Solving two problems at once: researchers at the University of Adelaide have developed a reactor that converts plastic waste into hydrogen using sunlight. According to the team, which published its findings in May 2026, the system runs for over 260 hours without measurable loss of performance and processes plastic types that conventional mechanical recycling cannot handle.
What Is Photocatalysis?
The process is called photocatalysis. A catalyst is exposed to light and triggers chemical reactions that would otherwise require extreme temperatures or electrical current. Solar energy drives the conversion without costly external energy input.
What goes in: pieces of nylon, polyurethane and similar high-performance plastics that end up as unprocessable residue in conventional recycling. Alongside these, sulfuric acid from used car batteries is added as a solvent and reaction accelerant, enabling it to be reused as well. What comes out: hydrogen gas, along with acetic acid and hydrocarbon-rich compounds that can serve as chemical feedstocks.
PhD candidate Xiao Lu, who led the study at the University of Adelaide, described the process to ScienceDaily as "dual-purpose": the system eliminates waste and generates clean energy simultaneously, without sacrificing one for the other.
Why This Matters Now
Two global pressures converge in this approach.
On the plastics side: according to the OECD Global Plastics Outlook, around 460 million tonnes of plastic are produced globally each year. Only 9 percent is recycled. Particularly problematic are engineering polymers such as nylon and polyurethane. For these high-performance plastics, industrial recycling pathways barely exist; they mostly end up incinerated or in landfill.
On the hydrogen side: green hydrogen, produced from renewable energy, currently costs 5 to 11 US dollars per kilogram according to the International Energy Agency (IEA), making it barely competitive with fossil-derived hydrogen at around one dollar. Processes that harvest energy from the material being broken down, because plastics release chemical energy during photocatalytic decomposition, could structurally lower production costs.
Still a Lab Prototype
The process remains a laboratory prototype. The Adelaide reactor's chamber processes grams, not tonnes. For comparison, a mid-sized recycling facility processes several hundred tonnes of material daily.
Similar approaches exist in parallel: a group at the University of Cambridge has shown that photoreactors for plastic and CO2 can operate stably outdoors. The Cambridge work focuses on different plastic types and does not use battery acid as a reaction medium. The Adelaide study adds compatibility with hard-to-recycle polymers and the reuse of spent battery acid as new elements.
To put the hydrogen volumes in context: global hydrogen demand stood at around 97 million tonnes annually in 2023, according to the IEA. Even if photocatalytic plastic recycling were to scale, it could deliver a small but structurally relevant contribution to supply, particularly for decentralized applications in regions with high plastic waste and abundant sunlight.
Three Conditions for Leaving the Lab
For this laboratory success to become industrially relevant, three conditions need to be met.
First, efficiency must hold at scale. Photocatalytic systems frequently lose effectiveness as reaction volume grows, because light yield per unit volume falls. Whether the 260-hour stability at lab scale translates to larger reactors needs systematic testing in the next research phase.
Second, a viable cost model is needed. Plastic as a feedstock is theoretically cheap because it is a waste product. Whether the collection, sorting and chemical preparation of nylon and polyurethane remains competitive against other hydrogen pathways is still open.
Third, investors need regulatory clarity. In many jurisdictions, chemical recycling falls under different frameworks than mechanical recycling. Anyone investing in pilot plants needs multi-year planning certainty before large capital commitments make sense. The research result is real; the path to scale is not yet.