Measurement of intrinsic catalytic activity of Pt monometallic and Pt-MoOx interfacial sites over visible light enhanced PtMoOx/SiO2 catalyst in reverse water gas shift reaction

作者：Ro Insoo; Sener Canan; Stadelman Thomas M; Ball Madelyn R; Venegas Juan M; Burt Samuel P; Hermans Ive; Dumesic James A; Huber George W

来源：Journal of Catalysis, 2016, 344: 784-794.

DOI：10.1016/j.jcat.2016.08.011

• Bimetallic catalyst
• Monometallic sites
• Interfacial sites
• Photocatalysis
• Visible light response
• Active sites
• Reverse water gas shift (RWGS) reaction

Supported Pt-Mo catalysts were prepared with different Mo contents by a controlled surface reaction (CSR) method and studied for the reverse water gas shift (RWGS) reaction under dark and visible light irradiation conditions. Characterization results from Raman spectroscopy, scanning transmission electron microscopy (STEM), CO chemisorption, and inductively coupled plasma-absorption emission spectroscopy (ICP-AES) indicate that selective Mo deposition onto Pt was achieved at low Mo loading (Mo/Pt ratio < 0.3). Mo deposition changed the apparent activation energy and CO2 and CO reaction orders. Visible light irradiation changed the apparent activation energy and reaction orders of CO2, CO, and H-2, ascribed to direct photoexcitation. The intrinsic activity of a Pt site is 0.4 and 4.1 mint under dark and light conditions at 473 K, respectively, whereas the intrinsic activity of a Pt-MoOx site is increased to 22.7 and 160 min(-1) under dark and light conditions at 473 K, respectively.

• 出版日期2016-12