LAUSR

V-VI binary chalcogenides, Sb2Se3 has attracted considerable attention for its applications in thin film optoelectronic devices due to its unique 1D structure and remarkable optoelectronic properties. Herein, we report Sb2Se3 thin film epitaxially grown on the flexible mica substrate through the relatively weak (van der Waals) interaction by vapor transport deposition. The epitaxial Sb2Se3 thin films possess a single (120) out-of-plane orientation and a 0.25° full width at half-maximum of (120) rocking curve from the X-ray diffraction, confirming the high crystallinity of the epitaxial films. The Sb2Se3(120) plane is epitaxially aligned on mica(001) surface with the in-plane relationship of Sb2Se3[2 ̅10]//mica[010] and Sb2Se3[001]//mica[100]. Compared to the photodetector made of nonepitaxial Sb2Se3 film, the photocurrent of the epitaxial Sb2Se3 film photodetector is almost doubled. Furthermore, due to the flexibility and high sensitivity of the epitaxial Sb2Se3 film photodetector on mica, it has been successfully employed to detect the heart rate of a person. These encouraging results will facilitate the development of epitaxial Sb2Se3 film-based devices and the potential applications in wearable electronics.