The reaction of flexible bis(imidazole) ligand and 1,2-bis(imidazol-1’-yl)methane(bimm) with Co(Ⅱ) salt under ionothermal method resulted in the formation of a new coordination polymer {[Co(bimm)3]·(PF6)2}n(1). X-ray single-crystal diffraction determination reveals that 1 crystallizes in the triclinic P1 space group, with a = 8.647(6), b = 12.092(9), c = 14.967(11) , α = 88.912(8), β = 81.199(8), γ = 89.395(8)°, V = 1546(2)3, Z = 2, Mr = 793.39, Dc = 1.704 Mg/m3, μ = 0.768 mm-1, F(000) = 798, the final R = 0.0626 and w R = 0.1634 for 4319 observed reflections with Ⅰ > 2δ(Ⅰ). In compound 1, the Co(Ⅱ) ion is connected to another Co(Ⅱ) by two bimm ligands to form 1D double chains which are further linked by bimm ligands to form a 2D wavelike layer. Topologically, the structure of 1 represents a uninodal 2D 4-connected sql/Shubnikov tetragonal plane net. Moreover, thermogravimetric analyses and photocatalytic property for 1 have also been investigated.