Publications by authors named "Sungkwon Jeon"

Anion exchange membrane (AEM) water electrolysis (AEMWE) is considered an economical technology for producing green hydrogen energy. However, conventional AEMs comprising polymer backbones with anisotropically aligned cationic pendant groups exhibit unsatisfactory AEMWE performance and durability, limiting their practical implementation. Herein, a facile method for fabricating a durable high-performance AEM via a one-pot monomer-level Menshutkin (m-Men) reaction in a porous mechanical support is proposed.

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Anion-exchange membranes (AEMs) are the key components of AEM-based water electrolysis (AEMWE) for green hydrogen production. Unfortunately, many AEMs have unsatisfactory ion conductivity, and the factors governing their ion transport remain unclear. To address these limitations, herein, a new pyrrolidinium-containing diallylammonium-cyclopolymerized (PDT) AEM is proposed.

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High-performance and durable anion exchange membranes (AEMs) are critical for realizing economical green hydrogen production through alkaline water electrolysis (AWE) or AEM water electrosysis (AEMWE). However, existing AEMs require sophisticated fabrication protocols and exhibit unsatisfactory electrochemical performance and long-term durability. Here we report an AEM fabricated via a one-pot, in situ interfacial Menshutkin reaction, which assembles a highly cross-linked polymer containing high-density quaternary ammoniums and nanovoids inside a reinforcing porous support.

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There is a growing demand for adsorption technologies for recovering and recycling precious metals (PMs) in various industries. Unfortunately, amine-functionalized polymers widely used as metal adsorbents are ineffective at recovering PMs owing to their unsatisfactory PM adsorption performance. Herein, a star-shaped, hydrazide-functionalized polymer (S-PAcH) is proposed as a readily recoverable standalone adsorbent with high PM adsorption performance.

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Alkaline water electrolysis (AWE) is considered a promising technology for green hydrogen (H ) production. Conventional diaphragm-type porous membranes have a high risk of explosion owing to their high gas crossover, while nonporous anion exchange membranes lack mechanical and thermochemical stability, limiting their practical application. Herein, a thin film composite (TFC) membrane is proposed as a new category of AWE membranes.

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In this study, we prepared poly(acryloyl hydrazide) (PAH)-grafted cellulose nanocrystal (CNC-PAH) particles via the atom transfer radical polymerization method for application to Cr(VI) adsorption. The closely-packed PAH chains grafted on the cellulose nanocrystal (CNC) surface provide a high density of amine groups that can adsorb Cr(VI) through strong electrostatic, hydrogen bonding and chelating interactions. CNC-PAH exhibited the optimum Cr(VI) adsorption capacity at the solution pH = 3, where its electrostatic attraction with Cr(VI) was maximized.

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