Dynamic behavior of BiVO4 material under mechanical studies.

Abstract The mechanical relaxation technique is applied to investigate the fundamental dynamic behavior of BiVO 4 material. A prominent internal friction peak is observed around 430 K at 1 Hz, which is actually composed of three sub-peaks (P 1 , P 2 and P 3 from low to high temperature). And the associated modulus anomalies can also be found in any of the samples. The peak P 1 with activation energy E 1 ∼ 3.20 eV is probably related to the stress-induced unequal positions of Bi3+ ions; while the main P 2 peak with E 2 = 0.91 eV is associated with a complex mechanism, which originates from the viscous motion of domain walls and the interaction of domain walls with oxygen vacancies; and the responsive P 3 peak is resulted from the ferroelastic–paraelastic phase transition, accompanied by a minimum modulus value. Based on the relaxation process and crystalline structure of BiVO 4 , the motion model of ferroelastic domain walls and transport mechanism of diffusion are suggested. Our results pave the way for better understanding the intrinsic dynamic and multifunctional properties of BiVO 4. Highlights • Pave a novel method for understanding the intrinsic dynamic properties of BiVO 4. • The kinetic behavior has been systematically analyzed under mechanical measurement. • The motion evolution of ferroelastic domains of BiVO 4 is first reported. • The mixed electric/oxide conduction mechanism of BiVO 4 has been well established. [ABSTRACT FROM AUTHOR]