Energie-Materialien

With rising demand for lithium-ion batteries, efficient recycling is crucial. While conventional methods face cost and environmental challenges, electrochemical recovery offers a sustainable and energy-efficient alternative. In this study, we investigate the electrochemical recovery of lithium-ions from spent lithium iron phosphate batteries using carbon-coated lithium iron phosphate electrodes, with a focus on the influence of pH adjustment and competing ion effects. Our results demonstrate that NaOH-adjusted electrolytes provide the highest lithium-ion recovery efficiency, with an average removal capacity of 18 mgLi gLFP−1 over 50 cycles. However, prolonged cycling leads to capacity fading, particularly in the presence of competing cations such as Na+ and K+, which impact lithium selectivity and electrode stability. These findings underscore the importance of optimizing electrolyte conditions and electrode materials to enhance long-term performance. Future research should explore alternative pH control strategies and scalable process designs to facilitate industrial implementation. Advancing electrochemical lithium-ion recovery aligns with broader sustainability goals, offering a viable route toward circular battery recycling and reduced environmental impact.

Lithium–sulfur batteries (Li–S), controlled by the sulfur cathode’s conversion reaction, are a promising technology due to their high theoretical capacities and the sustainability of sulfur. In contrast to commercially available lithium-ion cathodes, the Li–S system still suffers from unstable cycling performance due to the diffusion of soluble polysulfides out of the cathode. This study explored sulfur cathodes with varying pore sizes, mainly in the micropore regime (<2 nm). We conducted the work using carbonate-based and ether-based electrolytes to investigate the impact of the cathode/solid electrolyte interphase on the cycling performance of the battery. By infiltrating the carbon with different C/S ratios, we found that the maximum sulfur infiltration attained was 61 mass % with a C/S ratio of 1:1.5. The best sulfur utilization and cycling performance were achieved with carbonate electrolyte and 50 mass % S in carbon with a specific surface area of 2210 m2/g and a total pore volume of 1.20 cm3/g. Our findings emphasize the importance of designing cathodes with optimized pore structures to balance sulfur accommodation, minimize sulfur dissolution, and mitigate capacity degradation.

We report the successful synthesis of nanocomposites between the MXene Ti3C2Tx and polyaniline (PAni), achieved via an innovative approach starting from the intercalation of anilinium ions into non-exfoliated Ti3C2Tx, and followed by a liquid/liquid interfacial polymerization. This approach produces transparent films with beneficial optical quality. The spectroscopic analysis confirmed the formation of PAni in its conductive form, emeraldine salt. The absence of TiO2 bands in the Raman spectra indicated that the organic polymer protected Ti3C2Tx from degradation, even in acidic media. Electrochemical characterization revealed that the nanocomposites exhibited promising performance as supercapacitors, with specific capacity dependent on the amount of polymer. The combination of the conductive Ti3C2Tx and the redox activity of PAni, as well as the specific nanoarchitecture in which the materials are organized, significantly improved the electrochemical response, facilitating ion diffusion. These transparent films demonstrated specific capacity values up to 89 mAh g-1 at 0.1 mAh g-1, with the potential for further enhancement through current collector optimization, positioning them as strong candidates for miniaturized energy storage applications and transparent devices.

