Ion-Exchangeable Molybdenum Sulfide Porous Chalcogel: Gas Adsorption and Capture of Iodine and Mercury

Abstract

We report the synthesis of ion-exchangeable molybdenum sulfide chalcogel through an oxidative coupling process, using (NH4)2MoS4 and iodine. After supercritical drying, the MoS(x) amorphous aerogel shows a large surface area up to 370 m(2)/g with a broad range of pore sizes. X-ray photoelectron spectroscopic and pair distribution function analyses reveal that Mo(6+) species undergo reduction during network assembly to produce Mo(4+)-containing species where the chalcogel network consists of [Mo3S13] building blocks comprising triangular Mo metal clusters and S2(2-) units. The optical band gap of the brown-black chalcogel is ∼1.36 eV. The ammonium sites present in the molybdenum sulfide chalcogel network are ion-exchangeable with K(+) and Cs(+) ions. The molybdenum sulfide aerogel exhibits high adsorption selectivities for CO2 and C2H6 over H2 and CH4. The aerogel also possesses high affinity for iodine and mercury.

Molybdenum Polysulfide Chalcogels as High-Capacity, Anion-Redox-Driven Electrode Materials for Li-Ion Batteries

“…Collecting operando PDFs allows for tracking the evolution of the local structure for materials that lack long-range ordering, which is particularly useful for chalcogels. 48,[72][73][74][75][76][77] Here, PDFs of the MoS x electrode cycled at constant current of 0.61 (9) mA g −1 (≈ C/16) (Figure 8a) capture the Mo-S bonds centered at 2.45Å in Figure 8b, which is unchanged upon discharge to 600.5 mAh g Coulombic efficiency is maintained at 98.9% for the second and third cycles. One of the many strategies for increasing Li ion kinetics includes increasing the electrode surface area.…”

Modern Inorganic Aerogels

“…[40][41][42] Mechanistically,this method is comparable to the classical gel formation since the clusters used have am olecular size and form ap olymer-like network. [45][46][47][48][49] However,t aking stable colloidal solutions of metal chalcogenides and assembling them into macroscopic structures,d irectly opened an ew field of research. [45][46][47][48][49] However,t aking stable colloidal solutions of metal chalcogenides and assembling them into macroscopic structures,d irectly opened an ew field of research.…”

Fine-tuning of the confined space in microporous metal–organic frameworks for efficient mercury removal

“…Therefore, there is an urgent need for novel efficient methods to capture mercury, selectively. [31][32][33][34][35][36][37] MOFs are showing themselves recently as very attractive materials in this area.…”