Construction of MIL-125-NH₂@BiVO₄ Composites for Efficient Photocatalytic Dye Degradation

Abstract

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-NH 2 and BiVO 4 was prepared and used for wastewater treatment. In the hybrid MIL-125-NH 2 @BiVO 4 , MIL-125-NH 2 was uniformly dispersed on the BiVO 4 surface. There is a high affinity between MIL-125-NH 2 and BiVO 4 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.

Growth of villi-microstructured bismuth vanadate (Vm-BiVO4) for photocatalytic degradation of crystal violet dye

“…Aer that, the suspension was magnetically stirred for 30 min in the absence of light to saturate the photocatalyst before light irradiation. 25 During photoreaction, samples were collected at 10 min time intervals and centrifuged to eliminate the photocatalyst particles for awless UV/Vis results. To nd the efficiency of Au@Vm-BiVO 4 , following formula was used: 26…”

Photoelectroactive metal–organic frameworks

“…182 The photodegradation of methylene blue (MB) (Scheme 4) is another concern in wastewater treatment. [187][188][189][190][191][192] For instance, a pristine Cu MOF [Cu(4,4 ′ -bipy)Cl] n constructed from CuCl 2 -$H 2 O and 4,4 ′ -bipyridine (4,4 ′ -bipy) was reported to photodegrade MB (10.0 ppm) in the presence of H 2 O 2 with a rate constant of 1.82 × 10 −2 min −1 and degradation efficiency of 93.93% within 150 min at room temperature under visible light (>420 nm) irradiation. Active species of cOH radicals and photogenerated holes were responsible for the photodegradation.…”

“…Crystal violet (CV) and basic red 2 were photodegraded by a hybrid Cd MOF that was constructed from CdI 195 In addition, MOF-based photocatalysts were also reported to degrade organic dyes like metanil yellow (MY), methyl orange (MO), direct red 23, basic blue 41, malachite green (MG), Congo red (CR), and AB 92 under visible light irradiation. 72,185,190,192,196 3.5.2 Photodegradation of antibiotics. Antibiotics represent another threat in contaminated water although originally used for humans and animals as medical treatments.…”

“…195 In addition, MOF-based photocatalysts were also reported to degrade organic dyes like metanil yellow (MY), methyl orange (MO), direct red 23, basic blue 41, malachite green (MG), Congo red (CR), and AB 92 under visible light irradiation. 72,185,190,192,196…”

The Effect of Ligand-to-Metal Energy Transfer on the Photooxidation Performance of an Isostructural Series of Pyrene-Based Rare-Earth Metal–Organic Frameworks

“…When performing photocatalysis with MOFs, the organic linkers are typically the light harvesting structural component and can work alone as photosensitizers [31][32][33][34] or together with other framework components to facilitate ligand-to-metal charge transfer (LMCT) to the metal node [35][36][37][38] or metal nanoparticles incorporated into the MOF. [39][40][41][42] In the former approach, singlet oxygen ( 1 O2) generation by photosensitizing linkers or ligands in MOFs has been studied for the oxidative detoxification of chemical warfare agents, [43][44][45] production of commodity chemicals, 46 as well as for various biological applications. 47,48 The performance of MOF photosensitizers relies primarily on the identity of the organic linker but can be affected by the identity of the metal nodes due to coupling between electronic energy levels of the organic linker and metal ions.…”