ABSTRACT The electrocatalytic ethanol oxidation reaction is bottlenecked by inefficient C─C bond cleavage. This challenge is epitomized at metal‐oxide heterointerfaces, where the active site identity and cleavage mechanism remain obscured. Here, we decoded this by atomically programming model PdO─Pt 3 Pd heterointerfaces. Through 18 O isotopic labeling, we identify the interfacial lattice oxygen (O Int ) in Pd 2+ ─O Int ─Pd alloy motif as the direct oxygen donor for C─C cleavage. The interfacial built‐in electric field activates O Int as a nucleophilic scalpel by upshifting its p‐band center, resulting in an ultralow cleavage barrier of 0.47 eV. Beyond a single site, we demonstrate that the interface functions as a reaction‐network architect. It creates a dominant O Int ‐mediated “non‐CO” C1 pathway at the PdO─Pt 3 Pd heterointerface while re‐engineering the traditional “CO” pathway on the adjacent Pt 3 Pd domain via threefold optimization: minimizing *CO source, suppressing acetate formation and ensuring rapid *CO removal. This dual‐path integration yields breakthrough performance with a mass activity of 9.09 A mg metal −1 and a C1‐pathway Faradaic efficiency of 75.6%. This work reports a paradigm shift from a passive “scavenger” model to an active “initial‐attack and system‐orchestration” mechanism, redefining heterointerfaces as atomically programmable reaction‐network architects. This paradigm offers a blueprint for mastering complex reaction networks, extending the frontier of rational catalyst design.

The scarcity of protons in alkaline media limits many proton-coupled energy conversion processes, particularly the hydrogen evolution reaction (HER). Here, we introduce a strategy to create a confined acidic microenvironment within strongly alkaline solution. Ultramicroporous Brønsted acidic zeolites stabilize hydrated protons through a size-exclusion effect, in the presence of bulky quaternary ammonium bases. In situ diffuse reflectance infrared Fourier transform spectroscopy and first-principles simulations reveal that confined protons derived from Brønsted acid sites migrate into the hydrogen-bond network of water, forming a Zundel-Eigen continuum that supports Grotthuss transport. Complementary inelastic neutron scattering and solid-state nuclear magnetic resonance confirm the persistence of hydrated protons under highly alkaline conditions. Guided by this principle, we developed a composite catalyst combining proton-donating nanoparticles with active, conductive layers, which delivers a 19-25% reduction in overpotential, a 20-fold enhancement in Pt mass activity, and accelerated kinetics compared with commercial Pt/C. These findings establish a broadly applicable framework for decoupling local proton activity from bulk pH, opening new pathways for HER and other proton-coupled reactions in alkaline environments.

Experimental reproducibility in electrochemistry is fundamentally limited by process uncertainty. This challenge, especially pronounced in complex systems like Fe-based multi-metal electrodeposition, is a major bottleneck for high-throughput and autonomous materials discovery. To address this, we present a generalizable curve aggregation framework that combines Gaussian Process Regression (GPR) with Functional Data Analysis (FDA) to aggregate replicate measurements while preserving within-curve correlation structure. The method represents each transient as a continuous function and iteratively optimizes curve-wise weights to emphasize consistent signals and suppress outliers. We validate the framework using potentiostatic transients from near-equiatomic CoCuFeNi electrodeposition across seven deposition conditions. The framework successfully aggregated 226 transients, quantified experimental variance and transient shape, and showed performance comparable to a more computationally intensive but physically robust first-principle measurement model. We find that uncertainty, bias, and convergence difficulty evolve with dataset size resembling a Dunning–Kruger-like pattern, where small datasets appear deceptively certain, followed by a maximum convergence difficulty peak, then converge to a stable final aggregate. For this system, the variance stabilized at approximately 𝑁 ≈ 35–40 measurements, providing a practical criterion for data sufficiency. The GPR-FDA framework is broadly applicable to any experimental field involving replicate functional data that must be aggregated without losing correlation information.

