A novel octamolybdate‐based organic–inorganic hybrid as photo‐Fenton‐like catalyst for degradation of methylene blue
Feng Jiang, Qian‐Qian Liu, Zi‐Wei Cui, Shuang Shi, Jian‐Ying Long, Xiuli Wang, Bao‐Li Fei
Abstract
A γ‐Mo 8 O 26 ‐based organic–inorganic hybrid [Cu 2 (L) 2 (γ‐Mo 8 O 26 ) 0.5 (H 2 O)]•H 2 O (CuLMo 8 ) [L = 5‐(pyrimidyl)tetrazolate] was hydrothermally synthesized and fully characterized by various spectral techniques. In the crystal structure of CuLMo 8 , the μ 2 ‐bridging γ‐Mo 8 anion coordinates with Cu ions to extend into a 2D network. CuLMo 8 displayed excellent photo‐Fenton‐like catalyst properties for MB degradation under UV light irradiation. Complete decolorization of MB solution was finished in 5 min, and the degradation rate reached 97.9% in 7 min. The degradation rate of the present system was much higher than that of similar systems in the literature. The synergistic effect of CuLMo 8 and H 2 O 2 was the fundamental reason for the high degradation rate. Initial pH value and concentration of MB solution, catalyst dosage, and concentration of H 2 O 2 were the main factors to affect the degradation rate. Hydroxyl ( • OH) and superoxide ( • O 2 H/O 2 •‐ ) radicals were the major reactive species to degrade MB molecules. Moreover, the total organic carbon (TOC) removal was about 37.5% in 3 h, indicating mineralization and decolorization did not take place at the same time. The possible MB degradation pathway was deduced depending on the data gained. In view of the high catalytic efficiency, repeated use, and no need to adjust the pH value of MB solution, this heterogeneous catalyst might have potential to deal with practical wastewater.