RESUMO
In this study, a flower-like BiVO4/MIL-101-NH2 composite is synthesized by a facile and surfactant-free process. The -COO--Bi3+ ionic bond construction was conductive to enhance the interface affinity between BiVO4 and MIL-101-NH2. Due to the highly efficient light capture and sufficient electron traps induced by oxygen vacancies and the formation of a heterostructure, the improved separation and transportation rates of charge carriers are realized. In addition, the MIL-101-NH2/BiVO4 composite is favorable for Cr(VI) photocatalytic removal (91.2%). Moreover, FNBV-3 (Fe/Bi = 0.25) also exhibited an excellent reusability after five cycles.
RESUMO
The design and construction of a photocatalyst with a heterostructure are a feasible and effective way to enhance the catalytic performance. Herein, a specially designed composite based on MIL-125-NH2 and BiVO4 was prepared and used for wastewater treatment. In the hybrid MIL-125-NH2@BiVO4, MIL-125-NH2 was uniformly dispersed on the BiVO4 surface. There is a high affinity between MIL-125-NH2 and BiVO4 due to the lattice defects. Under visible light irradiation, the catalytic activity of the as-prepared composite was evaluated by the degradation of various dyes such as malachite green, crystal violet, methylene blue, and Congo red. Nearly 98.7, 99.1, and 41.0% of the initial MG, MB and Cr(VI) were respectively removed over the optical sample of BVTN-5, demonstrating that the hybrid holds great promise for practical applications. Moreover, the composites can be recycled and reused with good stability after five consecutive cycles. The mechanism was proposed and discussed in detail. This work will shed light on the construction of MOF-based composites for efficient photocatalysis.
