Stable Black Phosphorus Encapsulation in Porous Mesh-like UiO-66 Promoted Charge Transfer for Photocatalytic Oxidation of Toluene and o-Dichlorobenzene: Performance, Degradation Pathway, and Mechanism

Abstract

This work presents a new strategy to enhance the charge transfer from Zr atoms in UiO-66 to black phosphorus (BP) via an atomic-level charge-transfer channel provided by Zr–P bonds for photocatalytic degradation of toluene and o-dichlorobenzene. The formation of Zr–P bonds is the key to covering BP with the UiO-66 encapsulation layer and improving the charge-transfer capability of BP–UiO, which is also verified by a series of characterization and theoretical calculations. The hydrophilic porous mesh-like UiO-66 encapsulation layer endows BP–UiO with enhanced visible-light-harvesting ability, charge transport capability, and photocatalytic activity. Additionally, BP–UiO demonstrates the promoted redox/acidity properties, significantly improving catalytic activity for the degradation of toluene and o-dichlorobenzene even in the presence of water. The degradation pathways of contaminants are investigated via the study of transient variations by in situ infrared (IR) methods, refined by the static analysis of intermates accumulated on the BP–UiO surface by gas chromatography–mass spectrometry (GC–MS). The electron transfer via bond construction and the combination of in situ IR and GC–MS are expected to provide a more complete theoretical basis for environmental catalysis.

The composing effect of bismuth on titania hollow microspheres for their visible-light photocatalytic activity

“…5a, all the samples show type IV isotherms with two hysteresis loops at a low relative pressure of 0.6–0.8 and a high relative pressure of 0.8–1, respectively, signifying that Bi-composed TiO 2 is expressed as a mesoporous material, implying bimodal pore size distributions. 56,57 As further confirmed in Fig. 5b, bimodal peak distributions are observed, that is, smaller mesopores with weak peak pore diameters of 3.0–5.0 nm and bigger mesopores with strong peak pore diameters of 5–50 nm.…”

Lewis acid-triggered photocatalytic hydrogen peroxide production in an aluminum-based metal–organic framework

“…MOFs have attracted interest in photocatalysis due to high surface area, and easy functionalization. 1,2 The organic linker of MOF photocatalysts acts as an antenna to capture light, which excites electrons from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) of the organic linker. The photoexcited electrons further relay to inorganic nodes of the MOFs through linkerto-metal charge transfer (LMCT), resulting in a reduction of metal ions in inorganic nodes, which finally induce various photoredox reactions (e.g., H 2 production, CO 2 reduction, and H 2 O 2 production).…”

Degradation of tetracycline by persulfate oxidation promoted by iron-modified biochar

“…The high surface area of Fe@BC facilitates the adsorption and contact of catalysts with PMS and pollutants and provides more exposed active sites for catalytic reactions. 13,14…”

“…Biochar also has a large specific surface area, which can provide more adsorption sites. [13][14][15] However, shortcomings, such as difficulty in recycling and reuse, fewer surface active sites, and low graphitization content, still limit its further promotion. 9,10 In recent years, magnetic transition metals (Fe, Co, Ni) or their oxides compounded with biochar to prepare magnetic biochar have received considerable attention.…”