Rb (Dy)-doped SrSn(OH) 6 for the photodegradation of gentian violet

Rb (Dy)-doped hexahydroxy strontium stannate (SrSn(OH) 6 ) was fabricated by a facile hydrothermal route without any surfactants. The doped SrSn(OH) 6 samples were analyzed by X-ray diffraction, electron microscopy, solid diffuse reflectance spectra, X-ray photoelectron spectroscopy, photoluminescence, and electrochemical impedance spectroscopy. 2wt.% Rb (Dy)-doped SrSn(OH) 6 consists of hexagonal SrSn(OH) 6 and tetragonal SnO 2 phases. Rb and Dy exist in the form of rhombohedral Rb 2 Sr(SO 4 ) 2 and cubic Dy 2 Sn 2 O 7 in the 5wt.% and 8wt.% doped SrSn(OH) 6 , respectively. The SrSn(OH) 6 nanorods are completely converted to nanoscale particles with the size of less than 100 nm in the doped products with increasing the Rb (Dy) content from 2wt.% to 5wt.%. The band gap energy of the doped SrSn(OH) 6 is lower than that of the un-doped SrSn(OH) 6 . 2wt.% Rb (Dy)-doped SrSn(OH) 6 shows the band gap with the value of 3.39 eV (Rb doping) and 2.96 eV (Dy doping), respectively. 2wt.% Dy-doped SrSn(OH) 6 shows the most efficient charge separation and transfer performance. Rb (Dy) ions prevent the recombination of the electrons/hole pairs showing better photocatalytic activity toward the gentian violet than the un-doped SrSn(OH) 6 . The light absorption ability of the doped SrSn(OH) 6 can be greatly enhanced which is beneficial for improving the photocatalytic performance of the SrSn(OH) 6 for the photocatalytic degradation of the gentian violet. The Rb (Dy)-doped SrSn(OH) 6 shows higher photocatalytic efficiency than pure SrSn(OH) 6 .