Materials Technology Reports

A ubiquitous waste as a superior adsorbent for methylene blue removal: Cow-hair biochar

2025-02-14T06:02:37+00:00

The efficient and sustainable removal of organic dyes from wastewater remains a critical environmental challenge. In this study, cow hair, an abundant and underutilized agricultural waste, is transformed into biochar through a simple pyrolysis process to develop an effective and eco-friendly adsorbent for methylene blue (MB) dye removal. The physicochemical properties of the cow-hair biochar, including its surface area, porosity, and functional groups, were systematically analyzed to understand its adsorption performance. Batch adsorption experiments were conducted under varying conditions of pH, initial dye concentration, contact time, and pH to evaluate the adsorption efficiency of cow hair biochar. The results revealed that the biochar exhibits superior adsorption capacity for MB, driven by a combination of electrostatic interactions, π-π stacking, and surface oxygen functional group interactions. Using R² as criteria, the best-fitting model was the Temkin isotherm, indicating a monolayer adsorption process with a maximum adsorption capacity surpassing many conventional adsorbents, achieving high levels of MB adsorption capacity of 730 mg/g. This study highlights the potential of converting cow hair waste into a high-performance adsorbent, offering a cost-effective and sustainable solution for dye-contaminated wastewater treatment. The findings pave the way for innovative waste valorization strategies and contribute to the advancement of green environmental technologies.

3D-printed poly (lactic acid) scaffolds coated with cationic macro-biocide: Investigation of anti-biofilm activity and thermo-mechanical properties

2025-03-03T08:09:17+00:00

In this study, the primary goal was to combine surface modification and 3D printing technology to create materials with anti-biofilm action. In order to achieve this, first a two-step reaction procedure using ring-opening copolymerization and copper(I)-catalyzed azide-alkyne cycloaddition click reaction was used to successfully fabricate poly (lactic acid) (PLA) bearing quaternary ammonium salt (QAS) as an antimicrobial agent on its backbone at rates of 5% by mole. Then, this synthesized PLA-based (co)polymer dissolved in acetone with a weight percentage of 30% was used to coat 3D-printed PLA by dipping for 10, 30, and 90 s. These coated samples encoded PLA/10/PLA-QAS, PLA/30/PLA-QAS, and PLA/90/PLA-QAS, respectively. The coated PLA scaffolds were then characterized by Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria were used to assess the anti-biofilm activity of the samples. In addition, the thermal and mechanical properties of the samples were examined through differential scanning calorimetry (DSC) and three-point bending tests, respectively. Consequently, covering the 3D-printed PLA surfaces with synthesized antimicrobial polymer prevented the formation of biofilms against both bacteria, and all coated samples showed no toxicity in 25% and 10% extraction mediums. And, it was observed that the antimicrobial polymer solution had a plasticizing effect on the PLA scaffold. As the dipping times increased, the glass transition temperatures of the coated samples decreased. In terms of flexural behaviors, increasing the dipping time also improved the flexural strain of coated PLA scaffolds. These thermo-mechanical results are correlated with SEM morphologies because of the penetration and solution effect of antimicrobial polymer dissolved in acetone.

A study of the underlying dynamics of phase-space projection of microwave-assisted synthesis of transition metal nanostructures

2025-01-02T08:49:16+00:00

The study brings together in a single publication the phase-space projection analysis of microwave-assisted synthesis of transition monometallic (palladium, silver, platinum, and gold), binary zinc oxide, and metals supported on carbon framework nanostructures. It is shown for a database of fifty microwave-assisted syntheses, a two-variable power-law signature (y = cxn) over four orders of magnitude. The purpose of this study is therefore to identify the underlying dynamics of the power-law signature. A dual allometry test is used to discriminate between transition metal period and row, and between recommended Green Chemistry, problematic Green Chemistry, and non-Green Chemistry hazardous solvents. Typically, recommended Green Chemistry exhibits a broad y-axis distribution within an upper exponent = 1 and lower exponent = 0.5. Problematic Green Chemistry exhibits a y-axes narrower distribution with an upper exponent = 0.94 and a lower exponent = 0.64. Non-Green Chemistry hazardous data shows a further narrowing of the y-axis distribution within upper exponent = 0.87 and lower exponent = 0.66. Mass-based environmental factor is used to calculate the ‘Greenness’ of single-step (facile) transition metal synthesis. The power-law signature also exhibits phase transitions associated with microwave applicator type.

Preparation of nascent disentangled ultra-high molecular weight polyethylene based on Ziegler-Natta catalyst

2025-01-17T01:16:14+00:00

Ziegler-Natta (Z-N) catalysts hold great significance in the industrial production of ultrahigh molecular weight polyethylene (UHMWPE), given that their outstanding efficacy, profound impact on the molecular weight (MW) of UHMWPE, and extensive industrial applications are highly conspicuous. However, the UHMWPE prepared by Z-N catalyst is usually highly entangled. Considering chain entanglement is essential for altering the processability and mechanical characteristics of nascent UHMWPE, the synthesis of disentangled UHMWPE (dis-UHMWPE) is essential for industrial scalability, therefore holding considerable practical importance. This review summarized recent progress in optimizing Z-N catalysts for the synthesis of dis-UHMWPE, providing a comprehensive overview of research advancements, clarifying polymerization settings, linking polymer structure and activity, and introducing design principles for polymerization techniques. Moreover, the overarching objective is to reveal the principles behind material preparation methods and potentiate the application prospects of UHMWPE materials, therein propelling the advancement of related fields.

Graphene—A hello and goodbye

2025-01-21T02:39:48+00:00

After years of research, it can be stated that graphene was an initial game changer and jack of all trades in the world of nanotechnology, owing to innumerable structural/physical characteristics and mammoth range of hi-tech applications. Undoubtedly, since the discovery of graphene, it almost ruled all possible nanotechnological fields, from electronics/energy—to—defense/transportation/civil—to—biomedical. Nevertheless, this statement remained no longer valid after the discovery of more erudite nanostructures, like fullerene, quantum dots, and similar nanoparticles. Reasons for today’s technology turns towards tiny symmetrical nanoparticles seem to be the limitations/hinderance for integrating graphene into energy/semiconducting/photonic devices, and subsequent commercialization over past two decades. In this novel perspective report, therefore, we first time critically analyzed the nanotechnological shifts from graphene, yet despite its early promises, towards proficient zero dimensional entities.