CsLaTa2O7/Na2Ta2O6 heterostructure photocatalyst was constructed via the growth of pyrochlore⁃type Na2Ta2O6 particles on the surface of layered structure CsLaTa2O7 using its metastable property through hydrothermal method. The CsLaTa2O7/Na2Ta2O6 was characterized by XRD, SEM, TEM, UV⁃Vis spectroscopy and PL spectroscopy. The results show that the CsLaTa2O7/Na2Ta2O6 heterostructure can effectively inhibit the recombination of photogenerated electrons and holes, and its photocatalytic performance under UV light is significantly higher than that of single phase. Methylene blue can be completely degraded within 10 min under the illumination of ultraviolet light.

In this paper, layered titanic acid H1.07Ti1.73O4•H2O (HTO) was treated with hydrogen peroxide solution to achieve the hydrogen peroxide intercalation and modification of HTO. The hydrogen peroxide molecules entered into the interlayer of TiO6 octahedral layer, forming a peroxytitanium coordination bond with Ti4+ in the layer, which increased the negative charge density of the TiO6 layers. XRD, SEM, TEM, XRF, FT⁃IR and other methods were used to characterize the samples before and after ion exchange. The ion exchange experiments show that compared with HTO, the ion exchange efficiency and ion exchange capacity of H2O2⁃modified HTO are greatly enhanced. And the main reason is that the introduction of H2O2 leads to the increase of negative charge of TiO6 octahedral layers.