Efficient CO₂ capture at concentrations between 400–2000 ppm is essential for maintaining air quality in a habitable environment and advancing carbon capture technologies. This study introduces NICS‐24 (National Institute of Chemistry Structures No. 24), a Zn‐oxalate 3,5‐diamino‐1,2,4‐triazolate framework with two distinct square‐shaped channels, designed to enhance CO₂ capture at indoor‐relevant concentrations. NICS‐24 exhibits a CO₂ uptake of 0.7 mmol/g at 2 mbar and 25 °C, significantly outperforming the compositionally related Zn‐oxalate 1,2,4‐triazolate – CALF‐20 (0.17 mmol/g). Improved performance is attributed to amino‐functions that enhance CO₂ binding and enable superior selectivity over N₂ and O₂, achieving 8‐fold and 30‐fold improvements, respectively, in simulated CO₂/N₂ and CO₂/O₂ atmospheric ratios. In humid environments, NICS‐24 retained structural integrity but exhibited an 85 % reduction in CO₂ capacity due to competitive water adsorption. Breakthrough sorption experiments, atomistic NMR analysis, and DFT calculations revealed that water preferentially adsorbs over CO₂ due to strong hydrogen‐bonding interactions within the framework. Gained understanding of the interaction between CO₂ and H₂O within the MOF framework could guide the modification via rational design with improved performance under real‐world conditions.

The sustainable generation of energy and low-energy consuming technologies are two main approaches to combat climate change and reduce carbon dioxide emissions. Sorption heat storage is part of the second approach. Therefore, adsorbents that achieve high energy storage density under the working conditions of the storage application are required. In this study, the hydrophilic properties of a granulated binder-free zeolite NaY were tailored with the aim of increasing its performance at a desorption temperature of 140 °C for mobile sorption heat storage. Top-down approaches, such as chemical treatment with the chelating agent H₄EDTA, treatment with the inorganic acid HCl and sequential ion exchange with acid treatment, were used in order to decrease the desorption temperature and optimize the low-temperature heat storage density. All the modified samples showed a decrease in the desorption temperature from 10 to 30 °C compared to the parent sample; only the desorption temperature of the acid-treated Mg-exchanged NaY sample increased. The effect of different treatments on the structural properties of the materials, including the generation of framework defects and mesoporosity was determined. The energy storage densities of the NaY and all the modified samples are considerably higher in comparison to the currently used adsorbent (NaMSX) in mobile sorption heat storage for low-temperature industrial waste heat recovery.

Hard carbons are promising negative electrode materials for Na-ion batteries (SIBs), and the process of (de)insertion of Na⁺ ions into/from hard carbons has attracted much attention in recent research. Because of being a relatively new technology compared to lithium-ion batteries, the precise operational mechanism and degradation pathways of SIBs remain elusive. In this investigation, we focus on elucidating the physical and electrochemical attributes of corncob-derived hard carbon synthesized at 1400°C using operando and ex-situ solid-state NMR spectroscopy techniques, complemented by other advanced characterization methods, such as SEM-EDX, XPS and electrochemistry. Through the analysis of ²³Na NMR spectra of hard carbon, we gained insights into sodium insertion within the active material, which is characterized by the shifting NMR peak during the (de)sodiation process. Furthermore, our findings revealed the formation of a solid electrolyte interphase (SEI) at the hard carbon electrode and pore surface, predominantly in the form of Na₂CO₃ in the bulk of the SEI, and NaF at the SEI surface, alongside the occurrence and differentiation of plating and metal sodium dendrites.