A team of researchers from the School of Energy and Chemical Engineering at UNIST, jointly led by Professors Sung-Yeon Jang, Jungki Ryu, and Ji-Wook Jang, in collaboration with Professor Sang Kyu Kwak from Korea University, have achieved remarkable advancements in the steadiness and efficiency of perovskite solar cells. Their groundbreaking work not only paves the way in which for the commercialization of perovskite solar cells (PSCs), but additionally offers significant potential in green hydrogen production technology, ensuring long-term operation with high efficiency.
Perovskite solar cells (PSCs) have garnered attention attributable to their reduced toxicity and broad light absorption capabilities, making them highly promising for photovoltaic applications. Nonetheless, the presence of inherent ionic vacancies in tin-lead halide perovskites (TLHPs) has posed challenges, resulting in accelerated device degradation through inward metal diffusion.
To handle this challenge, the research team developed a chemically protective cathode interlayer using amine-functionalized perylene diimide (PDINN). By leveraging its nucleophilic sites to form tridentate metal complexes, PDINN effectively extracts electrons and suppresses inward metal diffusion. The novel solution-processed PDINN cathode interlayer has showcased remarkable performance in stabilizing TLHP-based photovoltaic (PV) and photoelectrochemical (PEC) devices.
The PV device achieved a powerful efficiency of 23.21%, with over 81% retention after 750 hours of operation at 60 °C, and greater than 90% retention after 3100 hours at 23 ± 4 °C. Moreover, the TLHP-based PEC devices, coupled with biomass oxidation, exhibited a record-high bias-free solar hydrogen production rate of 33.0 mA cm−2, roughly 1.7-fold higher than the goal set by the U.S. Department of Energy for one-sun hydrogen production.
Their progressive design of the cathode interlayer has successfully demonstrated the immense potential of TLHPs for efficient and stable photoconversion.
“We now have dramatically increased the long-term stability of tin-lead PSCs,” explained Professor Jang. “Our goal isn’t only to convert light energy into electricity but additionally to develop eco-friendly methods for producing basic chemicals, corresponding to hydrogen, which form the muse of assorted industries.”
The research findings have been published online in Advanced Energy Materials on November 30, 2023. The study received support from the National Research Foundation of Korea (NRF) under the Ministry of Science and ICT (MSIT).
