Watchareeya Kaveevivitchai

The development of advanced physisorption-based adsorbents is essential for carbon dioxide (CO2) capture technologies. While metal–organic frameworks (MOFs) offer a promising alternative to traditional carbon capture methods, they often face a trade-off between high adsorption affinity and energy-intensive regeneration. In this work, we report an anionic copper–triazolate framework, NCKU-56 (NCKU = National Cheng Kung University), incorporating quinone-based organic linkers. The 1D channels exhibit moderate structural flexibility and reversible lattice adjustments that are specifically correlated with CO2 adsorption. This material demonstrates high CO2/N2 IAST selectivity of 65 and 315 (50/50, 15/85, v/v) at 298 K and a moderate isosteric heat of adsorption of 30.1 kJ mol–1, which facilitates rapid regeneration without high thermal energy penalties. Crystallographic analysis reveals that the selective uptake is driven by cooperative host–guest interactions, including quadrupole−π interactions (with quinone cores and triazolate rings) and hydrogen bonding between CO2 and [NH2(CH3)2]+ cations. Breakthrough experiments confirm the practical efficacy of NCKU-56 for CO2/N2 separation, highlighting the potential of integrating polar functional groups and π systems with moderate framework flexibility for energy-efficient carbon capture.

The development of high-energy-density lithium-ion batteries (LIBs) is crucial to meet the increasing demands of electric vehicles (EVs), hybrid electric vehicles (HEVs), portable electronics, and large-scale energy storage systems. In this context, dry electrode fabrication has emerged as a sustainable and cost-effective alternative to conventional slurry-based processing, particularly for high-loading thick electrodes. However, intensive calendaring required in dry thick electrode processing induces significant mechanical stress, often leading to particle cracking in nickel-rich layered oxide cathodes and consequent electrochemical degradation. Herein, we systematically investigated the mechanical robustness and electrochemical performance of single-crystal S-LiNi0.8Co0.1Mn0.1O2 (S-NCM811) cathodes fabricated via a dry electrode route. The single-crystal S-NCM811 demonstrates superior structural integrity with significantly reduced particle cracking after calendaring, as confirmed by SEM analysis. Electrochemical evaluations reveal enhanced lithium-ion transport kinetics, lower charge-transfer resistance, and improved porosity in S-NCM811 compared to its polycrystalline counterpart. As a result, the S-NCM811 dry thick electrode achieves a high-capacity retention of 91.5% at 0.5 C after 50 cycles at a high mass loading of ∼35 mg cm–2, as compared to P-NCM811, which retained only 63.4% of its initial capacity after subsequent cycles. This work highlights the critical role of crystal morphology in mitigating mechanical degradation during dry processing and provides valuable insights into the design of robust nickel-rich cathodes for next-generation high-energy-density LIBs.

Aqueous-based batteries are among the most promising candidates for sustainable energy storage due to cost, safety and environmental perspective. Apart from charge carriers, e.g., Li⁺, Na⁺, K⁺, Mg²⁺ and Zn²⁺, which have been predominantly explored for aqueous systems, non-metallic charge carriers, proton (H⁺), have recently gained major attention. Combining with organic electrode materials, which feature redox tunability, structural design flexibility as well as rapid redox kinetics and come from abundant/renewable resources, truly sustainable batteries can be materialized. Herein, we report a nitrogen-and carbonyl-rich highly π-conjugated organic small molecule, hexaazatrianthranylene (HATA) embedded quinone (HATAQ), with a 2D supramolecular layered structure held together by hydrogen bonding and π-π interactions, as electrode for aqueous proton batteries. Experimental characterization results, including various kinetic studies, together with molecular and periodic density functional theory (DFT) calculations, reveal Grotthuss fast proton conduction in the hydrogen-bonded network as HATAQ undergoes multistep proton-coupled electron transfer reactions. The compound possesses excellent proton storage capability, delivering a capacity as high as 310 mAh g^-1 at 0.75 A g^-1 with exceptional cycling stability retaining 90% of its capacity after 10000 cycles at a high rate of 20 A g^-1. All-organic full cells with the HATAQ anode and tetrachloro-1,4-benzoquinone (TCBQ) cathode have also been utilized to demonstrate their suitability for practical applications. The unique interplay between highly dense proton-storing imine and carbonyl redox sites and hydrogen-bonded supramolecular network creates pathways for very fast proton transport, exhibiting ultra-high capacity and rate capability as well as unparalleled cycling stability in aqueous proton batteries.

