Institute of Fundamental Technological Research

Nwaji N., Juyong G., My‐Chi N., Huu‐Quang N., Hyojin K., Youngeun C., Youngmi K., Hongxia C., Jaebeom L., Emerging potentials of Fe-based nanomaterials for chiral sensing and imaging, Medicinal Research Review, ISSN: 1098-1128, DOI: 10.1002/med.22003, pp.Journal of Medicinal Research-22003, 2024

Abstract:
Fe-based nanostructures have possessed promising properties that make it suitable for chiral sensing and imaging applications owing to their ultra-small size, non-toxicity, biocompatibility, excellent photostability, tunable fluorescence, and water solubility. This review summarizes the recent research progress in the field of Fe-based nanostructures and places special emphases on their applications in chiral sensing and imaging. The synthetic strategies to prepare the targeted Fe-based structures were also introduced. The chiral sensing and imaging applications of the nanostructures are discussed in details.

Pietrzyk-Thel P., Jain A., Bochenek K., Michalska M., Basista M. A., Szabo T., Nagy P., Wolska A., Klepka M., Flexible, tough and high-performing ionogels for supercapacitor application, Journal of Materiomics, ISSN: 2352-8478, DOI: 10.1016/j.jmat.2024.01.008, pp.1-41, 2024

Abstract:
Ionogels are an attractive class of materials for smart and flexible electronics and are prepared from the combination of a polymer and ionic liquid which is entrapped in this matrix. Ionogels provide a continuous conductive phase with high thermal, mechanical, and chemical stability. However, because of the higher percentage of ionic liquids it is difficult to obtain an ionogel with high ionic conductivity and mechanical stability, which are very important from an application point of view. In this work, ionogel films with high flexibility, excellent ionic conductivity, and exceptional stability were prepared using polyvinyl alcohol as the host polymer matrix and 1-ethyl-3-methylimidazolium hydrogen sulfate as the ionic liquid using water as the solvent for energy storage application. The prepared ionogel films exhibited good mechanical stability along with sustaining strain of more than 100% at room temperature and low temperature, the ability to withstand twisting up to 360° and different bending conditions, and excellent ionic conductivity of 5.12 × 10−3 S/cm. The supercapacitor cell fabricated using the optimized ionogel film showed a capacitance of 39.9 F/g with an energy and power densities of 5.5 Wh/kg and 0.3 kW/kg, respectively confirming the suitability of ionogels for supercapacitor application.

Keywords:
Ionic liquid, Gel polymer electrolyte, Ionic conductivity, 1-Ethyl-3-methylimidazolium hydrogen sulfate, Supercapacitors

Witecka A., Pietrzyk-Thel P., Krajewski M., Sobczak K., Wolska A., Jain A., Preparation of activated carbon/iron oxide/chitosan electrodes for symmetric supercapacitor using electrophoretic deposition: A facile, fast and sustainable approach, JOURNAL OF ALLOYS AND COMPOUNDS, ISSN: 0925-8388, DOI: 10.1016/j.jallcom.2024.174040, Vol.985, No.174040, pp.1-15, 2024

Abstract:
In this research, electrophoretic deposition (EPD) was employed to prepare a porous composite film (ACF electrode) consisting of 90 wt% activated carbon particles, 10 wt% iron oxide nanoparticles, and a chitosan as binder in a facile, fast, and sustainable manner. This micro-mesoporous composite film, with a thickness of ∼45 µm and a surface area of ∼208.1 m2g−1, was coated on a stainless steel substrate. The SEM and TEM investigations proved the homogeneous distribution of carbon microparticles and iron oxide nanoparticles in the deposit, while the EDX, XRD, Raman spectroscopy, and XPS confirmed the chemical composition. ACF electrodes were also used in a symmetric two-electrode cell configuration with a sandwiched gel polymer electrolyte - PVdF(HFP)-PC-Mg(ClO4)2 and revealed a specific capacitance of ∼54.4 F g−1, along with satisfactory energy and power density of ∼4.7 Wh kg−1 and 1.2 kW kg−1, respectively, and excellent electrochemical stability up to ∼10,000 cycles (with merely 8.5% decay by the 5000th cycle). Obtained results confirmed the stability of the used system and its possible application in the field of energy storage and conversion.