Porous liquids (PLs) represent a unique platform for molecular separations by combining permanent porosity with liquid-phase mobility. However, it remains a formidable challenge to construct and stabilize PLs with sub-5 Å pores using readily available porous host and liquid media. Here, we report the construction of cyclodextrin (CD)-derived PLs enabled by in situ solvation shell formation. The acid-base neutralization reaction between CD and an organic base was leveraged to generate a thin ionic solvation shell around the CD host, effectively liquefying CD and preventing its segregation in the liquid base medium while preserving accessible molecular-scale cavities. Spectroscopic analysis, neutron scattering, density functional theory calculations, and molecular dynamics simulations collectively confirm the structural evolution and existence of abundant internal porosity in PLs. The unique architectures of CD-derived PLs enable highly selective encapsulation of fluorinated alkanes and significantly enhanced uptake of inert gases. This facile and generalizable strategy enables construction of high-quality PLs with engineered ultramicroporosity to facilitate molecular separations.

Mixing anions is emerging as a promising strategy for multivalent electrolyte design, allowing for adjustment of the solvation structure of bulk cations and enhancing the efficiency of electrochemical processes (e.g. metal deposition for batteries and catalysis). Further progress in electrolyte development requires a fundamental understanding of how tailored electrolyte speciation in mixed anion systems can modify the dynamic electrochemical interface during metal cycling. In this study, we present an anode-focused mechanistic study of exemplar Mg electrolytes containing three different secondary anions, correlating electrochemical behavior with bulk speciation and operando interfacial dynamics. Electrospray Ionization-Mass Spectrometry (ESI-MS) results reveal a general trend of forming mixed anion contact ion pairs (CIPs) across various anions, with the extent of ion pairing influenced by the association strength of the secondary anion. Operando multiharmonic electrochemical quartz crystal microbalance with dissipation (EQCM-D) reveals how these bulk species influence interfacial mass uptake, viscoelasticity, and solvent-coupled hydrodynamic behavior during deposition and stripping. The results indicate that Mg-containing ion pairs and solvated complexes shape adsorption, nucleation, and deposit growth, leading to distinct anion-dependent interphases ranging from more permeable, solvent-coupled layers to relatively compact and rigid deposits. This work establishes a quantitative link between bulk speciation and interfacial dynamics in divalent metal electrodeposition and provides mechanistic guidance for electrolyte design.

High-entropy oxides (HEOs), as a subclass of high-entropy materials (HEMs), offer a versatile platform for catalysis by leveraging entropy-stabilized solid solutions with tunable compositions, lattice structures, and electronic properties. While exsolution-dissolution of metal species in crystalline HEOs has emerged as a promising strategy for reversible active sites regeneration, the dynamic behaviour of HEOs possessing amorphous nature remains under-explored, particularly the difference with crystalline counterparts. In this work, we systematically investigate the architecture-dependent exsolution-dissolution behavior of HEOs by comparing a crystalline-phase HEO (c-HEO) and an amorphous-phase HEO (a-HEO), both comprising Ni, Mg, Cu, Zn, and Co as principal metal elements. Using a combination of in situ variable-temperature X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electron microscopy, and in situ CO diffuse reflectance infrared Fourier transform spectroscopy (CO-DRIFTS), the structural evolution of the two HEO phases under redox conditions was elucidated. Both materials exhibit reversible exsolution of metallic species or alloys in reducing environments, followed by re-incorporation into the host lattice upon oxidation. Remarkably, the a-HEO demonstrates more facile and dynamic self-healing behavior, with alloy exsolution and dissolution occurring under milder conditions because of its enhanced reducibility and structural disorder. This study provides critical insights into the design of next-generation regenerable catalysts based on amorphous HEOs, highlighting the role of phase structure in governing reversible metal-site formation dynamics and catalytic performance.

