The present paper analyses the properties of printed polylactic acid (PLA) samples with admixtures of graphene nanopowder (GNP) at wt. 1%, 2% and 4%. The pure polylactide and admixed polylactide printed samples were examined to determine their chemical-physical properties, stiffness, and strength parameters. The tests of tensile, dynamic mechanical analysis (DMA), difference thermogravimetric (TG), and differential scanning calorimetry (DSC) were executed before and after UV (ultraviolet) treatment. The first part of the paper shows the process of manufacturing granulates and filaments mixed with graphene. The second part of the paper concerns the results of the tests made on printed samples. The analysed samples were printed using a Prusa i3 MK3 printer. It transpired that the content of graphene at 1% improved the mechanical parameters of the printed composite by organising its structure. Increasing the amount of graphene caused the values of the measured parameters to drop. This research indicates how important it is to determine the optimal values of nanoadditives in biopolymers.

This study aims to present various forms of cellulose, whose shape depends on the source of origin, and to demonstrate the differences in the influence on the properties of materials produced with its participation. For this purpose, composites with various plant additives have been designed and obtained. Some of them have undergone chemical and pyrolytic modifications. The results of the mechanical, physicochemical and microscopic tests showed differences in cellulose structure, even in the case of very similar sources, and its diversified influence on the characteristics of the obtained materials. The research shows the effect of the use of natural additives and their modified versions on the mechanical properties of the composite based on epoxy resin. It turns out that cellulose modifiers are not only fillers that reduce the price of the final product but can also increase some mechanical properties, e.g., compressive strength, which is an additional advantage and a reason for wider use. The potential of natural resources is not yet fully understood. Relatively recently, people have started to be interested in cellulose on a nanometric scale, as it turns out that it can exist in several different forms with interesting properties.

Continuous growth in energy demand is observed throughout the world, with simultaneous rapid consumption of fossil fuels. New effective technologies and systems are needed that allow for a significant increase in the use of renewable energy sources, such as the sun, wind, biomass, and sea tides. Currently, one of the main research challenges refers to thermal energy management, taking into account the discontinuity and intermittency of both energy supply and demand. Phase change materials (PCMs) are a useful solution in the design and manufacturing of multifunctional materials for energy storage technologies such as solar cells and photovoltaic systems. In order to design efficient PCM-based systems for energy applications, ideas and behaviors from nature should be taken account as it has created over millions of years a plethora of unique structures and morphologies in complex hierarchical materials. Inspirations for nature have been applied to improve and adjust the properties of materials for energy conversion and storage as well as in the design of advanced energy systems. Therefore, this review presents recent developments in biomimetic and bio-inspired multifunctional phase change materials for the energy storage and conversion of different types of renewable energy to thermal or electrical energy. Future outlooks are also provided to initiate integrated interdisciplinary bio-inspired efforts in the field of modern sustainable PCM technologies.

Green energy conversion and storage materials have become a focal point of research in recent times, especially in energy-consuming buildings. Phase change materials (PCMs) have gained more and more attention not only for energy storage but also in composites for solar energy conversion. This research investigates a sustainable method for converting orange biomass waste (OBW) into advanced porous carbon aerogel (PCA) composites, designed for solar-thermal energy harvesting and storage in building applications. Using potato starch as a binder, the research develops a process for producing a uniform and lightweight carbon matrix that could be scalable. The best results were found for PCA obtained with 2.5% starch, where the lowest mass loss (8.2, 0.5, 11.2% pt) was observed during the leakage test. This study highlights the suitability of OBW-derived aerogels as effective matrices for PCM impregnation and shape stabilization, indicating their future potential in solar-thermal energy conversion and storage and potentially lowering energy consumption in buildings. By repurposing agricultural waste, this work contributes to sustainable material development and advances the application of renewable energy technologies.

In recent years, there has been an increasing interest in phase change materials (PCM) based on dulcitol and other sugar alcohols. These materials have almost twice as large latent heat of fusion as other organic materials. Sugar alcohols are relatively cheap, and they can undergo cold crystallization, which is crucial for long-term thermal energy storage. The disadvantage of dulcitol and other sugar alcohols is the solid–liquid phase transition. As a result, the state of matter of the material and its volume change, and in the case of materials modified with microparticles or nanoparticles, sedimentation of additives in liquid PCM can occur. In this study, we obtained shape-stable phase change materials (SSPCM) by co-gelation of starch and dulcitol. To characterize the samples obtained, differential scanning calorimetry (DSC), step-mode DSC, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were used, and they were also used to test for shape stabilization. The results show that the obtained systems have great potential as shape-stabilized phase change materials. The sample dulcitol/starch with a 50:50 ratio exhibited the highest heat of cold crystallization, up to 52.90 J/g, while the heat of melting was 126.16 J/g under typical DSC measuring conditions. However, depending on the applied heating program, the heat of cold crystallization can even reach 125 J/g. The thermal stability of all compositions was higher than the phase change temperature, with only 1% mass loss occurring at temperatures above 200 °C, while the phase change occurred at a maximum of 190 °C.

Organic phase change materials (PCMs) have been used and studied for many years. In this work, we focus on an industrially available PCM—polyethylene waxes (PEW) modified with seven types of carbon black (CB) exhibiting different properties. Carbon black (CB) was selected as a more cost-effective modifier compared to carbon nanomaterials, as it is easier to implement industrially and capable of converting and storing thermal energy. The experiments were designed to evaluate the thermal properties and photothermal conversion efficiency of PCMs modified with different grades of carbon black. The influence of carbon black on selected PCM properties was investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TG), scanning electron microscopy (SEM), and laser flash analysis (LFA). Furthermore, the photothermal conversion capability was evaluated. The results indicate that modification with carbon black decreases the phase transition enthalpy for most formulations, with reductions ranging from 8 to 12% for 1 wt.% CB to 10–15% for 2.5 wt.% CB. At the same time, an improvement in the thermal conductivity of PCMs modified with carbon black was observed, with the best performance achieved for N234 carbon black, showing an increase of approximately 17–18% in the 25–55 °C temperature range. The ratio of the heat of solidification to the heat of melting (Qs/Qm) for most samples was approximately 0.90–0.98, indicating excellent thermal cycling stability. The highest photothermal conversion efficiency was observed for samples modified with N234 and N330; these materials exhibited the greatest temperature rise, reaching approximately 135 °C in about 15 min, due to enhanced light absorption of PCMs by carbon black. Overall, the results confirm that PEW/CB systems demonstrate a good balance between absorption, heat generation, and controlled phase-change behavior, making them promising candidates for solar–thermal energy storage and conversion applications.