Lithium hydroxide as a high capacity adsorbent for CO2 capture: experimental, modeling and DFT simulation

In this work, the potential of monohydrate Lithium hydroxide (LiOH) as a high capacity adsorbent for CO₂ capture was investigated experimentally and theoretically. The effects of operating parameters, including temperature, pressure, LiOH particle size and LiOH loading, on the CO₂ capture in a fixed-bed reactor have been experimentally explored using response surface methodology (RSM) based on central composite design. The optimum conditions obtained by the RSM for temperature, pressure, mesh and maximum adsorption capacity were calculated as 333 K, 4.72 bar, 200 micron and 559.39 mg/g, respectively. The experiments were evaluated using isotherm, kinetic and thermodynamic modeling. Isotherm modeling showed that Hill model could deliver a perfect fit to the experimental data, based on the closeness of the R²-value to unity. The kinetics models showed that the process was chemical adsorption and obeyed the second order model. In addition, thermodynamic analysis results showed that the CO₂ adsorption was spontaneous and exothermic in nature. In addition, based on the density functional theory, we investigated the chemical stability of LiOH atomic clusters and examined the effects of LiOH nanonization on the physical attraction of carbon dioxide.

Enhanced Cycling Performance of a Li-Excess Li2CuO2 Cathode Additive by Cosubstitution Nanoarchitectonics of Ni and Mn for Lithium-Ion Batteries

The adoption of Li₂CuO₂ has drawn interest as a Li-excess cathode additive for compensating irreversible Li⁺ loss in anodes during cycling, which would move forward high-energy-density lithium-ion batteries (LIBs). Li₂CuO₂ provides a high irreversible capacity (>200 mAh g^-1) in the first cycle and an operating voltage comparable with commercial cathode materials, but its practical use is still restricted by the structural instability and spontaneous oxygen (O₂) evolution, resulting in poor overall cycling performance. It is thus crucial to reinforce the structure of Li₂CuO₂ to make it more reliable as a cathode additive for charge compensation. Pursuing the structural stability of Li₂CuO₂, herein, we demonstrate cosubstitution by heteroatoms, such as nickel (Ni) and manganese (Mn), for improving the structural stability and electrochemical performance of Li₂CuO₂. Such an approach effectively enhances the reversibility of Li₂CuO₂ by suppressing continuous structural degradation and O₂ gas evolution during cycling. Our findings provide new conceptual pathways for developing advanced cathode additives for high-energy LIBs.

CO2 Capture at Medium to High Temperature Using Solid Oxide-Based Sorbents: Fundamental Aspects, Mechanistic Insights, and Recent Advances

Carbon dioxide capture and mitigation form a key part of the technological response to combat climate change and reduce CO₂ emissions. Solid materials capable of reversibly absorbing CO₂ have been the focus of intense research for the past two decades, with promising stability and low energy costs to implement and operate compared to the more widely used liquid amines. In this review, we explore the fundamental aspects underpinning solid CO₂ sorbents based on alkali and alkaline earth metal oxides operating at medium to high temperature: how their structure, chemical composition, and morphology impact their performance and long-term use. Various optimization strategies are outlined to improve upon the most promising materials, and we combine recent advances across disparate scientific disciplines, including materials discovery, synthesis, and in situ characterization, to present a coherent understanding of the mechanisms of CO₂ absorption both at surfaces and within solid materials.

Lithium cuprate, a multifunctional material for NO selective catalytic reduction by CO with subsequent carbon oxide capture at moderate temperatures

Li2CuO2 was evaluated as a possible catalyst for the NO selective catalytic reduction (NO SCR) by CO.

Evaluation of Fe-containing Li2CuO2 on CO2 capture performed at different physicochemical conditions

Li₂CuO₂ and different iron-containing Li₂CuO₂ samples were synthesized by solid state reaction. On iron-containing samples, atomic sites of copper are substituted by iron ions in the lattice (XRD and Rietveld analyses). Iron addition induces copper release from Li₂CuO₂, which produce cationic vacancies and CuO, due to copper (Cu²⁺) and iron (Fe³⁺) valence differences. Two different physicochemical conditions were used for analyzing CO₂ capture on these samples; (i) high temperature and (ii) low temperature in presence of water vapor. At high temperatures, iron addition increased CO₂ chemisorption, due to structural and chemical variations on Li₂CuO₂. Kinetic analysis performed by first order reaction and Eyring models evidenced that iron addition on Li₂CuO₂ induced a faster CO₂ chemisorption but a higher thermal dependence. Conversely, CO₂ chemisorption at low temperature in water vapor presence practically did not vary by iron addition, although hydration and hydroxylation processes were enhanced. Moreover, under these physicochemical conditions the whole sorption process became slower on iron-containing samples, due to metal oxides presence.

Low-Temperature and Fast Kinetics for CO2 Sorption Using Li6WO6 Nanowires

In this paper, lithium hexaoxotungstate (Li₆WO₆) nanowires were synthesized via facile solid-state reaction and were tested for CO₂ capture applications at both low (<100 °C) and high temperatures (>700 °C). Under dry conditions, the nanowire materials were able to capture CO₂ with a weight increment of 12% in only 60 s at an operating temperature of 710 °C. By contrast, under humidified ambience, Li₆WO₆ nanowires capture CO₂ with weight increment of 7.6% at temperatures as low as 30-40 °C within a time-scale of 1 min. It was observed that the CO₂ chemisorption in Li₆WO₆ is favored in the oxygen ambience at higher temperatures and in the presence of water vapor at lower temperatures. Nanowire morphology favors the swift lithium supply to the surface of lithium-rich Li₆WO₆, thereby enhancing the reaction kinetics and lowering time scales for high capacity adsorption. Overall, high chemisorption capacities, superfast reaction kinetics, wide range of operating temperatures, and reasonably good recyclability make 1-D Li₆WO₆ materials highly suitable for various CO₂ capture applications.

Kinetic analysis for cyclic CO2 capture using lithium orthosilicate sorbents derived from different silicon precursors

The illustration of the CO₂ sorption process in Li₄SiO₄.

CO2 chemisorption in Li2CuO2 microstructurally modified by ball milling: study performed with different physicochemical CO2 capture conditions

Lithium cuprate (Li₂CuO₂) was obtained by a solid state reaction and a subsequent ball milling process. Then, the samples were characterized (structurally and microstructurally) and evaluated as CO₂ captors.

Structural and CO2capture analyses of the Li1+xFeO2(0 ≤ x ≤ 0.3) system: effect of different physicochemical conditions

α-Li_1+xFeO₂compounds have been synthesized by nitrate decomposition at low temperature. Their CO₂capture were evaluated in CO₂and CO₂+ steam atmospheres. The amount captured in CO₂+ steam atmosphere was 24 wt%, also magnetite was formed.

Bifunctional application of sodium cobaltate as a catalyst and captor through CO oxidation and subsequent CO2 chemisorption processes

Sodium cobaltate works as a bifunctional material, in the catalysis of CO oxidation and subsequent CO₂ chemisorption.