In carbon engineering, a longstanding trade-off persists: chemical activation increases surface area but sacrifices conductivity, whereas graphitization enhances conductivity at the expense of porosity. In 2017, we introduced an electrochemical graphitization strategy using cathodic polarization in CaCl2-NaCl molten salts to convert hard carbon into graphite. Here, we reveal that this graphitization process initiates at the surface and propagates inward, enabling the transformation of mesoporous hard carbon into surface-graphitized mesoporous carbon. Meanwhile, this phenomenon is an electrochemical activation process: short-term graphitization rearranges carbon atoms to increase surface area from 397 to 867 m2/g, without significant mass loss. Unlike chemical activation, which achieves similar surface area gains at the cost of >50% yield loss, our method maintains nearly 100% carbon yield while preserving mesoporosity. The resulting material delivers a 17-fold increase in electrical conductivity (26-450 S/cm). This scalable, energy-efficient approach resolves the long-standing graphitization-porosity dilemma, producing carbons with both high conductivity and large accessible surface area.

Autonomous discovery is a growing concept in scientific research guided by data methods with minimal human input. The self-driving laboratory (SDL) is a key piece of the picture where robotics and/or fluidics are used to expedite screening while artificial intelligence (AI) and machine learning (ML) downselect the desired experiments. Electrochemical energy storage is a unique problem for automation as many electrochemistry workflows must be air-free. In our previous work, 1 we screened for oxidatively stable electrolyte solvents using an air-free robotic assay in a glovebox, resulting in over 6,000 spectroscopic kinetic experiments. Using AI/ML guidance, we found only a handful of solvents from a chemical space of 500 molecules met desirable stability metrics. While we initially developed these molecules for redox flow batteries, their oxidative stability is also highly pertinent for “beyond-lithium” sodium-ion batteries (NIBs). Sodium, with projected lower costs and high natural abundance, is proposed as a replacement for lithium-ion batteries (LIBs). However, NIBs are not a direct drop-in LIB replacement, and the NIB vs LIB electrolytes cannot be treated equally. 2 The higher Na/Na + potential necessitates higher cathode potentials to retain voltage, which causes faster oxidation of organic solvents. 3 Concomitant issues include gassing and electrode component dissolution. Therefore, developing solvents with greater oxidative stability, reduced gassing, and solubility tunability are essential for improving NIB performance. Here, we use chemistry and electrolyte-specific large language models and cheminformatics for new NIB electrolytes. AI-guided combinations are tested at our air-free platform at Argonne’s self-driving laboratory, RAPID (Robotic Autonomous Platforms for Innovative Discovery). Our approach is generalizable and includes automated electrochemical testing, analytical testing, and post-reactivity analyses. of the workflows. Our workflow will create a cradle to grave design and analysis of new electrolytes with artificial intelligence decision tree workflows for both experimental steps and data analysis. This material is based upon work supported by Laboratory Directed Research and Development (LDRD) funding from Argonne National Laboratory, provided by the Director, Office of Science, of the U.S. Department of Energy under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government. 1. Robertson et al., High-Throughput Discovery Illuminates Design Principles and Limits for Long-Lived Charged Species in Organic Electrolytes. J. Am. Chem. Soc. 2025 , 147 , 37211. 2. Song et al., Electrolyte chemistry development for sodium-based batteries: A blueprint from lithium or a step toward originality? Angew. Chem., Int. Ed. 2025 , 64 , e202424543; Monti et al. Towards standard electrolytes for sodium-ion batteries: physical properties, ion solvation and ion-pairing in alkyl carbonate solvents. Phys. Chem. Chem. Phys. 2020 , 22 , 22768. 3. Song and Kendrick, Recent progress on strategies to improve the high-voltage stability of layered-oxide cathode materials for sodium-ion batteries. J. Phys. Mater. 2021 , 4 , 032004.

