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 LiNi0.33Mn0.33Co0.33O2 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.
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.
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.
To customize the traditional SrFeO3 (SFeO) cathode for proton-conducting solid oxide fuel cells (H-SOFCs), a Ta cation and F anion co-doping approach is suggested. It has been discovered that Ta-doping can enhance the oxygen vacancy content and the protons' and oxygen's diffusion capacities, enabling improved H-SOFC performance. Ta-doping alone, however, only modestly enhances the cathode's performance, which is still below that of many newly created cathodes. The F anion co-doping is further introduced to further improve performance, resulting in the formation of the SrFe0.9Ta0.1O2.9F0.1 (SFeTOF) cathode. When SFeTOF is compared to the single Ta-doping material, its proton and oxygen diffusion properties are further improved, demonstrating the efficacy of using Ta and F co-doping for SFeO. Consequently, the fuel cell utilizing the SFeTOF cathode for H-SOFCs displays a fuel cell output of 1559 mW cm−2 at 700 °C, notably higher than the fuel cell that uses SFeO or Ta-doped SFeO cathodes. The performance is likewise impressive among the H-SOFC cathodes that are now in use. Moreover, the fuel cell utilizing the SFeTOF cathode demonstrates sufficient operational stability in operating conditions, establishing SFeTOF as a reliable and effective cathode for H-SOFCs.
SiO, with a high theoretical specific capacity and acceptable volume variation, is considered one of the most promising next-generation anode materials. However, there is limited research on the effect of SiO particle size distribution on the electrochemical performance of LIBs. In this study, we investigated the impact of the ratio of submicron particles (0.1 μm to 1 μm) on the electrochemical performance. It found that a combination of micron and submicron particles with the ratio of submicron particles (RoS) in processed SiO at around 90 % resulted in optimal enhanced capacity and cycling stability, while the remaining 10 % of micron particles mitigate the side reactions caused by excessive surface area. This work is believed to provide a new perspective for inspiring long-span life SiO-based LIBs.
Globally, vast amount of food-derived waste is generated including residues from fruit processing, which requires innovative strategies to avoid problematic disposal of useful resources. Orange peels contain a variety of valuable compounds such as limonene, enzymes, and carbohydrates that exhibit interesting properties for various applications. In this work, a biorefinery concept is presented to generate versatile bioproducts from orange peel waste. First, limonene and peroxidase enzymes were extracted from orange peels by solvent extraction and three phase partitioning, respectively. The remaining solids, containing mainly cellulose, were enzymatically hydrolyzed, and soluble monosaccharides converted into lactic acid (LA) by Weizmannia coagulans and the biopolyester polyhydroxybutyrate (P(3HB)) by Priestia megaterium. 8 g L−1 limonene and peroxidases with remarkable specific activity of 426 U mg−1 were extracted. Utilization of the sugars in batch fermentations resulted in a LA concentration of 17 g L−1 as well as a P(3HB) content up to 43 % in cell dry weight without the need for further medium components. By combining these bioproducts, fully biobased polymer blend films of P(3HB) with PLA and limonene as plasticizer were successfully fabricated by thermoplastic processing, i.e., extrusion. In conclusion, the tested concept has shown very promising results and thereby emphasize the potential of the presented valorization strategies for orange peel waste.
Aqueous zinc-ion batteries (AZIBs) are gaining rising popularity as potential energy storage solutions for large-scale renewable energy, attributed to their affordable pricing and inherent safety features. The reversible capacity of AZIBs, which is crucial for their cycle performance, is significantly influenced by the choice of cathode material, with Na3V2(PO4)3 standing out as promising candidates for their large 3D transport channels and rapid kinetics. However, they suffer from rapid degradation caused by low structural stability during the charge-discharge process. In this work, we researched the electrochemical performance of cathode materials by employing a sol-gel preparation for Mn-doped Na3-xV2-xMnx(PO4)3/rGO (x = 0, 0.05, 0.1), in which graphene oxides (rGO) were introduced as carbon sources. It is identified that the Mn doping exerts a beneficial influence to enhance stability of the structure. The Mn0.05-NVP/rGO material, optimized for performance, exhibits a specific capacity of 106.3 mAh·g−1 with a discharge plateau at 1.3 V at a current density of 100 mA·g−1, which corresponds to an energy density of 134.7 Wh·kg−1. Particularly, the addition of Mn enhances cycling performance, leading to a remarkable capacity retention rate of 75.3 % even after 100 cycles. This work confirms the feasibility using NASICON-type cathodes and offers valuable perceptions into the advancement of cathode materials in AZIBs.
The traditional Fenton process has two issues that hinder its further application and promotion. One is the generation of large amounts of iron sludge. The other is the safe storage and transport of explosive H2O2. The problems could be solved by accelerating to regenerate Fe(II) and realizing to self-generate H2O2. The key to the solution lies in the use of reducing active hydrogen [H] to supply electrons. The effect of different loading methods of Pd0 nanoparticles (NPs), active centres for [H] generation, on the catalytic performance is unknown. Herein, the Pd/UiO-66(Zr) (Pd0 NPs loaded on the surface of UiO-66(Zr)) and Pd@UiO-66(Zr) (Pd0 NPs confined into the pores of UiO-66(Zr)) were synthesized. It confirmed that the [H] could be used to promote to regenerate Fe(II) and self-generate H2O2. Using only a trace amount of ferrous (25 μM) and without H2O2, the trimethoprim (20 mg·L−1) could be thoroughly removed within 90 min. Moreover, the stability of Pd@UiO-66(Zr) was slightly superior to that of Pd/UiO-66(Zr) because of the confinement effect of pore wall on Pd0 NPs, as well as the interception effect on the intermediate products that can be complexed with Pd0 NPs.