Nwaji N., Getasew Mulualem Z., Juyong G., Hyojin K., Lemma Tushome T., Yujin C., Mahedra G., Hyeyoung S., Jaebeom L., Dimeric NiCo single-atom anchored on ultrathin N-doped 2D molybdenum carbide boosted performance in solid-state supercapacitor, Journal of Energy Storage, ISSN: 2352-152X, DOI: 10.1016/j.est.2024.110671, Vol.83, pp.Journal of Energy Storage-110671, 2024

Abstract:
Tuning the electronic structure of single-atom catalysts through dimeric single-atom formation could be an innovative approach to increasing their energy storage activity, but the process of achieving this is challenging. In this study, we designed a simple technique to obtain Nisingle bondCo single atom dimers (SADs) anchored on N-doped molybdenum carbide (N-Mo2C) through in-situ encapsulation of Nisingle bondCo into molybdenum polydopamine, followed by annealing with optimal tuning of nitrogen dopant. The Nisingle bondCo atomic level coordination was confirmed with X-ray absorption spectroscopy. When used as energy storage supercapacitor, The NiCo-SADs showed enhanced specific capacity (1004.8 F g−1 at 1 A g−1), enhanced rate capability (75 %), and exceptional cycling stability (93.6 % with 98.5 % coulombic efficiency) via a dominant capacitive charge storage. The augmented charge storage characteristics are attributed to the collaborative features of the active Nisingle bondCo constituents acting as electron reservoir for effective adsorption of HO− ion during the electrochemical process. The DFT study showed thermodynamically favorable OH− adsorption between the three metal bridges that promoted redox reaction kinetics and enhanced conductivity for the NiCo-SADs. When using N-Mo2C as the anode to fabricate hybrid supercapacitors, the device exhibits high energy density of 69.69 Wh kg−1 at power density of 8200 W kg−1, respectively and shows excellent long-term cycling stability (93.42 % after 3000 cycles), which affirms the potential of the assembled device for applications in solid state supercapacitors.

Zhang Y., Nwaji N.^♦, Wu L., Jin m., Zhou G., Giersig M., Wang X., Qiu T., Akinoglu E.M., MAPbBr3/Bi2WO6 Z-scheme-Heterojunction Photocatalysts for photocatalytic CO2 reduction, JOURNAL OF MATERIALS SCIENCE, ISSN: 0022-2461, DOI: 10.1007/s10853-023-09220-w, Vol.59, pp.Journal of Material Science-1498-1512, 2024

Abstract:
Photocatalytic CO2 reduction has emerged as a promising strategy for converting solar energy into valuable chemicals, capturing the attention of scientists across various disciplines. Organic and inorganic perovskites, particularly methylammonium lead bromide (MAPbBr3), have demonstrated potential in this field due to their remarkable visible-light response and carrier transport properties. However, the catalytic performance of pristine MAPbBr3 has been limited by severe charge recombination, hindering its applicability in photocatalytic systems. Here, we show that a MAPbBr3/Bi2WO6 (MA/BWO) heterojunction significantly enhances photocatalytic CO2 reduction performance compared to individual pristine MA or BWO. This enhancement is evidenced by the superior performance of the 25% MA/BWO composite, which exhibits CO and CH4 release rates of 1.82 μmol/g/h and 0.08 μmol/g/h, respectively. This improvement is attributed to the direct Z-scheme heterojunction formed between MAPbBr3 and Bi2WO6, which facilitates efficient charge separation and suppresses charge recombination. The results challenge the previous understanding of MAPbBr3-based photocatalysts and demonstrate a novel approach for developing highly active organic and inorganic perovskite photocatalysts. The successful application of the MA/BWO heterojunction in photocatalytic CO2 reduction expands the scope of organic and inorganic perovskites in the field of renewable energy conversion. By providing a broader perspective, our findings contribute to the ongoing efforts towards sustainable energy solutions, appealing

Refilwe M., Nwaji N., Muthumuni M., Zhi-Long C., Tebello N., Photodynamic therapy characteristics of phthalocyanines in the presence of boron doped detonation nanodiamonds: Effect of symmetry and charge, Phothodygnosis, ISSN: 1873-1597, DOI: 10.1016/j.pdpdt.2021.102705, Vol.37, pp.Photodygnosis and photodynamic therapy-102705, 2024

Abstract:
he synthesis, photophysicochemical and photodynamic therapy (PDT) activities of benzothiazole substituted zinc phthalocyanine (Pc): 1 (asymmetrically substituted and composed of no charges), 2 (asymmetrically substituted and composed of three positive charges), and 3 (symmetrically substituted and composed of four positive charges), are presented. The triplet and singlet oxygen quantum yields were highest for complex 2 showing the importance of asymmetry and charge. The complexes are covalently and non-covalently linked to B doped detonation nanodiamonds (B@DNDs) to yield nanohybrids (B@DNDs-1, B@DNDs-2, B@DNDs-3). The presence of B@DNDs, asymmetry and positive charge resulted in improved PDT with the lowest cell viability being observed for B@DNDs-2 at 5%. The cell viability ranged from 5% to 7% for the nanohybrids compared to 19–26% for Pcs alone.

