The plasmon-induced heat generation by core–shell Ag0@SiO2 nanoparticle ensemble, i.e., Ag0 nanoparticles coated with a nanometric, amorphous SiO2 layer, has been studied for nanoparticles dispersed in liquid suspensions or deposited in film. Nonmonodispersed, fractal-like Ag0@SiO2 ensembles were synthesized by flame spray pyrolysis, varying Ag0 particle size distribution, and SiO2 shell thickness, ranging from 1 nm up to 5 nm. The particles were characterized by TEM, XRD, XPS, and UV–vis, while the thermoplasmonic heat-generation efficiency was monitored in situ by measuring the temperature rise over the nanoparticle ensembles by an infrared thermal imager under UV–vis irradiation or ambient solar light. We have carried out a systematic investigation of parameters regarding (i) the particle characteristics, (ii) the surrounding medium, and (iii) the irradiation characteristics. The data reveal the determinant role played by the SiO2 shell in the plasmonic heating by Ag0@SiO2. Thus, for the thinner SiO2 coating tailored herein (∼1 nm), under focused solar light, Ag0@SiO2 films were able to produce a significant temperature rise up to T max ∼ 400 °C. The data are analyzed quantitatively within the theoretical frame of Mie theory as extended by Baffou for multiple plasmonic nanoheaters, where we take into account the fractal dimension of the flame-made Ag0@SiO2 ensemble and the occurring collective thermal effects in this geometry. In this context, we interpreted the observed phenomena in terms of the neighboring Ag0–Ag0 coupling within each fractal and the dual role of SiO2 as the dielectric shell medium around the metallic core, as well as the plasmonic separator. Accordingly, we provide a consistent theoretical frame which provides a quantitative hierarchy of the physicochemical parameters, which determine the photoinduced heat generation for realistic nonideal/nonmonodisperse Ag0 ensembles.

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A recyclable Ca-MOF that exchanges Ca2+ by Cu2+ almost quantitatively and quickly was investigated via batch ion-exchange experiments and utilized as a stationary phase in an ion-exchange column for Cu2+ removal from aqueous media.

Copper-cerium mixed oxide catalysts have gained ground over the years in the field of heterogeneous catalysis and especially in CO oxidation reaction due to their remarkable performance. In this study, a series of highly active, atomically dispersed copper-ceria nanocatalysts were synthesized via appropriate tuning of a novel hydrothermal method. Various physicochemical techniques including electron paramagnetic resonance (EPR) spectroscopy, X-ray diffraction (XRD), N2 adsorption, scanning electron microscopy (SEM), Raman spectroscopy, and ultraviolet-visible diffuse reflectance spectroscopy (UV-Vis DRS) were employed in the characterization of the synthesized materials, while all the catalysts were evaluated in the CO oxidation reaction. Moreover, discussion of the employed mechanism during hydrothermal route was provided. The observed catalytic activity in CO oxidation reaction was strongly dependent on the nanostructured morphology, oxygen vacancy concentration, and nature of atomically dispersed Cu2+ clusters.

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The MIL-100­(Fe) metal–organic framework presents a high As­(III) uptake capacity of 120 mg g–1. Mechanistic insights into the role of Fe sites versus carbon sites on As­(III) uptake are provided by a comparative study of a series of MIL-100­(Fe) calcinated at 600, 800, and 900 °C. Using powder X-ray diffraction, TEM, scanning electron microscopy, and N2-porosimetry, we have mapped the morphology evolution of the materials. Fourier transform infrared spectroscopy, thermogravimetric analysis, and electron paramagnetic resonance show that noncalcined MIL-100­(Fe) bears Fe3+ atoms; however, after carbonization, a porous carbon matrix is formed bearing zero-valent iron cores coated with an Fe-oxide layer and iron carbide. The relative proportion of these phases depends on the calcination temperature, that is, 600, 800, and 900 °C. A comprehensive surface complexation model is presented, allowing a quantitative description of the As­(III) adsorption on Fe sites and carbon sites. More specifically, As­(III) uptake can be attributed to specific FeOH sites, located inside the pores and carbon C x OH2 sites located on the surface. Confinement inside the pores is found to be responsible for the lateral interactions among the adsorbed [H3AsO3] species. The As­(III) uptake of MIL-100­(Fe) is 3- to 10-fold higher versus pertinent adsorbent materials, such as graphite/graphite oxide, activated carbon, and pyrolytic carbon, and comparable with that of MIL-101­(Cr).