Synergistic effect of hematite facet and Pd nanocluster for enhanced acetylene dicarbonylation

In this work, the influence of the hematite morphology on the dicarbonylation of acetylene is investigated in detail. The Pd/α-Fe2O3 catalysts perform a significant support-morphology-dependent catalytic performance, which could be correlated to the exposed crystal planes and surface composition of the α-Fe2O3 nanocrystals. [Display omitted] •A strong morphology effect of α-Fe2O3 on Pd/α-Fe2O3 for the acetylene dicarbonylation has been systematically studied.•The Pd/HNRs (110) catalyst endows its highest Pd-Fe2O3 interaction and then decrease the CO adsorption strength.•More moderately acidic sites on HNRs (110) crystal plane could facilitate C2H2 activation.•Excellent catalytic performance could be attributed to the synergistic effect of palladium and α-Fe2O3 support.•The Pd/HNRs catalyst being used in up to eight consecutive cycles without loss of activity or selectivity significantly. It is very challenging to improve the catalytic activity of Pd-based catalysts since the strong CO chemisorbtion on Pd leading to poor activity at ambient temperature. Herein, we report that modulating the exposed facet of α-Fe2O3 nanocrystalline, i.e. (110), (001) and (012), is a facial way to improve catalytic activity for acetylene dicarbonylation. The obtained Pd/HNRs catalyst with exposed (110) crystal plane give a 100 % acelyene conversion at room temperature. Through a combination of X-ray photoelectron spectroscopy and H2-TPR, we demonstrate that the Pd-HNRs interaction leads to the weaker CO absorption strength. Meanwhile, the kinetics studies demonstrate that α-Fe2O3 oxide extends the reaction routine due the improved activity of C2H2, with the help of moderately acidic sites, then overcome the inhibition of the C2H2 activating in pure Pd species. Moreover, we verified a satisfying reusability over the Pd/HNRs catalyst, being used in up to eight consecutive cycles without loss of activity or selectivity significantly.