Osial M., Ha G., Vu V., Nguyen P., Nieciecka D., Pietrzyk‑Thel P., Urbanek O., Olusegun S., Wilczewski S.^♦, Giersig M., Do H., Dinh T., One-pot synthesis of magnetic hydroxyapatite (SPION/HAp) for 5-fluorouracil delivery and magnetic hyperthermia, Journal of Nanoparticle Research, ISSN: 1388-0764, DOI: 10.1007/s11051-023-05916-x, Vol.26, No.7, pp.1-23, 2024

Abstract:
This work presents the synthesis and characterization of a composite made of superparamagnetic iron oxide and hydroxyapatite nanoparticles (SPION/HAp) with a well-developed surface for loading anticancer drugs and for use in magnetic hyperthermia and local chemotherapy. The proposed material was obtained by an easy one-pot co-precipitation method with a controlled ratio of SPION to HAp. The morphology was studied by SEM and TEM, indicating rod-like structures for high HAp content in the composite and granule-like structures with increasing SPION. Its crystallinity, elemental composition, and functional groups were determined by X-ray diffraction, EDS, and FT-IR, respectively. The nanocomposite was then stabilized with citrates (CA), polyethylene glycol (PEG), and folic acid (FA) as agents to improve intracellular absorption, while turbidimetric studies confirmed that only citrates effectively stabilized the magnetic carriers to form a colloidal suspension. Subsequently, 5-fluorouracil (5-FU) was loaded into the magnetic carriers and tested in vitro using the L-929 cell line. The studies showed no cytotoxicity of the citrate-stabilized suspension against fibroblasts and some cytotoxicity after 5-FU release. In addition to in vitro studies, the composite was also tested on biomimetic membranes made of DOPC, DOPE, cholesterol, and DOPS lipids using Langmuir trough. The results show that the resulting suspension interacts with biomimetic membranes, while magnetic hyperthermia studies confirm effective heat generation to achieve therapeutic 42–46 °C and improve drug release from magnetic carriers.

Keywords:
SPION, Hydroxyapatite, Magnetic hyperthermia, Drug delivery, 5-fluorouracil, Biomimetic membranes, Nanostructures, Cancer treatment

Grigoryan N., Chudziński P., Role of electron-electron interactions in electron emission from nanotube materials, PHYSICAL REVIEW MATERIALS, ISSN: 2475-9953, DOI: 10.1103/PhysRevMaterials.8.016003, Vol.8, pp.1-16, 2024

Abstract:
Nanotubes and nanorods have been recently established as very good materials to work as electron sources in a field emission (FE) process. These are one-dimensional materials and electron-electron interactions are expected to play a crucial role in their physics. Here we study the influence of electron-electron interactions on the field emission. We study the problem in the low energy regime; thus we need to abandon the antiadiabatic approximation and derive tunneling amplitude for a finite duration of the tunneling process. In this work we identified the parameters when exact analytic expression for tunneling current can be given. We obtained formalism that enables one to capture at the same time the collective effects due to electron-electron interactions and thermionic emission. Our results reveal that different types of nanotubes, and their minigap/compressibility parameters, can be easily distinguished based on FE measurements on these materials.

Olusegun S., Souza Guilhermina de O., Sutuła S., Osial M., Krajewski M.^♦, Pękała M., Sobczak K., Felis E., Krysiński P., Methotrexate anti-cancer drug removal using Gd-doped Fe3O4: Adsorption mechanism, thermal desorption and reusability, Groundwater for Sustainable Development, ISSN: 2352-801X, DOI: 10.1016/j.gsd.2024.101103, Vol.25, pp.1-9, 2024

Keywords:
Adsorption,Thermal desorption,Gd-doped Fe3O4,Methotrexate

Pulov V., Kowalczuk W., Mladenov I.M., Geometry of Enumerable Class of Surfaces Associated with Mylar Balloons, Mathematics, ISSN: 2227-7390, DOI: 10.3390/math12040557, Vol.12, No.4, pp.557-1-18, 2024

Abstract:
In this paper, the very fundamental geometrical characteristics of the Mylar balloon like the profile curve, height, volume, arclength, surface area, crimping factor, etc. are recognized as geometrical moments ℐ

Keywords:
Mylar balloons, geometrical moments, elliptic integrals, beta and gamma functions, recursive relations, crimping factor, lemniscate constant