Study on visible photocatalytic activity of an oxalate-extended Co(II) coordination polymer.

A two-dimensional (2D) coordination polymer [Co(ox)(bpy)] 1 (ox = oxalate, bpy = 4,4'-bipyridine) was prepared by hydrothermal synthesis using CoCl₂⋅5H₂O, oxalic acid, bpy as raw material. Compound 1 is a 2D structure extended by ox and bpy, and it has excellent visible photocatalytic performance. The photocatalytic efficiency of compound 1 could reach up to 98.13% with pH = 10 when two drops of H₂O₂ were added to methylene blue. The photocatalytic degradation results could be described by the first-order kinetic. Besides, after five cycles, the degradation efficiency decreased only 4.11% (without H₂O₂) and 5.22% (with H₂O₂). Meanwhile, the solid fluorescence and UV-Visible diffuse reflection of compound 1 were also studied. What's more, the visible light photo- catalytic mechanism of compound 1 was analyzed more clearly by free radical trapping experiment and Mott-Schottky curve. [ABSTRACT FROM AUTHOR]