sites, and good thermal and chemical stability of the ZR8 filler contributed to the improved electrolyte performance. CPE prepared with 7.5% ZR8 fillers showed a good ionic conductivity of 2.53 × 10⁻⁴ S cm⁻¹ at 30 °C and 1.35 × 10⁻³ S cm⁻¹ at 60 °C and an electrochemical window of ∼5.58 V. The [Li|ZR8-7.5|Li] cell showed an excellent stability in 8000-h operation without any flaw (at 60 °C and a current density of 100 μA cm⁻²). Additionally, the [Li|ZR8-7.5|LFP] cell was able to retain over 80% of its initial capacity (144.9 mA h g⁻¹ at 0.5C) even after 800 cycles.

The facile and environmentally friendly synthesis of porous organic polymers with designed polar functionalities decorating the interior frameworks as an excellent adsorbent for selective carbon dioxide capture and metal ion removal is a target worth pursuing for environmental applications. In this regard, two azo-linked porous organic polymers denoted man-Azo-P1 and man-Azo-P2 were synthesized in water by the azo-linking of 4,4'-diaminobiphenyl (benzidine) and 4,4'-methylenedianiline, respectively, with 1,3,5-trihydroxybenzene. The resulting polymers showed good BET surface areas of 290 and 78 m² g^-1 for man-Azo-P1 and man-Azo-P2, respectively. Due to the enriched core functionality of the azo (-N=N-) and hydroxyl groups along with the porous frameworks, man-Azo-P1 exhibited a good CO₂ uptake capacity of 32 cm³ g^-1 at 273 K and 1 bar, in addition to the remarkable removal of lead (Pd), chromium (Cr), arsenic (As), nickel (Ni), copper (Cu), and mercury (Hg) ions. This performance of the synthesized man-Azo-P1 and man-Azo-P2 in the dual application of CO₂ capture and heavy metal ion removal highlights the unique properties of azo-linked POPs as excellent and stable sorbent materials for the current challenging environmental applications.