Guillermina Leticia Luque

Al ₂ W ₃ O ₁₂ belongs to the A ₂ M ₃ O ₁₂ family of ceramics, which is known for its unique mechanical and thermal properties. Due to its low positive thermal expansion, this phase is a good candidate for applications that require high resistance to thermal shock. In addition, a strong interest in this ceramic family has recently emerged due to its low-density structure with a lot of empty spaces capable of storing alkaline ions. Therefore, these orthorhombic open-framework structures can be potentially useful as electrodes in lithium-ion batteries (LIBs). Here, Al ₂ W ₃ O ₁₂ was synthesized by co-precipitation method and subsequently used as active material in LIBs, achieving a discharge capacity of 130 mA h g ⁻¹ at the 100 ^th cycle. Two post-synthesis routes were applied to add carbon phases to Al ₂ W ₃ O ₁₂ , providing an additional mechanism to tune the energy delivered by LIB using Al ₂ W ₃ O ₁₂ as the active material. The first route considered mechanical mixing of the as-obtained ceramic powder with graphite, achieving a discharge capacity of 292 mA h g ⁻¹ at the 100 ^th cycle. In the second approach, sucrose impregnation followed by a dehydration step within a strong acid medium was used as a carbon source, and the discharge capacity of this material was 220 mA h g ⁻¹ at the 100 ^th cycle. Complete electrochemical performance of all three materials was studied and compared. This study shows that the addition of carbon to Al ₂ W ₃ O ₁₂ is a promising approach to enhance charge storage capacity and electrochemical performance of open-framework A ₂ M ₃ O ₁₂ -based phases.

A few members of the flexible open‐framework A ₂ M ₃ O ₁₂ ceramics, sometimes deliberately containing oxygen vacancies (OVs), have been investigated for photocatalytic applications and for uses requiring high thermal shock resistance, owing to their negative or near‐zero thermal expansion. In some other relevant crystal structures, OVs have been reported to enhance charge storage capacity, rate performance, and Li ⁺ diffusion in lithium‐ion batteries (LIBs). In this study, the electrochemical properties of Al ₂ W ₃ O ₁₂ ‐based electrodes with and without OVs have been compared when used as anode materials for LIBs. Extrinsic OVs were introduced into Al ₂ W ₃ O ₁₂ , which served as the active material by the treatment in a hydrogen atmosphere, and their presence was confirmed by electron paramagnetic resonance. Despite these modifications, the OV‐containing electrode delivered a discharge capacity of 110 mAh g ⁻¹ at the 100 ^th cycle, which was lower than that of the electrode without OVs (133 mAh g ⁻¹ at the same cycle). Contrary to the expectations based on previous studies of other relevant LIB electrode materials, Al ₂ W ₃ O ₁₂ with OVs exhibited inferior electrochemical performance. Structural and morphological analyses revealed rapid amorphization of the extremely flexible open‐framework structure in OV‐rich Al ₂ W ₃ O ₁₂ during the initial lithiation cycles, which likely accounts for the absence of a beneficial effect of OVs on the specific capacity.

The thermal processing of walnut shells was investigated through pyrolysis within the range of 100–650 °C, highlighting the influence of thermal engineering parameters on biomass conversion. The resulting biochar was subjected to chemical activation with phosphoric acid, and its physicochemical properties were evaluated to determine how thermal processing enhances its performance as a cathode material for lithium–sulfur (Li–S) batteries. This approach underscores the role of thermal engineering in bridging biomass valorization with energy storage technologies. In parallel, the gaseous fraction generated during walnut shell fast pyrolysis was collected, and for the first time, volatile organic compounds (VOCs) under atmospheric conditions were identified using solid-phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC–MS). The composition of the VOCs was characterized, quantifying aromatic compounds, hydrocarbons, furans, and oxygenated species. This study further linked the thermal decomposition pathways of these compounds to their atmospheric implications by estimating tropospheric lifetimes and evaluating their potential contributions to air quality degradation at the local, regional, and global scales.

Lithium‐oxygen batteries have gained prominence in recent years due to their potential advantages over conventional lithium‐ion batteries, including higher energy density, cost‐effectiveness and environmental sustainability. To fully exploit these advantages, it is essential to understand the interplay between porous carbon electrode materials and electrolytes in these devices. This study presents a nuclear magnetic resonance investigation of the confined LiTFSI (lithium bis(trifluoromethanesulfonyl)imide) ‐ TEGDME (tetraethylene glycol dimethyl ether) electrolyte within carbonaceous materials with different pore sizes. Three carbon materials (microporous, mesoporous, and hierarchical) were synthesized from the same precursor to ensure equivalent surface chemistry, which was verified by X‐ray photoelectron spectroscopy. The dynamics and distribution of solvent and Li ions in the different pores were studied by H and Li, 1D and 2D exchange, NMR spectroscopy. It was found that the accessibility of Li within the pores of the carbonaceous material depends not only on their size but also on their size distribution. The knowledge gained from this study can contribute to the design of the appropriate pore size distribution, which could optimize the electrolyte utilization and consequently increase the energy density of lithium‐oxygen batteries.

Lithium–sulfur (Li-S) batteries are promising candidates for next-generation energy storage due to their high energy density, cost-effectiveness, and environmental friendliness. However, their commercialization is hindered by challenges, such as the polysulfide shuttle effect, lithium dendrite growth, and low electrical conductivity of sulfur cathodes. Cellulose, a natural, renewable, and versatile biopolymer, has emerged as a multifunctional material to address these issues. In anode protection, cellulose-based composites and coatings mitigate dendrite formation and improve lithium-ion diffusion, extending cycle life and enhancing safety. As separators, cellulose materials exhibit high ionic conductivity, thermal stability, and excellent wettability, effectively suppressing the polysulfide shuttle effect and maintaining electrolyte stability. For the cathode, cellulose-derived carbon frameworks and binders improve sulfur loading, conductivity, and active material retention, resulting in higher energy density and cycling stability. This review highlights the diverse roles of cellulose in Li-S batteries, emphasizing its potential to enable sustainable and high-performance energy storage. The integration of cellulose into Li-S systems not only enhances electrochemical performance but also aligns with the goals of green energy technologies. Further advancements in cellulose processing and functionalization could pave the way for its broader application in next-generation battery systems.

This comprehensive review explores anode-free post-Li metal batteries (Na, K, Mg, Zn, Al), emphasizing metal-philicity, current collector functionalization strategies, insights from computational studies, and advancements in electrolyte formulations.