Synthesis, catalytic activity, magnetic study and anticorrosive activity of mild steel in HCl 1 M medium of (H3dien)[Cu(NO3)(C2O4)2].2H2O. A redetermination at 100 K

Diethylenetriammonium nitrato-bis(oxalato)cuprate (II) dihydrate (H3dien)[Cu(NO3)(C2O4)2].2H2O (1) was synthesized by wet chemistry method. It was assessed for thermal stability (TG-DTA), single crystal X-ray diffraction, Fourier Transform Infrared spectroscopy (FTIR) and magnetic measurements. 1 crystallizes in the monoclinic system (P21/c), with the parameters: a = 10.1054(5) Å, b = 11.0825(5) Å, c = 14.8238(7) Å, β = 103.516(5)°, V = 1614.2 (1) Å3 and Z = 4. The complex anions are distributed into layers, whilst the self-assembly of the inorganic-organic entities is assured by an intricate hydrogen network. At 413 K, the thermal behavior predominantly consists of the removal of water molecules, while its infrared spectrum displays distinct bands of oxalate, nitrate and diethylenetriamine groups. The catalytic test indicated that complex 1 exhibits a good catalytic activity in nitrophenol isomers (NP) reduction to aminophenols (AP). Moreover, 1 showed a high photocatalytic degradation efficiency 90% at 90 min toward the methylene blue (MB) dye under the UV irradiation. Due to the presence of the heteroatoms in its structure, the examined hybrid material's corrosion-inhibiting action in acidic conditions was more pronounced. •The crystal structure of the complex (H3dien)[Cu(NO3)(C2O4)2].2H2O has been determined by single crystal X-ray diffraction.•The crystals are stable up to 413 K.•Magnetization and a.c. susceptibility as a function of magnetic field and temperature were measured and discussed.•Corrosion inhibition by hybrid material (H3dien)[Cu(NO3)(C2O4)2].2H2O.