The synthesis of an amphiphilic three-arm block copolymer (AB)3-BCP, which consists of poly(methyl methacrylate) (PMMA) and poly(butyl methacrylate) (PBMA) in the hydrophobic inner block, is reported. The hydrophilic block segment is based on poly(2-hydroxyethyl methacrylate) (PHEMA) originating from 2-(trimethylsiloxyl)ethyl methacrylate (HEMA-TMS). The preparation is carried out in two steps using a core-first approach. Using atom transfer radical polymerization (ATRP) as a controlled polymerization technique, three (AB)3-BPCs with HEMA contents of 15 to 38 mol−1 % are prepared, applying different reaction conditions. Porous structures are generated from these BCPs by applying a self-assembly and nonsolvent-induced phase separation (SNIPS) protocol. Complex surface structures are observed using scanning electron microscopy (SEM). Bulk morphologies are investigated for a better understanding of the underlying self-assembly. For PHEMA-rich (AB)3-BCPs, non-regular lamellar microphases are observed in transmission electron microscopy (TEM) and confirmed by small-angle X-ray scattering (SAXS). The porous structures and their expected swelling characteristics are analyzed using atomic force microscopy (AFM) in air and water. Time-resolved measurements in water indicate a rapid swelling after immersion into the water bath. The present study paves the way for exciting porous materials based on the herein synthesized amphiphilic three-arm block copolymers useful for applications as absorber materials and coatings.

The demand for lithium production has seen a significant rise, with the growing electric vehicle and stationary battery markets requiring further development of sustainable and scalable extraction methods. Direct lithium extraction technologies have been developed to address potential shortages, with adsorption emerging as a key method due to its efficiency and low environmental impact. Given that Al(OH)3 is already utilized as an adsorbent in various industrial applications, the practical importance of Al-based alternative systems for lithium ion extraction is increasing, yet lithium ion recovery requires harsh chemicals. In this study, we report a novel lithium extraction method combining chemical adsorption and electrochemical release using a synthesized aluminum layered double hydroxide (Al-LDH) material, developed under mild reaction conditions. The performance of the Al-LDH electrode was evaluated against a commercial Al(OH)3 adsorbent. Comprehensive characterization using techniques such as X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy revealed detailed insights into the crystalline structure, particle size distribution, and surface morphology of the materials. The Al-LDH electrode exhibited a lithium ion adsorption capacity, achieving an average chemical uptake of lithium ions of 57.6 mg/g. In contrast, lithium-ion uptake capacity for Al(OH)3 was 1.0 mg/g over 15 cycles. Notably, this method operates under pH-neutral conditions, eliminating the need for harsh acidic or basic eluents. As a result, it prevents structural degradation and minimizes secondary pollution for potential future applications of lithium-ion recovery. The material’s layered structure selectively allowed lithium ion intake while blocking sodium ions, demonstrating its high selectivity and utility in lithium ion recovery processes. The integration of pH-neutral regeneration and high selectivity shows that Al-LDH electrodes as viable candidates for next-generation, green lithium extraction technologies.

This work presents a novel approach to enhance the specific energy of supercapacitors by developing Bi2O3/Mn3O4/Mn2AlO4(OV)/rGO multiphase oxygen vacancy heterostructures via dealloying and hydrothermal self-growth strategy. The synergy between reduced graphene oxide (rGO) heterostructures and oxygen vacancy defects generates an internal polarized electric field that accelerates ion transport and enhances electrochemical response through an interconnected conductive network. This innovation extends the operating voltage from 0.6 to 0.8 V, significantly improving material energy storage. An asymmetric supercapacitor assembled with Bi2O3/Mn3O4/Mn2AlO4(OV)/rGO//rGO delivers a specific energy of 333 Wh kg−1 and a specific power of 6.3 kW kg−1 at a cell voltage of 4.9 V. At the highest specific power (31 kW kg−1), the specific energy remains at 204 Wh kg−1. Density functional theory (DFT) simulations further validate that the synergy of oxygen vacancies and heterostructures enhances conductivity, narrows the bandgap, and improves surface properties, unveiling novel theoretical perspectives on ion transport dynamics within oxygen vacancy heterostructures.

