Easy hydrothermal synthesis of external mesoporous γ-Al2O3 nanorods as excellent supports for Au nanoparticles in CO oxidation

External mesoporous gamma-Al2O3 nanorods with an aspect ratio of 2-4 has been hydrothermally synthesized using Al(NO3)(3)center dot 9H(2)O as precursor and (NH4)(2)CO3 as precipitant without any templates and followed by a calcination step. The obtained samples were characterized by thermogravimetric analysis (TG), X-ray powder diffraction (XRD), nitrogen sorption, Fourier transform infrared spectrometry (FT-IR), and scanning transmission electron microscopy (STEM). It can be confirmed that the morphology of nanorods is formed in the low-temperature hydrothermal process of 100 degrees C. Through the thermal decomposition of intermediate product NH4Al(OH)(2)CO3, the prepared gamma-Al2O3 possesses abundant external mesopores, which can act as holders to stabilize or anchor gold nanoparticles efficiently. Using CO oxidation as an probe reaction, the results demonstrated that Au catalyst exhibited excellent catalytic performance with the complete CO conversion at 18 degrees C (T-50% = -11.2 degrees C) and reactive stability over 166 h under a space rate of 134,000 mL h(-1) g(cat)(-1). (c) 2013 Elsevier Inc. All rights reserved.