Synthesis of niobium(iv) carbide nanoparticles an alkali-molten-method at a spatially-limited surface of mesoporous carbon.

One-pot synthesis of niobium carbabide (NbC) nanoparticles with 30-50 nm was achieved a rationally designed novel alkali-molten salt method using niobium oxide (NbO), potassium carbonate (KCO), and mesoporous carbon (MPC). In this reaction, potassium niobate (KNbO) was produced as an intermediate and carbonization of KNbO proceeds at a spatially limited external surface encompassed by the mesopores of MPC due to the repulsive characteristics of ionic KNbO toward hydrophobic MPC, which affords the size-controlled NbC nanoparticles with a narrow particle distribution. The particle sizes tended to become smaller as the pore sizes of MPCs or the temperature on the calcination under the nitrogen stream decreased.

Highly stable Fe/CeO catalyst for the reverse water gas shift reaction in the presence of HS.

This study focused on evaluating the catalytic properties for the reverse water gas shift reaction (RWGS: CO + H → CO + HO Δ = 42.1 kJ mol) in the presence of hydrogen sulfide (HS) over a Fe/CeO catalyst, commercial Cu-Zn catalyst for the WGS reaction (MDC-7), and Co-Mo catalyst for hydrocarbon desulfurization. The Fe/CeO catalyst exhibited a relatively high catalytic activity to RWGS, compared to the commercial MDC-7 and Co-Mo catalysts.

Photo-induced mode change for CO capture/release on spiropyran in a polar-gradient environment.

Photo-induced mode change of CO capture/release was achieved by a rationally designed system composed of spiropyran introduced into a polar-gradient field in the interlayer of montmorillonite. DFT calculations and CO adsorption tests demonstrated that spiropyran can interact with CO through not only weak physical interaction such as Coulombic or van der Waals interactions but also electronic interaction, while photo-isomerized merocyanine was in the CO release mode. Photo-induced CO concentration systems highly contribute to the realization of carbon neutrality, hence, this study could be a breakthrough for the world's environmental issues.

Dual mechanoluminescence system comprising a solid-state di-copper(I) complex containing N-heterocyclic carbene ligands.

A simple N-heterocyclic carbene (NHC) ligand linked to a flexible propylene linker allows the formation of "Cu-Cu"- and "2 Cu"-type geometries inside a molecular framework. The incorporation of two Cu(i) ions in close proximity was observed in the Cu-Cu-type geometry but not in the 2 Cu-type geometry. In this study, the ground-state geometries of solid-state di-copper(i) complexes containing NHC ligands with ethyl substituents were modulated by external stimuli.

Sorption of As(V) from aqueous solution using acid modified carbon black.

The sorption performance of a modified carbon black was explored with respect to arsenic removal following batch equilibrium technique. Modification was accomplished by refluxing the commercial carbon black with an acid mixture comprising HNO(3) and H(2)SO(4). Modification resulted in the substantial changes to the inherent properties like surface chemistry and morphology of the commercial carbon black to explore its potential as sorbent.

Arsenic adsorption from aqueous solution on synthetic zeolites.

The adsorption of arsenic from aqueous solution on synthetic zeolites H-MFI-24 (H24) and H-MFI-90 (H90) with MFI topology has been investigated at room temperature (r.t) applying batch equilibrium techniques. The influences of different sorption parameters such as contact time, solution pH, initial arsenic concentration and temperature were also studied thoroughly in order to optimize the reaction conditions.

Adsorption of As(V) on surfactant-modified natural zeolites.

Natural mordenite (NM), natural clinoptilolite (NC), HDTMA-modified natural mordenite (SMNM) and HDTMA-modified natural clinoptilolite (SMNC) have been proposed for the removal of As(V) from aqueous solution (HDTMA=hexadecyltrimethylammonium bromide). Influence of time on arsenic sorption efficiency of different sorbents reveals that NM, NC, SMNM and SMNC require about 20, 10, 110 and 20h, respectively to reach at state of equilibrium. Pseudo-first-order model was applied to evaluate the As(V) sorption kinetics on SMNM and SMNC within the reaction time of 0.

Surface-modified carbon black for As(V) removal.

This paper reports the results of the adsorption performance of As(V) removal by a commercial carbon black and its H2SO4-modified form in a single-ion situation. The influence of different process parameters and the physicochemical principles involved were studied in detail. Acid modification caused morphological changes in the virgin carbon black as evidenced by BET surface area measurements and SEM study.

Mechanistic study on adsorptive removal of tert-butanethiol on Ag-Y zeolite under ambient conditions.

The dynamics and surface chemistry of tert-butanethiol (TBT) adsorptive removal over silver-exchanged Y zeolite (Ag-Y) were studied under ambient conditions. Saturation uptake on Ag-Y was higher than that on H-Y and Na-Y. The structural analyses by a combination of X-ray diffraction, Ag K-edge X-ray absorption near-edge structure (XANES)/extended X-ray absorption fine structures (EXAFS), Ag L(III)-edge XANES, S K-edge XANES, and in situ UV-vis show that the AgSH molecule, Ag(2)S monomer, and Ag(4)S(2) cluster are the dominant silver species in TBT-saturated Ag-Y.