This study presents a novel approach to developing high-performance lithium-ion battery electrodes by loading titania-carbon hybrid spherogels with sulfur. The resulting hybrid materials combine high charge storage capacity, electrical conductivity, and core-shell morphology, enabling the development of next-generation battery electrodes. We obtained homogeneous carbon spheres caging crystalline titania particles and sulfur using a template-assisted sol-gel route and carefully treated the titania-loaded carbon spherogels with hydrogen sulfide. The carbon shells maintain their microporous hollow sphere morphology, allowing for efficient sulfur deposition while protecting the titania crystals. By adjusting the sulfur impregnation of the carbon sphere and varying the titania loading, we achieved excellent lithium storage properties by successfully cycling encapsulated sulfur in the sphere while benefiting from the lithiation of titania particles. Without adding a conductive component, the optimized material provided after 150 cycles at a specific current of 250 mA g–1 a specific capacity of 825 mAh g–1 with a Coulombic efficiency of 98%.

The growing demand for lithium batteries in various applications has increased lithium production from multiple sources, including ores, brines, and spent batteries. Traditional extraction methods such as mining and evaporation ponds have significant environmental risks, such as air pollution and loss of habitats for aquatic and terrestrial animals. Furthermore, they cannot meet the ever-increasing demand for lithium in the global market. Consequently, industries have been exploring rapid and sustainable lithium recovery methods from these sources. Similar to what shale did for oil industry, Direct Lithium Extraction (DLE) represents a promising approach poised to enhance lithium production efficiency. This method not only reduces operation time but also brings added sustainability benefits. Various DLE methods have been proposed, such as adsorption, ion exchange, membranes, direct carbonation, and electrochemical processes. This paper comprehensively analyzes DLE technologies, including their fundamentals, principles, and applications. The focus is on various techniques used in DLE, highlighting their respective strengths and limitations. The study explores the potential of DLE for efficient and sustainable lithium recovery, considering the growing demand for lithium in the energy sector. Furthermore, the analysis examines the challenges associated with DLE, including cost, environmental impact, and scalability. This paper contributes to a greater understanding of the opportunities and limitations of DLE to inspire future crucial research efforts in this strategically important emerging technology.

Capacitive deionization (CDI) has emerged as a promising desalination technology and recently promoted the development of multichannel membrane capacitive deionization (MC-MCDI). In MC-MCDI, the independent control of multiflow channels, including the feed and electrolyte channels, enables the optimization of electrode operation in various modes, such as concentration gradients and reverse voltage discharge, facilitating semicontinuous operation. Moreover, the integration of redox couples into MC-MCDI has led to advancements in redox-mediated desalination. Specifically, the introduction of redox-active species helps enhance the ion removal efficiency and reduce energy consumption during desalination. This systematic approach, combining principles from CDI and electrodialysis, results in more sustainable and efficient desalination. These advancements have contributed to improved desalination performance and practical feasibility, rendering MC-MCDI an increasingly attractive option for addressing water scarcity challenges. Despite the considerable interest in and potential of this process, there is currently no comprehensive review available that covers the operational features and applications of MC-MCDI. Therefore, this Review provides an overview of recent research progress, focusing on the unique cell configuration, vital operation principles, and potential advantages over conventional CDI. Additionally, innovative applications of MC-MCDI are discussed. The Review concludes with insights into future research directions, potential opportunities in industrial desalination technology, and the fundamental and practical challenges for successful implementation.

A suitable interface between the electrode and electrolyte is crucial in achieving highly stable electrochemical performance for Li-ion batteries, as facile ionic transport is required. Intriguing research and development have recently been conducted to form a stable interface between the electrode and electrolyte. Therefore, it is essential to investigate emerging knowledge and contextualize it. The nanoengineering of the electrode-electrolyte interface has been actively researched at the electrode/electrolyte and interphase levels. This review presents and summarizes some recent advances aimed at nanoengineering approaches to build a more stable electrode-electrolyte interface and assess the impact of each approach adopted. Furthermore, future perspectives on the feasibility and practicality of each approach will also be reviewed in detail. Finally, this review aids in projecting a more sustainable research pathway for a nanoengineered interphase design between electrode and electrolyte, which is pivotal for high-performance, thermally stable Li-ion batteries.