Hydrogel-based sensing materials, known for their excellent flexibility and efficient signal transduction capabilities, have attracted significant attention in flexible electronics. However, the limited compression strength and single functionality of conventional strain-sensing hydrogels severely restrict their broader application. Herein, we report the development of a multifunctional nanocomposite pressure-sensing hydrogel featuring self-adhesion and antibacterial activity, synthesized via a two-step polymerization process. The polypyrrole (PPy) nanoparticles are first grown on melamine foam (MF) via oxidative polymerization to form MF@PPy. Subsequently, a polydopamine (PDA)-polyacrylamide (PAM) network is then polymerized within the porous MF@PPy structure to obtain the MF@PPy/PDA-PAM hydrogel. Compared to the pure PDA-PAM hydrogel, the compressive strain is significantly enhanced from 36% to 64%, owing to the resilient MF@PPy skeleton. Additionally, the incorporation of the adhesive PDA-PAM network endows the nanocomposite hydrogel with robust and repeatable adhesion to various substrates including steel, wood, paper, plastic, rubber, and glass with a maximum adhesion strength of 36.8 kPa. Furthermore, the nanocomposite hydrogel exhibits outstanding antibacterial performance, achieving bacterial survival rates of 1% against Escherichia coli (E. coli) and 8% against Staphylococcus aureus (S. aureus). Last but not least, it also shows an ionic conductivity of 12 mS cm-1 and a highly sensitive response at low pressures (0.3 kPa). This work presents a pressure-sensitive hydrogel sensor that integrates self-adhesion and antibacterial activity for real-time monitoring of human physiological activities, offering valuable insights for the development of multifunctional soft sensors.

Upcycling is recognized as a sustainable recycling approach for spent lithium-ion batteries. However, existing upcycling methods typically involve intricate pretreatment or post-treatment steps, complicating their practical application. Here, we propose a straightforward, etching-assisted upcycling method that effectively transforms polycrystalline Ni-lean cathodes into high-performance single crystal Ni-rich cathodes. During the etching step, nickel acetate was dissolved into acetic acid and then polycrystalline NMC111 are etched in the solution. Finally, polycrystalline NMC111 are converted into single crystal particles coated with amorphous nickel acetate. This significantly enhances elemental diffusion during subsequent sintering by minimizing both particle size and the contact distance between NMC111 and nickel acetate. As elemental diffusion is improved and acetate ions decompose completely during sintering, the process requires neither additional pretreatment nor post-treatment. The resulting cathode materials (Etched-UP622) exhibit superior structural and electrochemical properties compared to the Control622, achieving an energy density of 719.7 Wh/kg, approximately 56.7 mAh/g higher than Control622 and 125.5 Wh/kg higher than NMC111. Etched-UP622 also delivers higher discharge capacity, improved rate performance and cycling stability, surpassing Control622 and NMC111. Meanwhile, NMC811 also can be synthesized by the proposed strategy, and the discharge capacity can reach 166.9 mAh/g at 1C, similar to 14 mAh/g higher than Control811. Overall, this etching-assisted strategy simplifies the upcycling process and offers a scalable, sustainable route for producing high-quality cathode materials.

Inadvertent factors can sometimes be crucial for synthesis of catalysts. The use of polyalcohols is common in the synthesis of heterogeneous catalysts. Interactions between alcohols and heterogeneous catalysts have been shown to induce surface reconstructions that greatly impact catalytic performance. Thus, traces of these alcohol functionalities on the as-synthesized catalysts, combined with heat treatment, could be critical in the generation of catalytic sites. Here, we show that during the synthesis of a Ni-Mo/MgO catalyst using a polyol process, residual ethylene glycol (EG) on the surface plays a significant role in the generation of catalytic sites for dry reforming of methane (DRM). The as-synthesized catalyst presents dispersed cationic Ni. Under DRM reaction conditions, the presence of EG, and H2 generated in situ, promote the generation of co-localized Ni-Mo nanoparticles (NPs). Greater amount of EG in the as-synthesized catalyst prevented sintering, leading to better catalyst stability and higher rates. If the residual EG remaining post-synthesis is removed through calcination, before conducting DRM, NiO NPs are formed and the material is completely inactive for catalyzing the reaction. When using a different support, denoted MgO*, EG also proved indispensable to generate active sites, although Ni-Mo co-localization was not evident, and a combination of DRM-related species was needed to activate the catalyst, not just H2. This work systematically uncovers how the interactions between organic adsorbates, the supported metals and the catalyst support dictate the creation of catalytic active sites.

