Fabrication of Efficient Nano-MnO_x/ACF Particle Electrodes and their Application in the Electrooxidation of m-Cresol in the 3-D Electrode System

Abstract

Various metallic oxide nanoparticles supported on commercial activated carbon fibers (M/ACF) were fabricated and employed as particle electrodes to degrade aqueous m-cresol in (three-dimensional) 3-D electrochemical systems. It has been experimentally demonstrated that the ACF loaded with MnO x exhibited relatively higher 3-D electrooxidation performance than other metallic oxides (FeO x , CuO, and SnO2). Several fabricated samples were characterized by N2 adsorption, SEM, TEM, and so forth. The characterization results revealed that MnO x on the ACF samples was mainly composed of MnO2 and Mn2O3 nanoparticles, while the presence of MnO2 might be beneficial for the 3-D electrooxidation. The experimental results proved that the optimal preparation techniques of Mn/ACF were as follows: active component loading: 6% and calcination temperatures: 450 °C, resulting in about average 70% TOC removal. The reaction mechanism was discussed: the electrooxidative degradation process of organic pollutants with MnO x /ACF as particle electrodes was the synergistic effects of MnO x nanomaterials and ACF functional groups.

MnO2‐Based Materials for Environmental Applications

“…Liu et al. [ 288 ] fabricated a MnO 2 /activated carbon‐fiber particle electrode for the electrocatalytic oxidation of m ‐cresol.…”

“…e) Reproduced with permission. [ 288 ] Copyright 2019, American Chemistry Society. f) Schematic diagram of MnO 2 @CuO membrane for catalytic filtration and degradation of methylene blue.…”

“…MnO 2 ‐based materials have shown enormous potential applications in the removal of organic pollutants in various wastewater treatment technologies, including adsorption, catalytic ozonation, photocatalytic oxidation, electrocatalytic oxidation, peroxymonosulfate oxidation, catalytic filtration, and energy harvesting galvanic cell technologies. So far, MnO 2 ‐based materials have shown superior performances in the removal of various organic pollutants in water, such as dye (methylene blue, [ 359–361 ] methyl orange, [ 362,363 ] Rhodamine B, [ 309,364 ] Congo red, [ 365 ] acid fuchsin dye, [ 218 ] crystal violet dye, [ 366 ] acid red 73, [ 367 ] neutral red, [ 368 ] and tartrazin yellow [ 369 ] ), phenolic pharmaceuticals (phenol, [ 66,325,342,370–372 ] bisphenol A, [ 99,275,373–378 ] ibuprofen, [ 295 ] tetrabromobisphenol A, [ 379 ] benzophenone‐3, [ 216 ] 2,4‐dichlorophenol, [ 380 ] 4‐chlorophenol, [ 381 ] and 4‐nitrophenol [ 382 ] ), antibiotics (tetracycline, [ 383 ] ceftiofur, [ 243 ] and lomefloxacin [ 243 ] ), as well as ammonia borane, [ 384 ] amides, [ 385 ] lignin, [ 386 ] peroxymonosulfate, [ 237 ] 17 β‐Estradiol, [ 249 ] m ‐aminophenol, [ 387 ] carbamazepine, [ 388 ] dichloroacetic acid, [ 389 ] p ‐arsanilic acid, [ 390 ] phenylarsonic acids, [ 391 ] m ‐cresol, [ 288 ] oxalic acid, [ 392 ] ciprofloxacin, [ 393,394 ] phenanthrene, [ 246 ] norfloxacin, [ 291 ] etc. ( Table 2 ).…”

“…With its advantages, MnO 2 ‐based materials have shown excellent performances in the treatment of wastewater by electrocatalytic oxidation, which has attracted growing interest in recent years. [ 288,392 ] Liu et al. [ 288 ] fabricated a particle electrode by loading MnO 2 NPs on an activated carbon fiber and formed a 3D electrochemical system for the electrochemical oxidation of m ‐cresol (Figure 21e).…”

“…[ 288,392 ] Liu et al. [ 288 ] fabricated a particle electrode by loading MnO 2 NPs on an activated carbon fiber and formed a 3D electrochemical system for the electrochemical oxidation of m ‐cresol (Figure 21e). The as‐synthesized particle electrode has a large reaction surface area and a high mass transfer rate, which reduces the energy consumption and shows a prospect of industrialization in the short term.…”