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2D materials, semiconductor, photoelectron related image and nano-spectroscopy, synchrotron radiation, Nature
NSRRC User Prof. Yann-Wen Lan and TPS 27A2 team Collaborative Research on 2D MoS2 Published in Nature
2026/10/15
Electronic valence band dispersion measured on a 1H-phase MoS2 bilayer using the TPS 27A2 endstation, providing direct evidence of a direct bandgap
Prof. Yann-Wen Lan from the Department of Physics at National Taiwan Normal University, in collaboration with the NSRRC TPS 27A2 team, has achieved a key breakthrough in the development of two-dimensional (2D) MoS2. The team successfully overcame the conventional physical limits on light-emission efficiency in 2D materials, creating a novel bilayer structure that exhibits both high-efficiency light emission and superior performance. This groundbreaking research has been published in the world’s leading journal Nature.

2D MoS2 is widely recognized as a promising candidate for next-generation semiconductor devices due to its high carrier mobility and excellent electronic properties. However, its limited light-emission efficiency in conventional multilayered stacking (2H MoS2) has long hindered its integration into optoelectronic systems. To address this bottleneck, the research team successfully synthesized 1H stacking bilayer MoS2 with atomically precise alignment. By utilizing the Photoelectron Related Image and Nano-spectroscopy (PRINS) endstation at NSRRC's TPS 27A2, the team confirmed that this unique 1H-stacked bilayer structure retains a direct bandgap—a property previously observed only at the monolayer limit—thereby breaking traditional physical constraints. Further experimental results also demonstrated a significant enhancement in photoluminescence efficiency surpasses that of monolayer counterparts. This work establishes a model system for stacking-engineered quantum materials and underscore its potential for the development of the next-generation optoelectronic devices.