Silicon anodes have order of magnitude improvement in theoretical capacities over graphite counterparts for lithium-ion batteries. However, silicon exhibits large expansions upon lithiation, and the highly reducing environment deters the use of standard ethylene carbonate (EC) mixtures with lithium hexafluorophosphate (LiPF 6 ) salt. Indeed, highly soluble EC-derived polymer degradation products have been observed in both cell testing and model mechanistic studies. Thus, much effort has been made in solid electrode engineering and electrolyte design and optimization. In this vein, we developed EC-free electrolytes where large amounts of vinylene carbonate (VC) as a co-solvent with ethyl methyl carbonate (EMC) facilitated cycling stability in coin cell studies. 1 These electrolytes were further tested in ~2.3 Ah silicon oxide multilayer pouch cells and showed 80% capacity at 1,000 cycles, while cells that used EC-based electrolytes failed at ~400 cycles. 2 In this talk, we discuss the solution (neat) and solid electrode post-test analyses of these pouch cells. The VC-rich electrolyte was exceptionally clean after cycling, with no color and ca. 97% EMC by nuclear magnetic resonance spectroscopy (NMR). However, nearly all of the VC was consumed, and some polymerized VC was also observed. Fewer than ten lower-level products were observed by high-performance liquid chromatography mass spectrometry (HPLC-MS). On the other hand, the EC-containing electrolyte was dark brown with much less extractable volume and contained hundreds of species by the HPLC-MS analysis including fluorinated and non-fluorinated phosphates and EC-derived cyclic species and oligomers. On the electrode level, solid-phase NMR and X-ray photoelectron spectroscopies showed that the VC electrolyte electrodes had higher levels of lithium fluorophosphates (Li x PO y F z ), lower lithium fluoride, and fewer LiPF 6 degradation products. Overall, the combined solution and solid-state results indicate that the high concentration of VC aids in reducing the degradation cascade of PF 6 – anion in solution by favoring solid-phase fluorophosphates. The EC, conversely, appears to continually react at the surface, and undergoes full anion degradation as indicated by products such as phosphoric acid. Overall, these experiments point to the importance of electrolyte engineering for silicon anode systems and a transition away from conventional electrolyte designs based on ethylene carbonate. This research was supported by the U.S. Department of Energy’s Vehicle Technologies Office under the Silicon Consortium Project, directed by Brian Cunningham, Thomas Do, Nicolas Eidson and Carine Steinway, and managed by Anthony Burrell. The submitted manuscript has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (“Argonne”). Argonne, a U.S. Department of Energy Office of Science laboratory, is operated under Contract No. DE-AC02-06CH11357. The U.S. Government retains for itself, and others acting on its behalf, a paid-up nonexclusive, irrevocable worldwide license in said article to reproduce, prepare derivative works, distribute copies to the public, and perform publicly and display publicly, by or on behalf of the Government. 1. Woods, E. F.; Wu, D.; Robertson, L. A.; Liu, H.; Key, B.; Vaughey, J. T.; Zhang, Z. Electrolyte Design for Silicon-Based Li-Ion Battery Guided by Chemical Reactivity of Solvents with a Model Silicon Anode. ACS Appl. Energy Mater. 2024 , 7 , 8294. 2. Rodrigues, M.-T.; Trask, S.; Dunlop, A.; Lan, Y.-C.; Kubal, J.; Salpekar, D.; Prado, A. Y. R.; Wang, E.; McDaniel, C.; Robertson, L. A.; Tancin, R.; Schulze, M.; Folastre, N.; Key, B.; Zhang, Z.; Lu, W.; Abraham, D.; Jansen, A. Building high-energy silicon-containing batteries using off-the-shelf materials. J. Electrochem. Soc. 2025 , 172 , 120521.

