Porous TiO2/Pt/TiO2 Sandwich Catalyst for Highly Selective Semihydrogenation of Alkyne to Olefin

• Published in: ACS catalysis Vol. 7; no. 10; pp. 6567 - 6572
• Main Authors: Liang, Haojie, Zhang, Bin, Ge, Huibin, Gu, Xiaomin, Zhang, Shufang, Qin, Yong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 06.10.2017
• Subjects: atomic layer deposition; sandwich structure; metal−oxide interface; tandem catalyst; semihydrogenation
• ISSN: 2155-5435; 2155-5435
• DOI: 10.1021/acscatal.7b02032

The tailoring of metal–oxide interfaces is a powerful approach to enhance the catalytic efficiency of heterogeneous catalysts. However, the function of the metal–oxide interface is still not clearly understood in most catalytic processes. The construction of heterogeneous catalysts with single interface sites would be a straightforward way to reveal the interface effect. In this work, we introduced a simple strategy to synthesize a porous TiO2/Pt/TiO2 sandwich catalyst by atomic layer deposition. All Pt nanoparticles were covered by two porous TiO2 layers in this sandwich structure, creating dominant Pt–TiO2 interface sites. The TiO2/Pt/TiO2 sandwich catalyst shows good catalytic performance in the tandem ammonia–borane decomposition and semihydrogenation of various alkynes with high selectivity and stability. In contrast, the Pt nanoparticles without complete coverage of porous TiO2 layers have a low selectivity in semihydrogenation of alkynes. The sandwich catalyst also exhibits high selectivity in hydrogenation of the −CO bond of α,β-unsaturated aldehyde. The high selectivity of the TiO2/Pt/TiO2 sandwich catalyst can be ascribed to the electron-rich property of the Pt–TiO2 interface sites, which favor the adsorption of alkyne with electrophilicity but inhibit the overhydrogenation of CC bonds.