Nanocasted oxides for oxidative dehydrogenation of ethylbenzene utilizing CO2 as soft oxidant

Styrene Oxidation to Valuable Compounds over Nanosized FeCo-Based Catalysts: Effect of the Third Metal Addition

“…Indeed, the surface of the sphere observed for FCM NC was almost broken and irregular with core permeated through the spheres walls (Figure 1c included on the left). This implies that the metal precursors penetrated into the core of the hollow spheres, and the subsequent thermal degradation contributed to the sintering process, in accordance with a previous work [20].…”

“…In other words, the Type IV isotherms with H 1 hysteresis are clearly observed for all synthesized samples, except for FCC CP and FCM CP having a Type I isotherm. Interestingly, FCC SG does not have a well-defined Type IV pattern, and this behavior corresponds to those of mesopores and macropores presence [20,21], as already suggested by SEM (Figure 1c included). Additionally, the hysteresis loop for the FCC SG is not well established, presumably because of the presence of inter-particle void space.…”

“…However, the interesting phenomenon is that no diffraction peaks appear for the solids synthesized via the nanocasting (NC) route, being amorphous in nature. This is an indication that the dispersion of the species on the surface or pores is favored [20,23]. Thus, detailed inspection on the magnified peaks suggests that some oxide reflections emerged (shown in the figure included at the right side of Figure 3).…”

“…This nanoarchitecture is duly reflected by the XAD-16 resin template hollow sphere morphology [20,21]. Some of the spheres were unbroken, indicating that the metal precursors infiltrated successfully into the spheres, whilst other spheroids were cracked because the calcination process burned the template (Figure 1a included, left side).…”

“…These results might be due to the CP method as a variant of sol-gel method, providing the interactions among the depolimerized P-123 copolymer, hydrochloric acid, citric acid, and the metal precursors. It can provide an anisotropic aggregation of thermodynamically unstable metal-oxo-metal or metal-hydroxy-metal species, all of them giving a void space of self-assembled micellar, as for Fe-based compounds [20,21]. In addition, the sol-gel involved reactions are occurring simultaneously during the aging step [21].…”