The metal-support interface is central to governing catalytic transformations. While strong metal-support interaction (SMSI) is an established strategy to tailor the morphology and electronic properties of supported metal catalysts, the role of interfacial charge redistribution in SMSI formation remains poorly understood and rarely leveraged. Here, we report a dual-stimuli approach that combines pH modulation with ultrasonication to mediate SMSI construction in aqueous solution through dynamic Fermi level tuning. By leveraging in situ pH-driven charge redistribution at the metal-support interface, we achieve controllable SMSI encapsulation of metal nanoparticles, as verified by electrochemical analysis, work function measurements, and x-ray-based techniques. The resulting catalysts exhibit tunable SMSI features and deliver enhanced activity and selectivity in hydrogenation reactions. This work establishes a facile strategy to modulate catalyst structure and electronic properties by exploiting Fermi level variation as a driving force, thereby advancing rational SMSI design and catalytic performance across diverse environments.

Silicon (Si) is considered a promising replacement for graphite anodes in lithium-ion batteries (LIBs) due to its high abundance and exceptional specific capacity. However, widespread commercialization has been hindered by poor electrochemical performance. Among various strategies, the use of functional additives has emerged as one of the most effective and cost-efficient methods to enhance the electrochemical properties of LIBs. In this study, several additives─vinylene carbonate (VC), vinyl ethylene carbonate (VEC), lithium difluorophosphate (LiDFP), lithium difluoro(oxalato)borate (LiDFOB), lithium tetrafluorooxalatophosphate (LiTFOxP), and lithium difluorobis(oxalato)phosphate (LiDFBOP)─were systematically investigated in LiNi0.8Mn0.1Co0.1O2 (NMC811)||Si full cells. Notably, LiDFBOP, a lithium salt containing two oxalate groups, outperformed all other additives, delivering the best capacity retention after 300 cycles. Comprehensive characterizations, including FTIR, SEM, and XPS, revealed that LiDFBOP's superior performance stems from its ability to form a more stable solid electrolyte interphase (SEI) on the Si anode, owing to its favorable molecular structure that integrates the beneficial features of the other additives.

We report an electrochemical CO2 reduction reaction catalyzed by a paramagnetic and conductive CuO/Cu interface with spins polarized by a moderate external magnetic field (MF) of ∼800 gauss, achieving a ∼30% increase in CO2-to-C2+ Faradaic efficiency (FE) compared to that in the absence of the MF in a flow cell electrolyzer. At a current density of 400 mA/cm2, the CO2-to-C2+ FE reached 86.7 ± 2.7% with 47.9 ± 1.4% cathodic energy efficiency (EE) in contrast to the CO2-to-C2+ FE of 67.6% with 36.4% of EE in the absence of MF. Notably, ethanol production exhibits a much higher response to the MF (∼55.6% increase in FE) than ethylene (∼6.4% increase in FE) at 400 mA/cm2. In situ surface-enhanced Raman spectroscopy (SERS) captured magnetic-field-enhanced *CO coverage and ethanol-forming C2 intermediates on CuO/Cu, providing direct spectroscopic evidence of spin-modulated pathway selection. Computational study suggests that the enhancement of ethanol selectivity is due to the reduced reaction kinetic barrier under MF, while the ethylene selectivity is less affected, mainly due to the insensitivity of the kinetic barriers under MF.

