Single-phase multicomponent perovskite-type cobalt oxide containing five cations in equiatomic amounts on A-site, namely (Gd0.2Nd0.2La0.2Sm0.2Y0.2)CoO3, has been synthesized via modified co-precipitation hydrothermal method. Using an original approach for heat treatment, which comprises quenching utilizing liquid nitrogen as a cooling medium, a single-phase ceramic with high configuration entropy, crystallizing in orthorhombic distorted structure was obtained. It reveals anomalous temperature dependence of the lattice expansion with two weak transitions at approx. 80 K and 240 K that are assigned to gradual crossover from low, via intermediate to high spin state of Co3+. The compound exhibits weak ferromagnetism at T  10 K, and signatures of antiferromagnetic correlations in the paramagnetic phase. Ab initio calculations predict a band gap  = 1.18 eV in the ground state electronic structure with the dominant contribution of O_p and Co_d orbitals in the valence and conduction bands, respectively. Electronic transport measurements confirm the negative temperature coefficient of resistivity characteristic to semiconducting material and reveal a sudden drop of activation energy at T ~ 240 K from Ea ~ 1 eV in low-temperature phase to Ea ~ 0.3 eV at room temperature. The possibility of fine-tuning of the semiconducting band gap via a subtle change in A-site stoichiometry is discussed.

According to the International Energy Agency, biorefinery is “the sustainable processing of biomass into a spectrum of marketable bio-based products (chemicals, materials) and bioenergy (fuels, power, heat)”. In this review, we survey how the biorefinery approach can be applied to highly porous and nanostructured materials, namely aerogels. Historically, aerogels were first developed using inorganic matter. Subsequently, synthetic polymers were also employed. At the beginning of the 21st century, new aerogels were created based on biomass. Which sources of biomass can be used to make aerogels and how? This review answers these questions, paying special attention to bio-aerogels’ environmental and biomedical applications. The article is a result of fruitful exchanges in the frame of the European project COST Action “CA 18125 AERoGELS: Advanced Engineering and Research of aeroGels for Environment and Life Sciences”.

The article presents the results of research on thermal decomposition of Ester-Cured Alkaline Phenolic No-Bake (ALPHASET) binders used in molding technology. In the ALPHASET system phenol-formaldehyde resin of resole type is cured with a liquid mixture of esters. Under the influence of the molten metal the thermal decomposition of the binder follows, resulting in the evolution of gases, often harmful, e.g. from benzene, toluene, ethylbenzene and xylenes (BTEX) or Polycyclic Aromatic Hydrocarbon (PAH) groups. The identification of gases evolved during the pyrolysis of the binders was carried out and their decomposition temperatures were determined using the Thermogravimetry–Gas Chromatography–Mass Spectrometry (TG–GC–MS) technique. The tests were subjected to two types of binders from different manufacturers. Among the products of pyrolysis there have been identified mainly benzene and its derivatives, and phenol and its derivatives. Compounds identified in pyrolytic gas are largely considered to be harmful to humans and the environment (some of the compounds are carcinogenic and mutagenic). The presented results of the TG–GC–MS measurements show that the applied analytic methods are feasible to perform a qualitative and also quantitative characterization of the binder samples

Zinc ferrite ZnFe₂O₄ both in the micro and nano scale is widely used in various fields. The article discusses the structure of this compound and its properties in the nanoscale, which is clearly different from those which the ferrite shows in the microscale. The properties of dust generated electric arc furnace, which can contain up to 40% zinc, substantially in the form of ZnFe₂O₄ are disscused here. Specific properties (electric, magnetic, thermal) of zinc ferrite nanoparticles determine the very wide possibilities of their use, inter alia as catalysts, absorbents, gas sensors, and a tool to combat cancer.

Superparamagnetic iron oxide nanoparticles doped with zinc and modified with a cationic derivative of chitosan (SPION-Zn-CCh(+)) that exhibited enhanced activity in magnetic hyperthermia were synthesized and characterized structurally, magnetically, and biologically. The optimum zinc content and the polymer coating were found to be important to maximize the hyperthermic effect in the obtained nanoferrites, which effectively worked at concentrations as low as 0.55 mg Fe per mL. The average core diameter was found to be ca. 10 nm as revealed by SAXS and TEM measurements, while the formed small aggregates of the polymer coated nanoparticles reached a size of ca. 200 nm. The nanoferrite structure was further obtained using Mössbauer spectroscopy and XANES revealing the maximum Zn doping. The much higher (ca. 60%) intrinsic loss power determined for SPION-Zn-CCh(+) as compared to the native iron oxide nanoparticles, together with the long term (12 months) stability of their dispersion and biocompatibility, makes these nanoferrites very promising materials for magnetic hyperthermia therapy. The proposed synthetic method employing a cationic polysaccharide opens up also new opportunities for the formation of other metal ferrites with composition and structure previously unobtainable and potentially superior e.g. magnetic properties.

Cancer is among the leading causes of death worldwide, thus there is a constant demand for new solutions, which may increase the effectiveness of anti-cancer therapies. We have designed and successfully obtained a novel, bifunctional, hybrid system composed of colloidally stabilized superparamagnetic iron oxide nanoparticles (SPION) and curcumin containing water-soluble conjugate with potential application in anticancer hyperthermia and as nanocarriers of curcumin. The obtained nanoparticulate system was thoroughly studied in respect to the size, morphology, surface charge, magnetic properties as well as some biological functions. The results revealed that the obtained nanoparticles, ca. 50 nm in diameter, were the agglomerates of primary particles with the magnetic, iron oxide cores of ca. 13 nm, separated by a thin layer of the applied cationic derivative of chitosan. These agglomerates were further coated with a thin layer of the sodium alginate conjugate of curcumin and the presence of both polymers was confirmed using thermogravimetry. The system was also proven to be applicable in magnetic hyperthermia induced by the oscillating magnetic field. A high specific absorption rate (SAR) of 280 [W/g] was registered. The nanoparticles were shown to be effectively uptaken by model cells. They were found also to be nontoxic in the therapeutically relevant concentration in in vitro studies. The obtained results indicate the high application potential of the new hybrid system in combination of magnetic hyperthermia with delivery of curcumin active agent.