Thermal Catalytic Degradation toward Organic Dyes RhB and MB by Dawson-Type Polyoxometalate-Based Metal-Organic Framework

A three-dimensional microporous Dawson-type polyoxometalate-based metal-organic framework (POMOF) [Cu3(H2O)6(P2W18O62)2(3-dpye)6]·28H2O [3-dpye = N,N′-bis(3-pyridinecarboxamide)-1,2-ethane] were further optimized and obtained by adjusting the synthesis conditions. It was well characterized systematically and used as thermal catalyst to explore the degradation of organic dyes rhodamine B (RhB) and methylene blue (MB) under different H2O2 dosage, pH and temperature. The possible catalytic mechanism and role of H2O2 in the catalytic process was proposed. Under the optimal reaction conditions (60°C, neutral conditions), the degradation efficiency of RhB and MB within 50 min was 98.46 and 99.74%, respectively. The good stability and repeatability of title POMOF make it a promising material for thermal catalytic treatment of RhB and MB in sewage.