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Pt/BaO/Al2O3 catalysts with different BaO loadings prepared from Al2O3 nanorods (Pt/BaO/Al2O3-nr) and irregular Al2O3 nanoparticles (Pt/BaO/Al2O3-np) were investigated for NOx storage and reduction (NSR).The Pt/BaO/Al2O3 materials derived from Al2O3 nanorods always exhibited much higher NOx storage capacity (NSC) over the whole temperature range of 100-400℃ than the corresponding Pt/BaO/Al2O3-np samples containing the same BaO loading,giving the maximum NSC value of 966.9 μmol/gcat at 400℃,1.4 times higher than that of Pt/BaO/Al2O3-np.Higher catalytic performance of nanorod-supported NSR samples was also observed during lean-rich cyclic conditions (90 sec vs.5 sec),giving more than 98％ NOx conversion at 300-450℃ over the Pt/BaO/Al2O3-nr sample with 15％ BaO loading.To reveal this dependence on the shape of the support during the NSR process,a series of characterization techniques including the Brunauer-Emmett-Teller (BET) method,X-ray diffraction (XRD),X-ray photoelectron spectroscopy (XPS),H2 temperature programmed reduction (H2-TPR),and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were also conducted.It was found that intimate contact of Ba-Al and Ba-Pt sites was achieved over the Pt/BaO/Al2O3 surface when using Al2O3-nr as a support.This strong interaction among the multi-components of Pt/BaO/Al2O3-nr thus triggered the formation of surface nitrite and nitrate during the lean period,and also accelerated the reverse spillover of ad-NOx species onto the Pt surface,enhancing their reduction and leading to high NSR performance.