Tuning manganese (III) species in manganese oxide octahedral molecular sieve by interaction with carbon nanofibers for enhanced pollutant degradation in the presence of peroxymonosulfate

Dong

et al. 2020

ACS Appl. Nano Mater.

Three 1D hollow tubelike catalysts with different morphologies were prepared via the technology of electronspinning and pyrolysis of metal−organic frameworks (MOFs). Based on the different growth position of MOFs, three samples were named as In-PBA/PAN, Out-PBA/PAN, and Mixed-PBA/ PAN. After a process of calcination, the well-dispersed In-CoMnO x /MnO y , the cube-stacked Out-CoMnO x /MnO y , and the particle-agglomerated Mixed-CoMnO x /MnO y catalysts were obtained, respectively. For the catalytic combustion of toluene, In-CoMnO x /MnO y catalyst showed the best catalytic performance (T 90 = 200 °C). It had no significant loss of performance within a 40 h thermal stability run. Simultaneously, it also had a relatively good cycling stability and moisture resistance. The catalytic combustion activity was analyzed through a series of characterizations. It was found that the 1D bead chainlike In-CoMnO x /MnO y catalyst could lead to a stronger bimetal synergy effect, more oxygen vacancies, and more weak acid sites compared with the other two samples.

Section: Resultsmentioning

confidence: 97%

Mn-Polyacrylonitrile Nanofibers Decorated with Co-Metal—Organic Frameworks as Precursors of CoMnO_x Catalysts for the Combustion of Toluene

Dong

et al. 2020

ACS Appl. Nano Mater.

“…Another study by Wang et al [57] showed the use of manganese oxides/carbon nanomaterials in dye contaminated-water treatment which were fabricated via reflux method using carbon nanofibers (CNFs) and cryptomelane manganese oxide type octahedral molecular sieves (OMS-2). Acid Orange 7 dye (AO7) undergoes degradation using the prepared composites through peroxymonosulfate (PMS) activation.…”

Section: Reflux Methodsmentioning

confidence: 99%

“…With an increased quantity of low valent manganese species, there is a synergetic and force multiplier effect between OMS-2 and CNFs at an optimum ratio which results in the enhanced degradation of the dye. Structure and performances intricately depend on refluxing time and amount of CNFs, as it has been observed that higher CNFs ratios or extended refluxing time diminish the structure and catalytic activity of OMS-2 [57].…”

Section: Reflux Methodsmentioning

confidence: 99%

Manganese Oxide Nanoparticles: An Insight into Structure, Synthesis and Applications

2023

Manganese oxide nanoparticles with different crystal phases, morphologies, and structural diversity along with their exceptional properties like high specific surface area, a high fraction of surface atoms, non‐toxic nature, and excellent redox properties are drawing attention for various applications in storage science, especially in the batteries, super‐capacitors, energy conversion, and the environmental catalysis field. Precise control of particle size, morphology, surface area, Mnx+ oxidation state, etc. is the utmost important aspect to explore their application to the full potential. Here, the emphasis is on the recent trends in manganese oxide research – structure, synthesis, and applications. The structure of numerous crystalline phases of manganese oxide nanoparticles are summerized and several facile chemical synthesis processes to achieve the desired crystalline/amorphous structure are discoursed. Temperature and different synthesis conditions dependent phase transformations of β‐MnO2, α‐Mn2O3, and Mn3O4 from α‐MnO2 are discussed as well. The pragmatic approach directs that the application field is mostly controlled by the morphologies.

“…CNFs are attractive for membrane water purification due to their relatively simple synthesis, chemical stability, and the low cost of CNFs with high specific area make them good candidates for the removal of pollutants mainly because of low diameter (below 100 nm) and high aspect ratio [ 67 ]. They possess the ability to remove toxic metals due to the multiple interactions that could be realized (for example, π–π interaction, electrostatic interaction, and surface complexation) [ 68 ]. In addition, they have a positive effect on the removal of organic substances.…”

Section: Carbon Nanofibersmentioning

confidence: 99%

Recent Advances on Membranes for Water Purification Based on Carbon Nanomaterials

et al. 2022

Every year the problem of water purification becomes more relevant. This is due to the continuous increase in the level of pollution of natural water sources, an increase in the population, and sharp climatic changes. The growth in demand for affordable and clean water is not always comparable to the supply that exists in the water treatment market. In addition, the amount of water pollution increases with the increase in production capacity, the purification of which cannot be fully handled by conventional processes. However, the application of novel nanomaterials will enhance the characteristics of water treatment processes which are one of the most important technological problems. In this review, we considered the application of carbon nanomaterials in membrane water purification. Carbon nanofibers, carbon nanotubes, graphite, graphene oxide, and activated carbon were analyzed as promising materials for membranes. The problems associated with the application of carbon nanomaterials in membrane processes and ways to solve them were discussed. Their efficiency, properties, and characteristics as a modifier for membranes were analyzed. The potential directions, opportunities and challenges for application of various carbon nanomaterials were suggested.