Visible light photostriction in Kagome staircase zinc ortho-vanadate

Abstract

Ferroelectric materials have been widely explored for photostrictive action, but their high performance being limited to ultra violet light demands to look for efficient visible light photostrictive materials. Transition metal vanadates, exhibiting the Kagome structural features besides being active in visible light, are the interesting materials for the photostriction study. Here, we investigate the photostriction of the non-magnetic member zinc ortho-vanadate Zn3(VO4)2 or Zn3V2O8. Corresponding to the photostriction response of ∼10−3 under a 405 nm laser (response time, τ = 5.7 s) and ∼10−4 (τ = 5.8 s) under a 665 nm laser, it exhibits a large photostriction efficiency of ∼10−11 and ∼10−12 m3/W, respectively. Thermal expansion investigation indicates that the non-thermal strain dominants the photostriction of Zn3V2O8 ceramics. The peak shift in x-ray diffraction (XRD) pattern as well as in Raman spectra under external laser irradiance revealing, increased anisotropic distortions with increasing stretching and vibrations in the bonds of ZnO6 octahedrons and VO4 tetrahedrons, is proposed as the underlying mechanism of the photostriction response in Zn3V2O8. The good visible light photostriction, rapid response time, and stability functionalities make it a potential candidate for future generation optoelectronics, such as light driven micro-actuators, robots, relays, and other optomechanical devices.