In situ encapsulated Co/MnOx nanoparticles inside quasi-MOF-74 for the higher alcohols synthesis from syngas

In Situ Encapsulated CuCo@M-SiO2 for Higher Alcohol Synthesis from Biomass-Derived Syngas

“…Several reaction intermediates were identified, including CH 2 */CH 3 *, HCOO*, and OH* species. As shown in Figure , the peaks at 2105 and 2171 cm –1 could be ascribed to the gaseous CO in the feedstock. − The peak at 1870 cm –1 was assigned to the bridge-type-adsorbed CO on Co-active sites . To further verify the CO bridge-type and linear adsorption with different active interfaces, in situ CO-DRIFTS was adopted.…”

“…To further verify the CO bridge-type and linear adsorption with different active interfaces, in situ CO-DRIFTS was adopted. As shown in Figure S16, the adsorption band at 1868 cm –1 could be assigned to the CO adsorbed on Co 0 in bridging geometry adsorption, while the band at 2119 cm –1 should be attributed to the CO linearly adsorbed on Co n + . ,, Moreover, the adsorption peak at 2172 cm –1 was due to the CO linearly bonded with the Cu species. − Furthermore, as exhibited in Figure , the peaks at 2943 and 1456 cm –1 were attributed to the C–H bending δ­(CH) and C–H symmetric stretching n s (CH) of CH 2 */CH 3 * species. − However, the bands at 1365 and 1068 cm –1 were ascribed to δ­(CH 3 ) and ρ­(CH 3 ). , The bands at 1401 and 1588 cm –1 corresponded to n s (OCO) and asymmetric stretching n as (OCO) of the HCOO* species. , The peak at 3740 cm –1 assigned to OH-stretch vibrations, indicating the existence of alcohols or water species on the catalysts during the reaction. The peaks at 2335 and 2362 cm –1 were attributed to the gaseous adsorbed CO 2 …”

“…In addition, new visible peaks appeared at 500–700 cm –1 , which would be attributed to the Cu–O or Co–O stretching vibration peak, suggesting the presence of CuO x or CoO x in CuCo@M-SiO 2 -W and CuCo@M-SiO 2 -E. Those results were also further demonstrated by FT-IR (Figure S4b). The observable peak of FT-IR at 1175 cm –1 was assigned to ν (CC) of the carbon. , In contrast, it was not found in the ν (CC) of the carbon in all precursors (Figure S4a).…”

“…However, CO* reacted with OH* to generate HCOO* intermediates, subsequently hydrogenated to form CH x O* species. In addition, CH x O* species were inserted into these alkyl chain C x H y * species to obtain C x H y CHO* species and further hydrogenated to C 2+ OH . In short, synergetic catalysis of Co 0 and Cu 0 /Co n + with close vicinity was responsible for the synthesis of higher alcohols over the CuCo@M-SiO 2 catalyst.…”

“…Higher alcohols (HAs or C 2+ OH) are an effective alternative energy to petroleum fuels and have been in the spotlight for valorization as value-added chemicals, pharmaceuticals, plasticizers, lubricants, and detergents. Especially, they are environmental friendly clean gasoline blends with increased octane number, thus improving the engine performance. − In recent years, HA synthesis (HAS) from biomass-derived syngas is a cutting-edge process for its underlying application in the sustainable carbon cycle. − Also, syngas can be derived from coal, natural gas, and/or shale gas. However, it is an enormous challenge to achieve a trade-off between the C–C coupling and the C–O retaining.…”