MoS2 QDs-nanoparticle-engineered based hydrophobic filter for high performance water-oil separation

Design of hydrophobic polyurethane-magnetite iron oxide-titanium dioxide nanocomposites for oil-water separation

Efficacious oil-water separation has become a global challenge owing to regular oil spillage accidents and escalating industrial oily wastewater. In this study, we synthesized titanium dioxide and magnetite iron oxide nanoparticles to use as a precursor for the production of the nanocomposites. Hydrophobic nanocomposites were fabricated using polyurethane, hematite and magnetite iron oxide nanoparticles, and titanium dioxide nanoparticles through a sol-gel process. The formation of the obtained nanocomposites was confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) analyses. In addition, the thermogravimetric and differential thermogravimetric (TGA/DTG) and BET surface area results exhibited enhanced thermal stability of the optimized nanocomposite which displayed mesoporous type materials feature with high porosity. Furthermore, the obtained outcomes demonstrated that the distribution of nanoparticles into a polymer matrix had a significant impact on enhancing superhydrophobicity and the separation efficiency against sunflower oil. Seeing the water contact angle of the nanocomposite-coated filter paper was about 157° compared to 0° for the uncoated filter paper and endowed separation efficiency of almost 90% for 5 consecutive cycles. Thereby, these nanocomposites could be an ideal candidate for self-cleaning surfaces and oil-polluted water purification.

MoS2 Nanosheets Decorated with Fe3O4 Nanoparticles for Highly Efficient Solar Steam Generation and Water Treatment

The shortage of water resources has always been one of the most difficult problems that perplexes humanity. Solar steam generation (SSG) has been a new non-polluting and low-cost water purification method in recent years. However, the high cost of traditional photothermal conversion materials and the low efficiency of photothermal conversion has restricted the large-scale application of SSG technology. In this work, composite materials with Fe3O4 nanospheres attached to MoS2 nanosheets were synthesized, which increased the absorbance and specific surface area of the composite materials, reduced the sunlight reflection, and increased the photothermal conversion efficiency. During the experiment, the composite material was evenly coated on cotton. The strong water absorption of cotton ensured that the water could be transported sufficiently to the surface for evaporation. Under one sun irradiation intensity, the evaporation rate of the sample synthesized in this work reached 1.42 kg m-2 h-1; the evaporation efficiency is 89.18%. In addition, the surface temperature of the sample can reach 41.6 °C, which has far exceeded most photothermal conversion materials. Furthermore, the use of this composite material as an SSG device for seawater desalination and sewage purification can remove more than 98% of salt ions in seawater, and the removal rate of heavy metal ions in sewage is close to 100%, with a good seawater desalination capacity and sewage purification capacity. This work provides a new idea for the application of composite materials in the field of seawater desalination and sewage purification.

New insights into MXene applications for sustainable environmental remediation

Multiple ecological contaminants in gaseous, liquid, and solid forms are vented into ecosystems due to the huge growth of industrialization, which is today at the forefront of worldwide attention. High-efficiency removal of these environmental pollutants is a must because of the potential harm to public health and biodiversity. The alarming concern has led to the synthesis of improved nanomaterials for removing pollutants. A path to innovative methods for identifying and preventing several obnoxious, hazardous contaminants from entering the environment is grabbing attention. Various applications in diverse industries are seen as a potential directions for researchers. MXene is a new, excellent, and advanced material that has received greater importance related to the environmental application. Due to its unique physicochemical and mechanical properties, high specific surface area, physiological compatibility, strong electrodynamics, and raised specific surface area wettability, its applications are growing. This review paper examines the most recent methods and trends for environmental pollutant removal using advanced 2D Mxene materials. In addition, the history and the development of MXene synthesis were elaborated. Furthermore, an extreme summary of various environmental pollutants removal has been discussed, and the future challenges along with their future perspectives have been illustrated.

The efficient and green synthesis of biodiesel from crude oil without degumming catalyzed by sodium carbonate supported MoS2

The transesterification of lecithin with methanol catalyzed by 23 kinds of alkaline salts was investigated for the preparation of biodiesel. Sodium carbonate was confirmed as the best catalyst due to its excellent catalytic performance, environmental friendliness, and great stability. Next, it was successfully immobilized on the surface of hierarchical nanosheets of MoS₂. The prepared catalyst was characterized via XRD, FTIR, SEM, and TEM techniques. After immobilization, the highest specific activity reached 40.58 ± 0.78 U mg_Na2CO3⁻¹, which was 2.43 times higher than that of unsupported Na₂CO₃. Meanwhile, the highest yield reached 99.8%. The excellent performance of the supported catalysts was attributed to a synergistic effect between MoS₂ and the absorbed sodium carbonate. Firstly, sodium carbonate was uniformly dispersed on the surface of MoS₂ to minimize the mass transfer resistance. Secondly, the electron-rich outer layer of MoS₂ promoted the deprotonation of methanol to form methoxy anions. The prepared catalyst was further applied in the transesterification of lecithin-containing triglycerides to prepare fatty acid methyl esters (FAMEs). The experimental results showed that the addition of lecithin would promote the transesterification of triglycerides. The yields of FAMEs were close to 100% in all cases when the lecithin content was increased from 1% to 40%. Hence, this supported sodium carbonate catalyst should be a promising candidate for biodiesel production from crude oil without degumming.

The transesterification of lecithin with methanol catalyzed by sodium carbonate supported MoS₂ was investigated for the preparation of biodiesel.