Engineering Reusable Sponge of Cobalt Heterostructures for Highly Efficient Organic Pollutants Degradation via Peroxymonosulfate Activation

Abstract

The rational 3D design of affordable cobalt heterostructures with tunable catalytic properties and water phase functionality is highly desirable for advanced oxidation applications. Herein, we demonstrate a new and scalable approach based on thermal-induced phase separation chemistry that allows controllable in situ growth of cobalt oxide (Co 3 O 4 ) nanoflowers onto a self-standing polymer sponge. Detailed characterization revealed that the Co 3 O 4 nanoflowers were uniformly and tightly attached on a mesoporous polymeric network with a surface area of 230.0 m 2 /g and excellent mechanical stability. The catalytic performance of the sponge-like catalyst was evaluated by degradation of model organic compounds (i. e., acid orange 7, AO7) under various operational conditions. The results indicate that complete color removal of AO7 can be achieved in < 2 min, with a > 84% TOC mineralization and negligible cobalt leaching under optimal conditions. The SP-50/PMS system could also effectively remove a broad range of compounds like antibiotic tetracycline, acid orange 52 (typical fluorescent azo-dye), and rhodamine B (a typical basic dye). Time-resolved electron paramagnetic resonance (EPR) data revealed that SO 4 * À and OH * À were the primary oxidative species. Overall results exemplified the advantages of highperformance sponge catalyst for the remediation of organic pollutants from water environment.

Surfactant‐Free and Microporous AlOOH/Al2O3 Nanosheets on TiO2‐Based Nanofibers: A Sustained‐Release Dominated Topotactic Transformation

“…For example, heavy metal pollutants, such as arsenic, cadmium, chromium, and nickel, can cause lung, bladder, kidney, and skin cancers, as well as damage to the nervous, cardiovascular, respiratory, and immune systems [25] . Organic pollutants, such as dyes, also pose serious environmental problems due to their high toxicity and potential accumulation in the food chain [26] . Especially, boehmite has abundant hydroxyl radicals on its surface and is a highly effective and versatile adsorbent for heavy metal ions, inorganic pollutants, organic dyes, and other chemical substances [16,27] …”

“…[25] Organic pollutants, such as dyes, also pose serious environmental problems due to their high toxicity and potential accumulation in the food chain. [26] Especially, boehmite has abundant hydroxyl radicals on its surface and is a highly effective and versatile adsorbent for heavy metal ions, inorganic pollutants, organic dyes, and other chemical substances. [16,27] As shown in Figures 5 and S2-3, the adsorption property of nanosheets-on-nanofibers with different Al-species contents was evaluated using Rhodamine B (RhB, a typical organic dye contaminant with aromatic rings and positive charge) as a model pollutant at pH 7.0 and 25 °C.…”

Highly Efficient Dynamic Degradation of Methylene Blue on Hierarchical Nitrogen/Cobalt‐Co‐Doped Carbonaceous Beads with Diffusion Promoting Nanostructures

“…The spectrum of Co 2p can be divided into plenty peaks. One of which at 775.23 and another near 790.41 eV correspond to metal Co, whose generation mechanism has been discussed in the former. The other peaks with binding energy at 778.26 and 799.27 eV are in line with tetrahedron Co II and octahedron Co II , respectively.…”