Lithium and manganese-rich (LMR) layered oxides represent a leading class of high-energy cathode materials, but their practical realization is fundamentally limited by severe manganese (Mn) dissolution, a process that triggers structural degradation and rapid capacity fade. While mitigation efforts have predominantly focused on interfacial engineering, the intrinsic contribution of bulk electrolyte solvation to this degradation pathway remains largely unexplored, primarily due to the difficulty of deconvolving its effects from concurrent cathode-electrolyte interphase (CEI) formation. Here, we report an experimental design to isolate the role of solvation. We systematically varied the electrolyte solvent solvation power by substituting the strongly coordinating ethylene carbonate (EC) with its weaker coordinating fluorinated derivatives, fluoroethylene carbonate (FEC) and trans-4,5-Difluoro-1,3-dioxolan-2-one (DFEC), while maintaining a consistent interfacial chemistry. Remarkably, the electrolyte formulated with the weakest solvent, DFEC, exhibits superior cycling stability, suppressing Mn dissolution by up to 63% relative to the conventional EC-based system. Post-mortem analysis unequivocally attributes this performance enhancement to the preservation of the LMR cathode's structural integrity, a direct consequence of mitigated Mn dissolution. This work provides conclusive evidence that modulating bulk electrolyte solvation is a potent and direct strategy for stabilizing LMR cathodes, establishing a vital design principle for next-generation battery systems.

As fast-charging technology expands across the electric vehicle and emerging energy-storage applications, understanding its impact on battery performance and longevity is critical. In this study, 1.8 Ah LiNi0.6Mn 0.2Co 0.2O2/graphite pouch cells were charged at various charging rates (0.5C, 2C, 4C, and 6C) to investigate the degradation mechanisms. Our results showed that well-designed NMC/Gr pouch cells could reach over 1000 cycles with a 2C charging rate, while only reaching around 500 cycles with 4C and 6C charging rates. Fast-charging effects on NMC and graphite electrodes were obtained through a series of post-mortem characterizations, including electrochemical impedance spectroscopy (EIS), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS). Although higher charging rates cause pulverization of NMC secondary particles, the dominant degradation mechanism driving the fading of fast-charging-related performance lies in the graphite anode, where lithium plating and LiF-rich solid electrolyte interphase (SEI) formation result in Li inventory loss and impedance growth. The postmortem results suggest that the formation of a LiF-rich SEI, which exacerbates anode impedance and some irreversible Li+ ion loss, is likely driven by the substantial decomposition of PF6- during fast charging, an effect often overlooked in smaller laboratory-scale studies.

The rapid growth of lithium-ion battery (LIB) deployment presents critical challenges in sustainable end-of-life management and raw material recovery. Conventional pyrometallurgical and hydrometallurgical methods suffer from high energy demand, lithium loss, and complex wastewater treatment. This study established a universal, highly efficient, and sustainable hydrothermal route for lithium extraction and material recovery from various spent lithium-ion battery cathodes using 1,2,4,5-benzenetetracarboxylic acid (BTCA). The optimized process achieved over 99% lithium leaching efficiency for lithium iron phosphate (LFP) and LiNi x Mn y Co1-x- y O2 (NMC), with transition metal coleaching below 1%. It was also broadly applicable to lithium manganese oxide, lithium cobalt oxide, and black mass, achieving 98.5%, 98.95%, and 94.06% leaching efficiencies, respectively. The extracted lithium was directly converted into battery-grade lithium sources, while transition metals were recovered as oxides. Unreacted BTCA was efficiently regenerated and reused without degradation. Electrochemical evaluation confirmed that cathode materials synthesized with recovered lithium exhibit comparable performance to commercial products. Compared to conventional hydrometallurgy, the BTCA-based process increased revenue by over 40% and reduced greenhouse gas emissions by up to 39%. This closed-loop, chemistry-agnostic strategy offered a scalable and economically viable solution for industrial LIB recycling, enabling resource circularity and reducing dependency on primary critical materials.

Polyethylene was recycled into carbon materials via tandem cross-linking and carbonization using sodium amide, enabling C–H bond cleavage and C–N bond formation, and these materials showed good performance in gas separation and energy storage.