Self-Accelerating Interfacial Catalytic Elimination of Gaseous Sulfur-Containing Volatile Organic Compounds as Microbubbles in a Facet-Engineered Three-Dimensional BiOCl Sponge Fenton-Like Process

Abstract

The elimination of gaseous sulfur-containing volatile organic compounds (S-VOCs) by a microbubble-assisted Fenton-like process is an innovative strategy. Herein, we established a microbubble-assisted Fenton-like process to eliminate malodorous microbubble CH 3 SH as representative gaseous S-VOCs, in which BiOCl nanosheets loaded on a three-dimensional sponge were exposed to (001) or (010) facets and induced Fenton-like interface reactions. Intriguingly, the microbubbleassisted Fenton-like process significantly removed 99.9% of CH 3 SH, higher than that of the macrobubble-assisted Fentonlike process (39.0%). The self-accelerating interfacial catalytic mechanism was in-depth identified by in situ ATR-FTIR, PTR-TOF-MS, EPR, and DFT computational study. The extraordinary elimination performance of microbubble-assisted Fenton-like process lies in the enhancing dissolution/mass transfer of gaseous CH 3 SH in the gas/liquid phase and the tight contact between CH 3 SH-microbubbles and 3D-BiOCl sponge due to the low rising velocity (0.13 mm s −1 ) and negative charge (−45.53 mV) of CH 3 SH-microbubbles, as well as the effective generation of 1 O 2 by activating the enriched dissolved oxygen in CH 3 SH-microbubble via effective electron-polarized sites on 3D-BiOCl sponge. Furthermore, CH 3 SH-microbubbles transferred electrons to H 2 O 2 through electron-rich oxygen vacancy centers of the 3D-BiOCl sponge to generate more •OH, thus achieving excellent elimination performance. Overall, this study demonstrates the enhanced self-accelerating interfacial catalytic elimination by S-VOC microbubble and provides the underlying mechanisms.

Boosting Fenton-like Catalysis via Electron Tunneling-Based C–Co Charge-Transfer Bridge in Nitrogen-Doped Cobalt@Carbon Nanotube-Grafted Carbon Polyhedron

“…To distinguish the contributions of various reactive species in the Co@NCNT/NC+H 2 O 2 system, quenching experiments were performed , Compared with the results of the experiment in the control conditions (Figure a), TBA markedly obstructed BPA conversion.…”

“…To distinguish the contributions of various reactive species in the Co@NCNT/NC+H 2 O 2 system, quenching experiments were performed. 15 tert-Butanol (TBA), p-benzoquinone (p-BQ), and furfuryl alcohol (FFA) were used as chemical scavengers of • OH, • O 2 − , and 1 O 2 , respectively. 33,51 Compared with the results of the experiment in the control conditions (Figure 5a), TBA markedly obstructed BPA conversion.…”

“…Meanwhile, the rate-determining step that the conversion from the oxidation state to the reduction state still presents a challenge for Fenton-like catalysts. , Recent research has shown that electron transfer can be accelerated in heterogeneous Fenton-like processes triggered by using light, electricity, ultrasonic-assisted excitations of electrons and adjusting the electron structure of the catalyst to improve the utilization of electrons. , Among them, constructing dual reaction centers composed of electron-rich/poor centers has been acknowledged as a more effective approach to optimize the electronic properties of catalysts. Generally, electron-rich centers provide electrons for H 2 O 2 activation, while electron-poor centers receive electrons as electron acceptors and, simultaneously, reimburse electron-rich centers through transmission channels for Fenton-like catalysis. − Our recent studies have shown that the construction of dual-reaction-centers on the BiOX (X = Cl and I) interface can greatly induce the surficial/interfacial electron transfer and achieve the selective reduction of H 2 O 2 by reducing the activation energy demands and eliminating the pH constraints. , Hence, regulating the polarized electron distribution of the TM at the surface and interface of Fenton-like catalysts to promote the generation of ROS to achieve an optimized catalytic performance is highly desirable.…”

“…11−13 Our recent studies have shown that the construction of dual-reactioncenters on the BiOX (X = Cl and I) interface can greatly induce the surficial/interfacial electron transfer and achieve the selective reduction of H 2 O 2 by reducing the activation energy demands and eliminating the pH constraints. 14,15 Hence, regulating the polarized electron distribution of the TM at the surface and interface of Fenton-like catalysts to promote the generation of ROS to achieve an optimized catalytic performance is highly desirable. Actually, the construction of heterostructures by encapsulating transition metal nanoparticles (TM-NPs) in the graphite carbon layer can further promote Fenton-like catalysis, because the work function, electron configuration, and density of states at the Fermi level of the metal species can be optimized by the electron tunneling effect at the composite interface.…”

Electron Transfer Trade-offs in MOF-Derived Cobalt-Embedded Nitrogen-Doped Carbon Nanotubes Boost Catalytic Ozonation for Gaseous Sulfur-Containing VOC Elimination

“…Methyl mercaptan (CH 3 SH), one of the typical gaseous sulfur-containing volatile organic compounds (S-VOCs) with high toxicity (carcinogenic, mutagenic, and teratogenic properties) and corrosiveness, is a representative odorous gas with a very low odor detection threshold of around 0.4 ppb/v. , Elimination of harmful S-VOCs to nontoxic CO 2 and SO 4 2– has significant environmental implications. To remove CH 3 SH, numerous methods have been investigated, including adsorption, biological elimination, photocatalytic oxidation, and catalytic ozonation process .…”