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

Abstract

In this paper, lithium hexaoxotungstate (LiWO) nanowires were synthesized via facile solid-state reaction and were tested for CO capture applications at both low (<100 °C) and high temperatures (>700 °C). Under dry conditions, the nanowire materials were able to capture CO with a weight increment of 12% in only 60 s at an operating temperature of 710 °C. By contrast, under humidified ambience, LiWO nanowires capture CO 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 CO chemisorption in LiWO 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 LiWO, 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 LiWO materials highly suitable for various CO capture applications.

CO2 capture using solid sorbents: Fundamental aspects, mechanistic insights and recent advances

“…The common finding is that as diffusion of O 2from the bulk sorbent to the surface is the main kinetic limiting factor for the formation of a carbonate phase, the addition of O2 to the gas phase improves the availability of O2 for carbonation, increasing the absorption rate and overall capacity. This effect was observed for a range of materials including Li6WO6 nanowires [464], Li5FeO4 [473] and Li5AlO4 [582], [583], with activation energies for O 2diffusion derived from CO2 absorption measurements again in line with experimental values of 1 -2 eV.…”

Lithium silicate nanosheets with excellent capture capacity and kinetics with unprecedented stability for high-temperature CO2 capture

“…5 In addition to the formation of thick carbonate shells, the sintering of sorbent particles was another reason for the fast decline in capture capacity and kinetics in conventional silicates. 8,9 In the LSN sorbent, due to the absence of any carbonate shell, CO 2 desorption was very efficient (nearly 100%, Fig. 3a).…”

“…Recently, nanowires of lithium silicates and lithium tungstate showed good kinetics of CO 2 capture. 8,9 However, these nanowires were not stable against agglomeration/sintering during the high-temperature CO 2 adsorption-desorption process, with a loss of 50% of their capture performance (capacity and kinetics) in the rst three cycles. Thus, there was a need for a sorbent that has the following properties: (i) high CO 2 capture at elevated temperatures (between 600 and 750 C), (ii) faster rate of adsorption/desorption, and (iii) cycling stability for hundreds of CO 2 capture-release cycles.…”

A new nanowire-based lithium hexaoxotungstate anode for lithium-ion batteries

“…Fortunately, current research has introduced a variety of functional materials with 1D morphologies that could be prepared via cost-effective and easily scalable procedures. [24][25][26] Anodes based on tungsten oxide (WO 3 ) and its composites, in particular, have drawn immense attention from researchers as they offer high specic capacities. 27 WO 3 materials with monoclinic and hexagonal structures with varying morphologies have been thoroughly investigated for LIB applications.…”