We design polymers from the monomer up — controlling electron affinity, steric profile, and ion-channel architecture — so that the membranes, ionomers, and binders for water electrolysis are no longer the bottleneck of the green hydrogen economy.
The Park Research Group operates at the intersection of synthetic polymer chemistry and electrochemical engineering. Hosted within the Hydrogen Energy Research Center at KRICT, our work spans the full development chain — from monomer synthesis and superacid-catalyzed polycondensation, through morphology characterization with synchrotron scattering, to membrane-electrode-assembly (MEA) fabrication and single-cell electrolyzer testing.
Our perspective is shaped by two complementary traditions. Fisrt, the discipline of regio-controlled conjugated polymer design — built through years of work on polythiophene block copolymers and imine-incorporated transient electronics — gives us the molecular vocabulary to dictate how a polymer chain sits, packs, and interacts with adjacent surfaces. On the other, three years of intensive work on AEMWE, PEMWE, and AWE systems at KIER has taught us what the field actually needs: ionomers that don't poison the catalyst, membranes that don't swell into pieces, and large-area separators that survive thousands of duty cycles. The Park Group is built to deliver both — molecular insight and device-level realism.
Each theme begins with an open challenge that the polymer-electrolysis community must solve for green hydrogen to become economically viable — and explains how our group attacks it. Themes 1–5 are anchored in water electrolysis; theme 6 keeps the door open to our foundational work in conjugated and functional polymers, which remains a fertile source of molecular design ideas
i.
Tackling the catalyst-poisoning paradox
The Challenge
Planar aromatic ionomer backbones undergo strong π–π stacking with Pt/C surfaces, blocking active sites and lowering the effective triple-phase boundary. Pure alkyl-substituted ionomers solve this but lose conductivity and swell uncontrollably. The community urgently needs a third path that breaks the adhesion-vs-conductivity trade-off.
AEMWE Ionomer
ii.
Designing for 1000+ hours at 60–80 °C in concentrated KOH
The Challenge
Quaternary ammonium cations on flexible polyether backbones degrade rapidly under alkaline conditions, while rigid aromatic backbones with cyclic ammoniums (piperidinium, pyrrolidinium) compromise on processability. Long-term stability data beyond 1000 h is still rare in the literature.
AEMWE · Durability
iii.
Controlling channels at the 5–20 nm scale
The Challenge
Ion conductivity scales with continuous hydrophilic channels — but these same channels drive water uptake, dimensional swelling, and gas crossover. Engineering well-ordered microphase separation, akin to what Nafion does naturally, in hydrocarbon AEMs remains a fundamental design problem.
Block Copolymer · Morphology
iv.
Beyond PFAS — toward fluorine-reduced, mechanically robust PEMs
The Challenge
Pending PFAS regulations and the high cost of Nafion-class perfluorosulfonic-acid membranes are forcing the PEMWE community to develop hydrocarbon and partially-fluorinated alternatives — but these typically lack the mechanical strength and chemical durability of PFSA. Reinforcement scaffolds and radical scavengers must be integrated without sacrificing proton conductivity.
PEMWE · Composite · Radical Scavenger
v.
Scaling Zirfon-type separators to 600 cm² and beyond
The Challenge
Industrial AWE remains the lowest-cost route to green hydrogen, but Zirfon-class polysulfone/zirconia diaphragms suffer from poor wetting, uneven gas evolution, and limited resistance to thermal-mechanical cycling at commercial scales. Bridging the gap between lab coupons (few cm²) and industrial cells (≥600 cm²) is a mostly unsolved engineering problem.
AWE · Zirfon · Scale-up · Industry partnership
vi.
Our molecular toolbox — and a window for new directions
The Foundation
Many of the design principles we apply to ion-conducting polymers were forged in the conjugated polymer community — regio-regularity control, block copolymer architecture, side-chain engineering, and transient/degradable design.
Organic Transistor · Transient Electronics · Thin Film Sensor