Effects of Co and Ni on visible light photocatalytic properties of layered double hydroxide films

Altering the composition of layered double hydroxides (LDHs) is an effective method for changing their properties. In this study, LDH films with different compositions were fabricated on conductive cloth by using a hydrothermal method. Electron microscopy, X-ray diffraction, and UV–vis diffuse reflectance spectroscopy were used to investigate the morphology, crystal structure, and optical properties of the LDH films. The photocatalytic activity of LDHs with different compositions in the degradation of methyl orange was investigated under visible light irradiation. Our experimental results show that the reductive sites (Ni(II) and Co(II)) of LDHs and the conductive substrate improve the separation of photogenerated charges and prevent the particle aggregation of LDHs. LDH films (NiAl-LDHs, NiFe-LDHs, and CoAl-LDHs) with reductive sites (Ni(II) and Co(II)) exhibit higher visible light photocatalytic performance.