Dielectric Characterization of HO and CO Uptake by Polyethylenimine Films.

The absorption of CO by polyethylenimine polymer (PEI) materials is of great interest in connection with proposed carbon capture technologies, and the successful development of this technology requires testing methods quantifying the amount of CO, HO, and reaction byproducts under operating conditions. We anticipate that dielectric measurements have the potential for quantifying both the extent of CO and HO absorption within the PEI matrix material as well as insights into subsequent reaction byproducts that can be expected to occur in the presence of moisture. The complexity of the chemistry involved in this reactive binding process clearly points to the need for the use of additional spectroscopic techniques to better resolve the multiple components involved and to validate the model-dependent findings from the dielectric measurements.

Thickness Dependent CO Adsorption of Poly(ethyleneimine) Thin Films for Direct Air Capture.

Mesoporous silica impregnated with polyethyleneimine (PEI) has been shown to be a suitable material for the direct air capture (DAC) of CO. Factors such as CO concentration, temperature, and amine loading impact overall capture capacity and amine efficiency by altering diffusional resistance and reaction kinetics. When studied in the impregnated 3-dimensional sorbent material, internal diffusion impacts the evaluation of the reaction kinetics at the air/amine interface.

Phosphate-functionalized Zirconium Metal-Organic Frameworks for Enhancing Lithium-Sulfur Battery Cycling.

Lithium-sulfur batteries are promising candidates for next-generation energy storage devices due to their outstanding theoretical energy density. However, they suffer from low sulfur utilization and poor cyclability, greatly limiting their practical implementation. Herein, we adopted a phosphate-functionalized zirconium metal-organic framework (Zr-MOF) as a sulfur host.

Polymer-Regulated Electrochemical Reduction of CO on Ag.

The influence of polymer overlayers on the catalytic activity of Ag for electrochemical CO reduction to CO is explored. Polystyrene and poly(4-vinylpyridine) films of varying thicknesses are applied as catalysis-directing overlayers atop Ag electrodes. For polystyrene, substantial suppression of CO reduction activity is observed while the hydrogen evolution reaction (HER) increases.

Chemical Sulfide Tethering Improves Low-Temperature Li-S Battery Cycling.

Demands for energy storage and delivery continue to rise worldwide, making it imperative that reliable performance is achievable in diverse climates. Lithium-sulfur (Li-S) batteries offer a promising alternative to lithium-ion batteries owing to their substantially higher specific capacity and energy density. However, improvements to Li-S systems are still needed in low-temperature environments where polysulfide clustering and solubility limitations prohibit complete charge/discharge cycles.

Graphene-Metal-Organic Framework Composite Sulfur Electrodes for Li-S Batteries with High Volumetric Capacity.

In an age of rapid acceleration toward next-generation energy storage technologies, lithium-sulfur (Li-S) batteries offer the desirable combination of low weight and high specific energy. Metal-organic frameworks (MOFs) have been recently studied as functionalizable platforms to improve Li-S battery performance. However, many MOF-enabled Li-S technologies are hindered by low capacity retention and poor long-term performance due to low electronic conductivity.

Lithium Thiophosphate Functionalized Zirconium MOFs for Li-S Batteries with Enhanced Rate Capabilities.

Zirconium metal-organic frameworks (Zr-MOFs) are renowned for their extraordinary stability and versatile chemical tunability. Several Zr-MOFs demonstrate a tolerance for missing linker defects, which create "open sites" that can be used to bind guest molecules on the node cluster. Herein, we strategically utilize these sites to stabilize reactive lithium thiophosphate (LiPS) within the porous framework for targeted application in lithium-sulfur (Li-S) batteries.

Lithiated Defect Sites in Zr Metal-Organic Framework for Enhanced Sulfur Utilization in Li-S Batteries.

Lithium sulfur (Li-S) battery technology is one of the most promising candidates for next-generation energy storage devices; however, it is still hindered by limited capacity yield and poor long-term stability. The complexity of these devices has hindered efforts to study electrochemical determinants of battery performance, impeding advancement of the field. Due to the ease of functionalization, metal-organic frameworks (MOFs) are unique platforms to explore such reactions, where integration of defects into the crystalline structure provides a convenient method for introducing synthetic handles.