Discriminating the Active Ru Species Towards the Selective Generation of Singlet Oxygen from Peroxymonosulfate: Nanoparticles Surpass Single‐Atom Catalysts

Abstract

Singlet oxygen (1O2) is an exceptional reactive oxygen species in advanced oxidation processes for environmental remediation. Despite single‐atom catalysts (SACs) representing the promising candidate for the selective generation of 1O2 from peroxymonosulfate (PMS), the necessity to meticulously regulate the coordination environment of metal centers poses a significant challenge in the precisely‐controlled synthetic method. Another dilemma to SACs is their high surface free energy, which results in an inherent tendency for the surface migration and aggregation of metal atoms. We here for the first time reported that Ru nanoparticles (NPs) synthesized by the facile pyrolysis method behave as robust Fenton‐like catalysts, outperforming Ru SACs, towards efficient activation of PMS to produce 1O2 with nearly 100% selectivity, remarkably improving the degradation efficiency for target pollutants. Density functional theory calculations have unveiled that the boosted PMS activation can be attributed to two aspects: (i) enhanced adsorption of PMS molecules onto Ru NPs, and (ii) decreased energy barriers by offering adjacent sites for promoted dimerization of *O intermediates into adsorbed 1O2. This study deepens the current understanding of PMS chemistry, and sheds light on the design and optimization of Fenton‐like catalysts.

Electrocatalytic Generation of Singlet Oxygen via ROS-Mediated Redox Chain Reaction for Efficient Disinfection

“…17,18 Electrocatalysis (EC) can be used to produce 1 O 2 more easily by electrical excitation but often requires the addition of a precursor, such as cathodically exciting peroxomonosulfate and anodically exciting ferrocene. 19 Alternatively, in the presence of a chlorinated electrolyte, hydrogen peroxide (H 2 O 2 ) is generated in situ as a 1 O 2 precursor, but harmful chlorine-containing byproducts are produced, thereby reducing the production of 1 O 2 . 20 Therefore, for the highly selective production of 1 O 2 by EC, there is still an urgent need to increase the in situ generation of 1 O 2 precursors and reduce or eliminate the generation of harmful byproducts.…”

“…The photosensitization strategy applies photosensitizers such as molecular dyes or quantum nanodots via absorption of visible or UVA light. , Enzymatic reactions of peroxidases and oxygenases can produce 1 O 2 , however, require the use of intracellular environments with stringent pH and temperature conditions in biological systems . Photosensitization and enzymatic reactions rely on stringent external conditions and are difficult to produce on an industrial scale. , But electrocatalysis (EC), a highly automated and convenient technology, can provide easier access to the production of 1 O 2 . , Electrocatalysis (EC) can be used to produce 1 O 2 more easily by electrical excitation but often requires the addition of a precursor, such as cathodically exciting peroxomonosulfate and anodically exciting ferrocene . Alternatively, in the presence of a chlorinated electrolyte, hydrogen peroxide (H 2 O 2 ) is generated in situ as a 1 O 2 precursor, but harmful chlorine-containing byproducts are produced, thereby reducing the production of 1 O 2 .…”

Design of Environmental-Friendly Carbon-Based Catalysts for Efficient Advanced Oxidation Processes

“…The following supporting information can be downloaded at: , Figure S1: N 2 adsorption-desorption isotherm plot of Co-C/SiO 2 ; Table S1: BET comparison between Co-C/SiO 2 and other catalysts; Table S2: Comparison of the binding energy and content of each element of Co-C/SiO 2 before and after the reaction; Table S3: Comparison between Co-C/SiO 2 and other Fenton-like catalysts for 1 O 2 yield. References [ 52 , 53 , 54 , 55 , 56 , 57 , 58 ] are cited in the supplementary materials.…”