Sustainable Materials and Technologies最新文献

Efficient and cost-effective recycling of spent lithium-ion batteries is essential for the sustainable growth of the clean energy sector, conserves critical mineral resources, and contribute to environmental sustainability. The pyrometallurgy process, involving high-temperature smelting and solid-state reduction, plays a key role in the industrial-scale recycling of these batteries. Traditional smelting methods, however, face criticism for their substantial energy requirements and the loss of lithium in slag. In this study, an innovative laser-based in-situ pyrometallurgical process, hereinafter referred to as laser recycling, was developed to recycle Li-ion batterie materials without using slag, enabling the simultaneous recovery of Co, Ni, Mn, and Li. Lab-scale experiments were carried out to investigate the influences of laser power density and duration on the carbothermic reduction behavior of battery materials. The results showed that the maximum temperature reached approximately 1850 °C with a laser power between 1500 and 2000 W focused to an area of 20 mm in diameter within a few seconds. The laser recycling facilitates concurrent smelting and solid-state reduction, with carbothermic reduction completed in just 30 s due to rapid reaction kinetics, ultra-high temperatures, and the enhanced contact area resulting from surface tension-driven molten material flow under intense laser beam exposure. This laser recycling process reduced LiCoO₂ and LiNi_0.33Mn_0.33Co_0.33O₂ to metallic Co or Co-Ni-Mn alloy, respectively, while Li was recovered as Li₂CO₃. The new process allowed for the near-total recovery of Co, Ni, and Mn in the alloy and virtually 100% Li recovery in the form of Li₂CO₃ by a vapor phase capture system. Additionally, continuous laser recycling in the battery material powder bed showed potentials to scale up for industry battery recycling. A mechanism for the laser recycling process was proposed. A preliminary discussion on the techno-economic implications of laser recycling was also provided.

Sustainable technologies and the circular economy paradigms require a reduction of waste, and therefore, research is focusing on the development of sustainable materials and devices capable of being reused, refurbished or recycled.

In the present work, printable ionic liquid (IL)-based polymer composites with thermochromic properties have been developed through a more sustainable approach to mitigate the negative impact of advanced functional materials and processes. For this purpose, composite films based on a natural polymer, cellulose acetate (CA), and different contents of the thermochromic IL, bis(1-butyl-3-methylimidazolium) tetrachloronickelate ([Bmim]₂[NiCl₄]), have been processed by a solvent casting method for the development of sustainable temperature sensors. The composites are transparent at room temperature, but when exposed to a temperature of 50 °C, the colour changes to blue. Incorporating the thermochromic IL led to the appearance of pores in the material's structure, which increased with increasing IL concentration. Additionally, the Young Modulus decreases with increasing IL concentration, reaching a value of 840 ± 158 MPa) for the sample with 40 % wt. Contrarily, the electrical conductivity strongly increases with the highest DC electrical conductivity, with a maximum conductivity of 1.1 × 10–5 ± 1.5 × 10–6 S.cm-1 obtained for the sample with 40 % wt. of [Bmim]₂[NiCl₄].

As a proof of concept, the potential applicability of the developed natural-based nanoparticle-free materials was demonstrated with a CA/40[Bmim]₂[NiCl₄] sample by the development of printable thermochromic temperature sensors for thermotherapy applications in the temperature range from 33 °C to 50 °C.

This paper investigates the performance of hybrid composites made from mixed waste plastics (wMP), recycled carbon fibre (rCF), and waste glass fibre (wGF). Two lay-up configurations with varying wGF and rCF contents were considered: one with approximately 7 vol% rCF (25 vol% wGF) and another with approximately 15 vol% rCF (9.4 vol% wGF). The tensile, compressive, and flexural performance of standard coupon specimens for both configurations were assessed, revealing that specimens with increased rCF content exhibited superior performance. Additionally, three hybrid C-sections, containing 15 vol% rCF, were thermoformed and subjected to axial compression. All three C-sections failed due to bearing failure, accompanied by some interlaminar delamination and material crushing at the loading ends. Their weight-specific load capacity surpassed that of similar sections published in the literature, such as ultra-thin-walled steel C-sections, by almost 95 %. A finite element model (FEM) of the C-section was developed and was able to predict reasonably well the stress versus strain response. These findings demonstrate that waste and recycled composite materials could serve as sustainable alternatives to ultra-thin-walled steel C-sections and other conventional materials commonly used in construction.