Semi-hydrogenation of α,β-unsaturated aldehydes over sandwich-structured nanocatalysts prepared by phase transformation of thin-film Al2O3 to Al-TCPP

Bin Chen; Xin Yang; Yinan Xu; Siyuan Hu; Xiaoli Zeng; Yiping Liu; Kok Bing Tan; Jiale Huang; Guowu Zhan

doi:10.1039/d2nr04474a

Semi-hydrogenation of α,β-unsaturated aldehydes over sandwich-structured nanocatalysts prepared by phase transformation of thin-film Al₂O₃ to Al-TCPP

Nanoscale. 2022 Nov 3;14(42):15749-15759. doi: 10.1039/d2nr04474a.

Authors

Bin Chen^{1

2}, Xin Yang¹, Yinan Xu³, Siyuan Hu¹, Xiaoli Zeng¹, Yiping Liu¹, Kok Bing Tan², Jiale Huang², Guowu Zhan¹

Affiliations

¹ College of Chemical Engineering, Integrated Nanocatalysts Institute (INCI), Huaqiao University, 668 Jimei Blvd., Xiamen, Fujian, 361021, P. R. China. gwzhan@hqu.edu.cn.
² Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, 422 Siming South Road, Xiamen, Fujian 361005, P. R. China. cola@xmu.edu.cn.
³ Davidson School of Chemical Engineering, Purdue University, 480 Stadium Mall Drive, West Lafayette, IN 47907, USA.

PMID: 36226736
DOI: 10.1039/d2nr04474a

Abstract

The semi-hydrogenation of α,β-unsaturated aldehydes to the desired unsaturated alcohols with both high conversion and high selectivity remains a big challenge. Herein, we designed a sandwich-structured nanocatalyst for the highly selective hydrogenation of various α,β-unsaturated aldehydes (e.g., cinnamaldehyde, furfural, crotonaldehyde, and 3-methyl-2-butenal) to the targeted unsaturated alcohols. Highly accessible platinum nanoparticles were sandwiched between a metal-organic framework (MOF) core (i.e., MIL-88B(Fe)) and a MOF shell (i.e., Al-TCPP). In particular, the growth of the Al-TCPP shell was achieved by atomic layer deposition (ALD) of thin-film Al₂O₃ followed by phase transformation with a tetrakis(4-carboxyphenyl)porphyrin (H₄TCPP) linker. The thickness of the Al-TCPP shell can be finely controlled by adjusting the cycle number of alumina ALD and the concentration of the H₄TCPP linker during the phase transformation of Al₂O₃ to Al-TCPP. It was proven that the permeable MOF shells could serve as selectivity regulators for the activation of the CO bonds in α,β-unsaturated aldehydes (in preference to the CC bonds), leading to higher selectivity towards unsaturated alcohols as compared to the conventional surface supported Pt catalysts. Mechanistic insights showed that the enhanced catalytic performance was attributed to (i) the modified electronic state of sandwiched Pt nanoparticles by the two MOF layers and (ii) the steric hindrance effect on substrate diffusion through the sandwich-structured catalysts.