From plastic trash to solar hydrogen a practical method emerges

From plastic trash to solar hydrogen a practical method emerges
by Riko Seibo
Tokyo, Japan (SPX) Jun 12, 2025

A research team in South Korea has unveiled a solar-powered technique that transforms discarded plastic into clean hydrogen, offering a promising path to sustainable fuel generation.

Developed at the Institute for Basic Science (IBS) Center for Nanoparticle Research, the breakthrough system was spearheaded by Professors KIM Dae-Hyeong and HYEON Taeghwan of Seoul National University. Their innovation features a photocatalyst encased in a floating hydrogel polymer, enabling continuous hydrogen production from PET plastics using only sunlight and water.

Hydrogen is widely viewed as a vital clean energy carrier, but most current production relies on energy-intensive methods like methane steam reforming, which emit greenhouse gases. Photocatalysis offers a greener alternative, yet often struggles with stability and efficiency when exposed to harsh light and chemical environments.

To counter these limitations, the IBS team embedded the photocatalyst in a robust polymer network and positioned the active site at the water-air boundary. This configuration minimizes catalyst degradation, enhances gas separation, and prevents reverse reactions. As PET plastics decompose, they yield valuable compounds such as ethylene glycol and terephthalic acid, along with hydrogen gas.

"The key was engineering a structure that works not only in theory but also under practical outdoor conditions," said Dr. LEE Wanghee, postdoctoral researcher at MIT and co-first author of the study. "Every detail - from material design to the water-air interface - had to be optimized for real-life usability."

The system maintained its activity for more than two months under highly alkaline conditions and showed consistent performance across diverse water types, including seawater and tap water.

Field tests using a one-square-meter outdoor setup confirmed successful hydrogen production from PET-infused water under natural sunlight. Economic modeling further indicated that scaling up to 10 or even 100 square meters is feasible, potentially delivering affordable, zero-emission hydrogen fuel.

"This research opens a new path where plastic waste becomes a valuable energy source," stated Professor KIM Dae-Hyeong. "It's a meaningful step that tackles both environmental pollution and clean energy demand."

Professor HYEON Taeghwan noted, "This work is a rare example of a photocatalytic system that functions reliably in the real world - not just the lab. It could become a key stepping stone toward a hydrogen-powered, carbon-neutral society."

Research Report:Polymeric stabilization at the gas-liquid interface for durable solar hydrogen production from plastic waste