A 2D Cu@TiO 2 composite with a porous and crystalline structure was successfully synthesized via one-step and low-temperature calcination of a 1D Cu-based coordination polymer (Cu-CP), namely [Cu 2 (3-dpha)(1,4-NDC) 2 (H 2 O) 3 ] n (3-dpha = N , N '-bis(3-pyridyl)adipamide and 1,4-H 2 NDC = 1,4-naphthalenedicarboxylic acid). Moreover, the Cu@TiO 2 membrane was fabricated by a simple filtration of the as-grown Cu@TiO 2 composite. Compared with the benchmark TiO 2 photocatalyst, the Cu@TiO 2 composite material with high specific surface area and reduced photogenerated electron-hole ratio exhibited good photodegradation activity and durability for gentian violet (GV), which could be attributed to the combined effect of co-doping of Cu and TiO 2 structure. Furthermore, the ˙OH and ˙O 2 - radicals were predicted to dominate the photocatalytic process. Therefore, this new efficient photocatalyst is a promising candidate for efficient and selective photodegradation of organic pollutants.