A permanently porous TPDA-Ph-BDT conjugated microporous polymer cathode enables high capacity and ultralong cycling stability in aqueous Zn batteries, delivering 154 mA h g ⁻¹ and 96% retention over 50 000 cycles at 20 A g ⁻¹ .

A new UiO-66 derivative MOF, UiO-66-F ₂ (OH) ₂ , which integrates fluorine and hydroxyl groups for enhancing propylene/propane separation.

Lithium-ion batteries serve as a key technology, establishing the advancement of energy storage devices and playing a vital role in the global shift toward sustainable and green energy. However, the growing demand for high capacity nickel (Ni)-rich lithium-ion batteries accelerates the optimization of their energy density. A high-mass loading electrode design is a promising strategy for enhancing the energy density of LIBs, enabling the improved performance for commercial applications. The factors that limit the rate capability of the high-mass loading electrode are associated with the underutilization of active materials and increased polarization, which can be further attributed to slow electronic/ionic transport within the electrode. In this work, the conductive networks and porous characteristics of the Ni-rich LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) cathode electrode is preciously tailored through the incorporation of multidimensional carbon conductive additives, facilitating enhanced electron transport and optimized porosity enhancing lithium-ion diffusion within the high-mass loading electrode. As a result, the NCM811 cathode electrode with dual-multidimensional conductive additives, such as carbon black and carbon nanofiber (CB + CNF), exhibits an outstanding performance, achieving a capacity retention of 94.8% over 100 cycles at 1 C. It is also observed that long-structured CNFs contributes significantly to the formation of efficient conductive networks in a high-mass loading thick electrode (∼23 mg cm^-2) exhibiting excellent performance at 0.2 C. The simple yet fundamental principle uncovered through this work demonstrates that the integration of the dual-carbon system synergistically enhances the conductive networks and optimizes electrode porosity. This microstructural optimization effectively reduces Ohmic contact resistance, contributing to a significantly enhanced electrochemical performance.

This study reports on the rational design of hydroxyl-functionalized covalent organic framework nanofibers (HO-COFs: PyTA-2,3-NA(OH)₂ and PyTA-2,6-NA(OH)₂) by a scalable solvothermal method. The resulting PyTA-2,3-NA(OH)₂ HO-COF is more hydrophilic than the PyTA-2,6-NA(OH)₂ HO-COF, which can effectively enhance the sensitivity of the sensor toward basic ethylenediamine (EDA). The fabricated HO-COF nanofiber-based quartz crystal microbalance sensor exhibits a rapid sensing response and a distinguished selectivity toward EDA vapor, arising from the strong hydrogen bonding interactions with the NH₂ groups of EDA, as investigated by a wide variety of chemical analysis techniques and density functional theory calculations. The presence of exposed neighboring hydroxyl groups that face the same direction in the PyTA-2,3-NA(OH)₂ HO-COF and the NH₂ groups present in EDA exhibited efficient interactions. The PyTA-2,3-NA(OH)₂ nanofiber with neighboring hydroxyl groups exhibits 1.6 times higher sensitivity to 100 ppm (ppm) EDA than PyTA-2,6-NA(OH)₂ with hydroxyl groups in opposite directions, with a low limit of detection of 2.9 ppm. The PyTA-2,3-NA(OH)₂ nanofiber structure has abundant active neighboring hydroxyl groups facing the same direction, making them favorable active sites for binding EDA molecules through strong hydrogen bond interactions. The color of the HO-COF changed after exposure to EDA vapor, as investigated by colorimetric assessment and naked-eye detection. These HO-COF nanofibers exhibit remarkable selectivity for EDA in the presence of other interfering chemical vapors and show high stability with only a 6.4% drop in sensitivity after 6 months. The adsorption of EDA on PyTA-2,3-NA(OH)₂ nanofibers follows a pseudo-first-order kinetic model, with an adsorption rate about 8.0 times faster than PyTA-2,6-NA(OH)₂ nanofibers. The findings of this study highlight the potential use of COFs, particularly those nanofibers with close neighboring hydroxyl groups, as effective sensing materials for the selective detection of harmful EDA.