Researchers from Hebei University of Technology, Kunming University of Science and Technology, Macau University of Science and Technology and CNRS have reported a new stabilization approach for perovskite solar cells. The team demonstrates that incorporating a hindered amine light stabilizer into inverted perovskite solar cells effectively blocks photo-induced decomposition pathways.
Using this approach, the researchers fabricated devices that achieved a certified power conversion efficiency exceeding 26% while maintaining performance under prolonged light exposure - offering a promising route toward durable, high-performance perovskite photovoltaics.
The proposed hindered amine stabilization strategy (HASS) operates through a dual mechanism. Under illumination, the hindered amine absorbs light energy and forms nitroxyl radicals that catalytically neutralize superoxide species generated within the perovskite layer. By removing these highly reactive radicals before they can attack organic cations or Pb–I bonds, the strategy suppresses the primary chemical trigger of light-induced degradation. Importantly, the radical-scavenging process is regenerative, allowing continuous protection during device operation.
In parallel, functional groups within the hindered amine molecule coordinate with under-coordinated lead ions and iodine vacancies at grain boundaries and surfaces. This chemical interaction passivates electronic trap states, enlarges perovskite grain size, smooths film morphology, and reduces non-radiative recombination.
Spectroscopic and electrical analyses confirm lower trap densities, longer carrier lifetimes, and improved energy-level alignment at device interfaces. Together, these effects enable inverted perovskite solar cells fabricated under ambient conditions to achieve a champion efficiency of 26.74%. Unencapsulated devices retain over 95% of their initial efficiency after more than 1,000 hours of continuous light aging - demonstrating a rare combination of record efficiency and operational stability.
“This work shows that light instability in perovskite solar cells is not an unavoidable materials problem, but a chemically addressable one,” the researchers note. By targeting both reactive radicals and interfacial defects, the hindered amine approach offers a unified solution rather than a collection of incremental fixes. The authors emphasize that the strategy is compatible with existing device architectures and scalable fabrication methods, making it particularly relevant for translating laboratory advances into commercially viable photovoltaic technologies.
The demonstrated stabilization strategy could accelerate the commercialization of perovskite solar cells, especially for applications requiring long-term exposure to sunlight, such as building-integrated photovoltaics and tandem solar modules. Beyond perovskites, the concept of combining radical scavenging with defect passivation may be applicable to other light-sensitive optoelectronic materials. By reframing stability as a controllable chemical process rather than a structural limitation, this work opens new pathways for designing durable, high-efficiency solar technologies that bridge the gap between laboratory performance and real-world deployment.
