Solvothermal synthesis of Cr2O3 nanocubes via template-free route

Abstract

Cr2O3 nanocubes with porous structure were synthesized by solvothermal method at 150 °C/24 h using potassium dichromate (K2Cr2O7), N, N-dimethyl formamide (DMF) and water. Crystallization of Cr2O3 was noticed at 400 °C. The vibration bands at 564 cm−1 and 629 cm−1 signified to Cr–O stretching of Cr2O3, and the intense Raman peak at 532 cm−1 was assigned to A1g symmetry of Cr2O3. The XPS results show the binding energy of 576.8 eV, and 586.4 eV corresponding to Cr 2p3/2 and Cr 2p1/2, respectively of Cr 2p of Cr2O3 phase. The absorption peaks at 455 nm and 600 nm reflect the d3 electronic transition of Cr3+ ion attributing to 4A2g → 4T1g and 4A2g → 4T2g, respectively. The size of the nanocubes was about 50–200 nm. The BET surface area and total pore volume of 400°C- treated sample were found to be 23 m2 g−1 and 0.18 cm3 g−1, respectively.