Selective Hydrogenation of Cinnamaldehyde over Co-Based Intermetallic Compounds Derived from Layered Double Hydroxides
Selective hydrogenation of unsaturated carbonyl compounds plays a key role in the production of fine chemicals and pharmaceutical agents. In this work, two kinds of intermetallic compounds (IMCs: CoIn3 and CoGa3) were prepared via structural topotactic transformation from layered double hydroxide (L...
Gespeichert in:
Veröffentlicht in: | ACS catalysis 2018-12, Vol.8 (12), p.11749-11760 |
---|---|
Hauptverfasser: | , , , , , , |
Format: | Artikel |
Sprache: | eng |
Online-Zugang: | Volltext |
Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
Zusammenfassung: | Selective hydrogenation of unsaturated carbonyl compounds plays a key role in the production of fine chemicals and pharmaceutical agents. In this work, two kinds of intermetallic compounds (IMCs: CoIn3 and CoGa3) were prepared via structural topotactic transformation from layered double hydroxide (LDH) precursors, which exhibited surprisingly high catalytic activity and selectivity toward hydrogenation reaction of α,β-unsaturated aldehydes (CO vs CC). Notably, the CoGa3 catalyst shows a hydrogenation selectivity of 96% from cinnamaldehyde (CAL) to cinnamyl alcohol (COL), significantly higher than CoIn3 (80%) and monometallic Co catalyst (42%). A combination study including XANES, XPS, and CO-IR spectra verifies electron transfer from Ga (or In) to Co, leading to the formation of CoGa (or CoIn) coordination. FT-IR measurements and DFT calculation studies substantiate that the electropositive element (Ga or In) in IMCs serves as an active site and facilitates the adsorption of polarized CO, while CC adsorption on the Co site is extremely depressed, which is responsible for the markedly enhanced selectivity toward hydrogenation of CO. This work reveals the key role of functional group adsorption in determining the hydrogenation selectivity of α,β-unsaturated aldehydes, which gives an in-depth understanding on the structure–property correlation and reaction mechanism. |
---|---|
ISSN: | 2155-5435 2155-5435 |
DOI: | 10.1021/acscatal.8b02755 |