Herein, we report a synthesis method for highly porous molybdenum oxide via molybdenum-oxo cluster formation under acidic conditions providing extraordinary stability. Synthesized materials indicate higher valences of molybdenum as compared to the commercial standards as verified through X-ray photoelectron spectroscopy, electron paramagnetic resonance spectroscopy, and ultraviolet–visible spectroscopy. The formation of a 91% orthorhombic molybdenum oxide bulk structure was verified through powder X-ray diffraction analysis. The effect of the hydrogen peroxide solvent system was optimized to obtain pore diameters as big as 17.4 nm and pore volumes as high as 0.168 cm3/g. These materials serve as great catalysts providing excellent yields of imine via amine coupling, having first-order kinetics with a turnover number as good as 27.93 with a slight decrease to 22.04 even after the fourth cycles. Surface hydroxyl species on the catalyst aid in the solid acid catalysis to jump-start the reaction.

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Carbon capture and storage (CCS) technologies have the potential for reducing greenhouse gas emissions and creating clean energy solutions. One of the major aspects of the CCS technology is designing energy-efficient adsorbent materials for carbon dioxide capture. In this research, using a combination of first-principles theory, synthesis, and property measurements, we explore the CO2 gas adsorption capacity of MoS2 sheets via doping with iron, cobalt, and nickel. We show that substitutional dopants act as active sites for CO2 adsorption. The adsorption performance is determined to be dependent on the type of dopant species as well as its concentration. Nickel-doped MoS2 is found to be the best adsorbent for carbon capture with a relatively high gas adsorption capacity compared to pure MoS2 and iron- and cobalt-doped MoS2. Specifically, Brunauer–Emmett–Teller (BET) measurements show that 8 atom % Ni–MoS2 has the highest surface area (51 m2/g), indicating the highest CO2 uptake relative to the other concentrations and other dopants. Furthermore, we report that doping could lead to different magnetic solutions with changing electronic structures where narrow band gaps and the semimetallic tendency of the substrate are observed and can have an influence on the CO2 adsorption ability of MoS2. Our results provide a key strategy to the characteristic tendencies for designing highly active and optimized MoS2-based adsorbent materials utilizing the least volume of catalysts for CO2 capture and conversion.

Herein, we report a general and straightforward synthesis method for large-pore highly mesoporous metal oxide nanoparticles via a modified inverse micelle formation. The role of diols as solvents has been demonstrated and extended to other metal oxides using ethylene glycol. After scanning most of the metals from the periodic table, magnesium and calcium from the s-block; tin from the p-block; vanadium, nickel, zinc, zirconium, and hafnium from the d-block; and lanthanum and cerium from the f-block elements, all these have been successfully synthesized as large-pore-diameter metal oxides. Because of thermodynamic stability of chelate formation, ethylene glycol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol give a higher pore diameter, whereas a further increase in the diol carbon chain (1,6-hexanediol and 1,12-dodecandiol) leads to pore contraction. By varying the synthesis temperature, the effect of viscosity on the pore diameter has also been demonstrated. Potential applications of oxides of magnesium have been tested for carbon dioxide capture and adsorption of macromolecules such as proteins and lipids and small molecules such as curcumin, dopamine, and sucrose. As predicted, larger-pore-diameter and higher-pore-volume mesoporous magnesium oxide shows higher carbon dioxide capture and adsorption compared to commercial magnesium oxide. A mechanism for the higher pore diameters of mesoporous metal oxide nanomaterials has been proposed based on the results and previous reported literature studies.

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