Title: Nanoscale correlation of single-molecule reactivity and charge carrier dynamics in a two-dimensional layered InSe photocatalyst

Authors: Li-Wen Wu, Pin-Tian Lyu, Ran Zhang, Keng Chen, Li Zuo, Dongliang Song, Zhen-Zhen Feng, Ya-Ting Nie, Xiaodong Cheng, Teng-Xiang Huang*, Bin Kang*, Ning Fang*

Abstract: Photogenerated charge carriers play a pivotal role in driving chemical transformations during photocatalysis. However, the structural complexity of photocatalysts presents challenges in establishing nanoscale correlation between carrier dynamics and photocatalytic activity. Here we integrate single-molecule fluorescence imaging with femtosecond interferometric scattering microscopy to resolve the carrier dynamics and specific reaction rate of hydroxyl radical oxidation at the individual structural features (that is, basal plane, edge and wrinkle) in 2D layered indium selenide (InSe). We find a positive linear correlation between the specific reaction rate and the carrier lifetime, but only a weak correlation with the carrier concentration. Moreover, both basal planes and edges exhibit peak lifetimes and specific reaction rates in three-layer InSe. These spatially resolved, correlative single-molecule superlocalization and ultrafast measurements are a powerful tool for investigations of structure–function correlation.

Full-Link: https://www.nature.com/articles/s41929-025-01472-w