Researchers at the Daegu Gyeongbuk Institute of Science and Technology (DGIST) in South Korea have achieved a record level of efficiency in solar hydrogen production using eco-friendly, heavy-metal-free quantum dots, according to a joint announcement made with Konkuk University on February 27, 2026.
The collaborative team, led by Professors Yang Ji-woong and In Su-il of DGIST’s Department of Energy Science and Engineering, and Professor Kim Jae-Yup of Konkuk University’s Department of Chemical Engineering, detailed their findings in the energy and environmental journal eScience on December 22, 2025. The breakthrough addresses a significant obstacle to the widespread adoption of quantum dot technology: the toxicity of materials traditionally used to achieve high efficiency.
Quantum dots, semiconductor nanocrystals known for their light-absorbing properties, are considered promising materials for next-generation applications including displays and, crucially, photoelectrochemical hydrogen production – a process that uses sunlight to split water into hydrogen fuel. However, most high-efficiency quantum dots contain heavy metals like lead or cadmium, hindering their commercial viability due to environmental and health concerns.
The DGIST-led research focused on copper indium sulfide (CuInS₂), a ternary semiconductor material that does not contain heavy metals. Researchers successfully identified the synthesis mechanism of CuInS₂, enabling precise control over the formation of the quantum dots. This control allowed them to minimize internal defects within the crystals, which previously limited the efficiency of heavy-metal-free alternatives. Advanced analytical techniques, including real-time X-ray scattering analysis, were employed to understand the formation process, according to a release from DGIST.
The team achieved “world-class efficiency” in solar hydrogen production, surpassing previous results for eco-friendly quantum dot systems. Specifically, a quantum dot composition with a 1-to-1 mixture of sulfur and selenium demonstrated the highest photocurrent density. This achievement marks a significant step toward scalable and sustainable hydrogen production, aligning with global decarbonization efforts, as noted by researchers in the field of photocatalysis and solar-driven water splitting.
The development of this technology has attracted significant attention, with the quantum dot-based device demonstrating the highest level of hydrogen production activity to date among eco-friendly quantum dot systems. Dr. Ahn Hyung-joo of the Pohang Accelerator Laboratory contributed to the research through joint efforts with the DGIST team.
As of March 4, 2026, DGIST has not announced plans for immediate commercialization of the technology, but continues to investigate further optimization of the quantum dot synthesis process.
