Porosity Design on Conjugated Microporous Poly(Aniline)S for Exceptional Mercury(II) Removal

Abstract

The use of conjugated microporous polymers (CMPs) in practical wastewater treatment demands further design on the pore structure, otherwise their adsorption capacities toward heavy-metal ions were moderate. Here, we report a rational design approach, which produces hybrid molecular pores in conjugated microporous poly­(aniline)­s (CMPAs) for mercury removal. It is achieved through a delicate interval introduction of linkers with differential molecular lengths during polymerization, acquiring both diffusion channels and storage pores for radical enhancement of mass transfer and adsorption storage. The resulting CMPA-M featured a large adsorption capacity of 975 mg g–1 and rapid kinetics that could remove 94.8% of 50 mg g–1 of mercury­(II) within a very short contact time of 48 s, with a promising initial adsorption rate h as high as 113 mg g–1 min–1, which was 2.54-fold larger in the adsorption capacity and 45.2-fold faster in the adsorption efficiency compared with the undeveloped CMPAs. More importantly, our CMPA-M-2, with robust stability and easy reusability, was able to scavenge over 99.9% of mercury­(II) from the actual wastewater in a harsh condition with a very low pH of 0.77, extremely high salinity of 53,157 mg L–1, and complex impurities, featuring exceptional selectivity that allows us to extract and recycle a high purity of 99.1% of mercury from the wastewater. These outcomes demonstrate the unprecedented potential of CMPs for environmental remediation and real-world mercury extraction and present benchmarks for CMP-based mercury adsorbents.

Ultrastable Three-Dimensional Triptycene- and Tetraphenylethene-Conjugated Microporous Polymers for Energy Storage

“…Increasing energy consumption and climate damage from the use of conventional fossil fuels are spurring the development of alternative energy sources and efficient energy storage devices. In particular, supercapacitors have become attractive devices because of their rapid charge/discharge switching, high power density, and long cycle life. − The storage of electrical charge in supercapacitors arises from their functioning as electrochemical pseudocapacitors or electrical double-layer capacitors (EDLCs). − Charge storage in pseudocapacitors, also known as redox supercapacitors, operates through reversible redox reactions occurring between the electrolyte and electrode materials. − In EDLCs, charge storage is more of a physical process, involving adsorption/desorption of charged ions at the interface between the electrolyte and the electrode; accordingly, EDLCs require a high surface area, a narrow and consistent pore size distribution, and a large pore volume if they are to provide high capacitance. , Porous organic polymers (POPs) are interesting materials because of their potential for application in various fieldsespecially for energy storage and gas capture. − According to IUPAC classification, porous materials can be divided into macroporous (pore diameter: >50 nm), mesoporous (2–50 nm), or microporous (<2 nm). POPs can also be defined in terms of their synthetic materials and their methods of constructed routes, for example, as covalent organic frameworks (COFs), covalent triazine frameworks (CTFs), hyper-crosslinked polymers (HCPs), and conjugated microporous polymers (CMPs). − CMPs are particularly interesting because they are amorphous materials possessing linked π-conjugated building blocks, where the sizes of the linkers can range from small phenyl units to bicyclic and macrocyclic moieties.…”

Conjugated Microporous Poly(aniline) Enabled Hierarchical Porous Carbons for Hg(II) Adsorption

“…The thermogravimetric analysis (TGA) curve of the PTPA was conducted to understand the pyrolysis process of these rigid 3D networks. As shown in Figure (a), the weight was gradually lost as the temperature increased due to the stepping pyrolysis of the organic groups on the PTPA, and 71.7% of the mass was kept when heated upon 800 °C, revealing the high polymerization degree of this polymer that could be an appealing platform as the carbon precursor with a high retention of porosity and heteroatoms . After effective thermotreatment when heated to above 800 °C, all of peaks assigned to functional groups on the PTPA disappeared as observed in Fourier transform infrared spectroscopy (FTIR) (shown in Figure (b)), further confirming the successful synthesis of the carbon materials.…”

Contribution Evaluation of Physical Hole Structure, Hydrogen Bond, and Electrostatic Attraction on Dye Adsorption through Individual Experiments

“…This unique characteristic of the adsorbent brought the ease in the diffusion and migration for MB molecules. Moreover, the stretched polymer chains have a high efficiency for the combination reaction between -COONa groups and MB molecules [32][33][34].…”