Zn1−xCoxWO4 (0≤x≤1) full range solid solution: Structure, optical properties, and magnetism

Abstract A novel full-range solid-solution Zn 1− x Co x WO 4 (0 ≤ x ≤ 1) was successfully developed via a facile one-pot hydrothermal route. The phase structure and microstructure were characterized by X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectra and scanning electron microscopy (SEM). The Zn 1− x Co x WO 4 solid solution possesses similar wolframite crystal structure with the same space group P2/c . Diffuse reflection spectroscopy (DRS) measurements on Zn 1− x Co x WO 4 (0 ≤ x ≤ 1) demonstrated that the optical band gap can be continuously tuned from 3.56 eV to 2.61 eV for direct transition and 1.87 eV for indirect transition, respectively, with increasing x from 0 to 1. Magnetic susceptibility measurements reveal that CoWO 4 has an antiferromagnetic transition at T N = 42 K, whereas Zn 0.5 Co 0.5 WO 4 exhibits paramagnetic behavior. Moreover, CoWO 4 and Zn 0.5 Co 0.5 WO 4 obey the Curie–Weiss law from 200 k down to 50 K, and their effective magnetic moments were determined.