Quantum dots (QDs) have long been heralded as the cornerstone of next-generation display technologies due to their exceptional color purity and size-tunable emission. However, the bulky long-chain ligands required to stabilize these nanocrystals often create significant "steric hindrance," leaving behind unpassivated dangling bonds that act as energy traps. These surface defects trigger non-radiative recombination, which severely limits the efficiency and longevity of QD light-emitting diodes (QLEDs), a challenge that becomes even more acute as devices are miniaturized for ultra-high-resolution applications.
To overcome this fundamental hurdle, Professors Fushan Li and Hailong Hu from Fuzhou University have developed a universal strategy for the chemical reconstruction of QD surfaces. By employing zirconium acetylacetonate (Zr(acac)₄)—a small molecule featuring high mobility and strong coordination capability—the research team successfully "repatched" the residual surface defects that traditional larger ligands fail to access. The findings of this study were recently published in the prestigious journal Nano Research on June 24.
The acetylacetonate anions can effectively overcome the spatial obstacles imposed by long-chain ligands, diffusing to the QD surface to strongly anchor onto unsaturated zinc atoms," explains Prof. Hailong Hu. "This precise chemical repair not only boosts the photoluminescence quantum yield of the QDs but also significantly suppresses exciton quenching at QD/ZnO interfaces."
The impact of this reconstruction on device performance is transformative. The optimized QLEDs achieved a record-breaking external quantum efficiency (EQE) of 34.3%. Importantly, the treated devices demonstrated a T 95 operational lifetime of 19,450 hours at 1,000 cd/m 2 , nearly four times longer than that of unmodified devices.
Beyond raw efficiency, the research addresses the critical "performance gap" encountered in micro-display applications. As pixel dimensions shrink to achieve higher resolutions, the resulting inhomogeneous electric fields typically exacerbate the negative effects of surface defects. The Fuzhou University team demonstrated that their ligand reconstruction strategy effectively mitigates this degradation, yielding a champion EQE of 25.3% in devices with a pixel density of approximately 10,000 PPI.
Other contributors include Kuibao Yu, Zhihan Lin, Chao zhong, Haolin Luo, Hao Liu, Jiahao Wang and Kai Xie from the Institute of Optoelectronic Technology at Fuzhou University in Fuzhou, China; Yongsheng Yu and Yanbin Liu from Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China in Fuzhou, China.
This work was supported by the National Key Research and Development Program of China (2022YFB3606502).
DOI Link:
https://doi.org/10.26599/NR.2026.94908717
About Nano Research
Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 8,000 articles. In 2025 InCites Journal Citation Reports, its 2025 IF is 9.4 (8.3, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.
Nano Research
Breakthrough in Quantum Dot Surface Defect Repair: Enabling Ultra-High Efficiency and Long-Life QLEDs
24-Jun-2026