![]() ![]() The catalytic performance of these structures depends to a great extent on the material composition and design, offering an improved nanoarchitecture resulting from the synergy that can be promoted between the core and shell or from the combination of the properties of the structural components. CSNs consist of a core enveloped by one or more layers, in other words, a multifunctional system integrated into a single unit. Core-shell nanoparticles (CSNs) stand out among nanostructured materials because of their great impact on catalysis. Nanotechnology is a multidisciplinary field that has brought great advances in different areas such as medicine, biology, electronics, and catalysis. Finally, the most selective systems were tested for operational stability, where the Fe 2O catalyst could be reused in three consecutive operating cycles while maintaining its activity and selectivity for cinnamyl alcohol – unlike the Fe 2O 2-5%Pt reduced system, which was deactivated after the third reaction cycle due to active phase leaching. However, the reduced Fe 2O 2-5%Pt system showed 98 % conversion with 95 % selectivity for cinnamyl alcohol at 24 h of operation the increase in selectivity is attributed to the combined effects of the increase in average particle size (~7.5 nm) and the presence of strong metal-support interaction – SMSI – effects after reduction. After reduction in H 2 at 773 K, the Fe 2O 2-1%Pt catalyst showed deactivation, reaching 10 % conversion at 600 min of reaction and 60 % selectivity for the product of interest. However, the Fe 2O 2-x%Pt systems showed lower levels of conversion and selectivity compared to those of the Fe 2O 2-x%Pt catalysts, which is attributed to the fact that average metal particle sizes below 5.0 nm were obtained in both cases. The particle size effect enabled the Fe 2O 2-5%Pt system, with an average particle size of 5.6 nm, to reach 100 % conversion of cinnamaldehyde at 300 min of reaction, producing cinnamyl alcohol with 90 % selectivity this result differed greatly from that of the Fe 2O 2-1%Pt (d Pt = 3.5 nm) system, which reached a maximum conversion at 600 min with 49 % selectivity for the product of interest. Moreover, the effect of particle size on the selective production of cinnamyl alcohol was studied by preparing two families of catalysts with metal loadings of 1 wt% and 5 wt% Pt with respect to the core-shell. ![]() At the same time, this study details the effect of the shell on the catalytic performance. The structures were designed with a magnetic core so they could be easily recovered from the catalytic bed by simple magnetization and with a SiO 2 monoshell or a SiO 2 multishell to protect the magnetic core. Commissioning has not yet been completed, and there is no electrical service to the building at this time, but equipment has already been installed.This study reports the catalytic preparation, characterization, and evaluation of nanoscale core-shell structures with a γ-Fe 2O 3 core covered by a SiO 2 monoshell or by a SiO 2 multishell as a support for Pt nanoparticles (NPs) to synthesize active and operationally stable catalysts for selective liquid-phase cinnamaldehyde hydrogenation. The square footage of the office portion exceeds 60% of the total building area. The building has upgraded all of its electrical, plumbing and mechanical infrastructure serving the office floors. For example, the 4th floor was a spec suite that is being built our seperately, all other floors are being built out as cold shells with HVAC capped at each floor. The upper floors, all office, seperately managed, are included in the scope of the consutruction, but under seperate permits for seperate phases of the development. ![]() The 1st floor and Mezzanine are not part of the renovation are both already occupied and operated as retail spaces. We have a building undergoing a major renovation that is retroactively seeking LEED Core & Shell v4.1. ![]()
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