Potassium Ferrite as Heterogeneous Photo-Fenton Catalyst for Highly Efficient Dye Degradation

Abstract

In this work, hexagon-shaped potassium ferrite (K2Fe4O7) crystals with different sizes were prepared using the hydrothermal method. The crystals showed a narrow band gap of 1.44 eV, revealed by UV-visible diffuse reflectance spectroscopy, and was thus used as a heterogeneous Fenton catalyst to degrade methylene blue (MB) and crystal violet (CV) in the presence of green oxidant H2O2 under visible-light irradiation. Among the investigated crystals, the as-prepared one with an average size of 20 µm (KFO-20) exhibited better photocatalytic activity due to its high surface area. When it was used as a photo-Fenton catalyst, 100% MB and 92% CV were degraded within 35 min. Moreover, the catalyst maintained high photocatalytic activity and was stable after four continuous cycles. The trapping experiments showed that the active hydroxyl radical (·OH) was dominant in the photo-Fenton reaction. Therefore, this new photo-Fenton catalyst has great potential for the photocatalytic degradation of dye contaminants in water.

Magnetic Ordering in Ultrasmall Potassium Ferrite Nanoparticles Grown on Graphene Nanoflakes

“…Antiferromagnetism and opening of a magnetic hysteresis at room temperature with a saturation moment of 0.58 μ B /Fe at 1.5 T were observed. This scarce interest in nanoscale downsizing of such compounds is all the more surprising given their utility in a variety of catalytic processes and as solid-state electrolytes. ,,,− …”

“…This scarce interest in nanoscale downsizing of such compounds is all the more surprising given their utility in a variety of catalytic processes and as solid-state electrolytes. 11,18,19,[23][24][25][26][27][28] Carbon templated magnetic nanoparticles [29][30][31] are sought after for biological applications such as magnetic and combined magneticphotonic hyperthermia treatment, 32 magnetic drug carriers, 33 or multimodal contrast agents for bioimaging, 34 ] and as negative contrast agents in magnetic resonance imaging (MRI). 35,36 Recently, some of us have reported the synthesis of 2-5 nm diameter iron oxide/hydroxide nanoparticles grafted to the framework of graphitic nano carbons (Fe(nP)/nC), 37,38 by exploiting the low reduction potential of graphenide solutions.…”

Preparation of NiFe2O4 Nanoparticles by Solution Combustion Method as Photocatalyst of Congo red

“…Photocatalytic degradation using ferrite compounds effectively reduces pollutant toxicity because the pollutants are degraded into smaller and harmless molecules such as H2O and CO2 [7]. The ferrite compound is a catalyst that has a stable structure, excellent magnetic properties, and low bandgap energy [10,11]. The separation of ferrite compounds from solutions can be completed without filtration by utilizing external magnets, making them efficient and promising in industrial applications [12].…”

Cationic Dye Degradation and Real Textile Wastewater Treatment by Heterogeneous Photo-Fenton, Using a Novel Natural Catalyst

“…Textile factories produce wastewater characterized by a very low biodegradability, high amounts of surfactants, high chemical oxygen demand (COD), toxicity, highly fluctuating temperature and pH, and a strong color [3,4]. These textile effluents represent a serious problem for the environment, and even their degradation products may be toxic, thus threatening public health and aquatic organisms [5].…”