The results of carbon dioxide reforming of CH₄ (model biogas) on catalysts prepared by solution combustion synthesis (SCS) and impregnation of moisture capacity methods are presented. Investigation of the activity of catalysts synthesized from initial mixtures of Co(NO₃)₂-Al(NO₃)₃-urea of different compositions was carried out for the production of synthesis-gas, and SCS and traditional incipient wetness impregnation catalyst preparation methods were compared. The methane conversion reached 100%, and the conversion of CO₂ increased to 86.2%, while the yield of H₂ and CO was 99.2% and 85.4%, respectively, at 900 °C. It was found that CoAl₂O₄ spinel formation was due to substitution of Al³⁺ with Co²⁺ cations. Consequently, CoAl₂O₄ lattice parameters increased, since the ionic radius of Al³⁺ (0.51 Å) less than Cο²⁺ (0.72 Å). Advantages of SCS catalysts in comparison with catalysts prepared by the traditional incipient wetness impregnation method in dry reforming of methane were shown. The aim of this work is to develop a new catalyst for the conversion of model biogas into synthesis gas, which will contribute to the organization of a new environmentally friendly, energy-saving production in the future.

Additive manufacturing, also known as 3D printing or digital fabrication technology, is emerging as a fast-expanding technology for the fabrication of prototypes and products in a variety of applications. This is mainly due to the advantages of 3D printing including the ease of manufacturing, the use of reduced material quantities minimizing material waste, low-cost mass production as well as energy efficiency. Polylactic acid (PLA) is a natural thermoplastic polyester that is produced from renewable resources and is routinely used to produce 3D-printed structures. One important feature that makes PLA appealing is that its properties can be modulated by the inclusion of nano or microfillers. This is of special importance for 3D-printed triboelectric nanogenerators since it can enhance the performance of the devices. In this work we investigate the influence of SiC micron-sized particles on the mechanical, electrical, and optical properties of a PLA-SiC composite for potential application in triboelectric energy harvesting. Our result show that the ultimate tensile strength of the pure PLA and 1%-doped PLA decreases with the number of fatigue cycles but increases by about 10% when SiC doping increases to 2% and 3%, while the strain at max load was about 3% independent of doping and the effective hardness was increased reaching a plateau at about 2 wt% SiC, about 40% above the value for pure PLA. Our results show that the mechanical properties of PLA can be enhanced by the inclusion of SiC, depending on the concentration of SiC. In addition, the same behavior is observed for the dielectric constant of the composite material increases as the SiC concentration increases, while the optical properties of the resulting composite are strongly dependent on the concentration of SiC.

The worldwide increase in demand for environmentally friendly energy has led to the intensification of work on the synthesis of H₂-containing fuel. The dry reforming of methane has become one of the most important avenues of research since the consumption of two greenhouse gases reduces the rate of global warming. A study of NiAl composite materials as catalysts for methane reforming has been carried out. Self-propagating high-temperature synthesis (SHS) has been used to produce NiAl catalysts. Comparative studies were carried out regarding the dry reforming and partial oxidation of methane, as well as catalysts prepared using the impregnation (IM) and SHS methods. A catalyst with 29% Ni and 51% Al after SHS contains the phases of NiAl and NiAl₂O₄, which are active phases in the dry reforming of methane. The optimal crystal lattice parameter (for the maximum possible conversion of CO₂ and CH₄) is 3.48–3.485 Å for Al₂O₃, which plays the role of a catalyst carrier, and 1.42 Å, for NiAl₂O₄, which plays the role of a catalyst. The aim of the work is to develop a new and efficient catalyst for the dry reforming of methane into a synthesis gas, which will further promote the organization of a new era of environmentally friendly energy-saving production methods.

The morphology and surface characteristics of SCS (Solution Combustion Synthesis)-derived Ni–NiO nanocatalysts were studied. The ΤΕΜ results highlighted that the nanomaterial’s microstructure was modified by changing the reactants’ concentrations. The dendrites’ growth conditions were the main factors responsible for the observed changes in the nanomaterials’ crystallite size. Infrared camera measurements demonstrated a new type of combustion through dendrites. The XPS analysis revealed that the NiO structure resulted in the bridging of the oxygen structure that acted as an inhibitor of hydrogen adsorption on the catalytic surface and, consequently, the activity reduction. The RF-IGC indicated three different kinds of active sites with different energies of adsorption on the fresh catalyst and only one type on the aged catalyst. Aging of the nanomaterial was associated with changes in the microstructure of its surface by a gradual change in the chemical composition of the active centers.