imp prepared via a traditional impregnation method was used for comparison. The promotion effect of modifiers on the physicochemical properties and catalytic performance of the catalysts was systematically investigated. Characterization and evaluation results indicated that the modified catalysts showed higher activities and better coking-resistance than Ni/g-Al 2 O 3 , and Ni/La 2 O 3 -g-Al 2 O 3 was found to be the most effective one. All the catalysts with or without modifiers presented similar Ni particle sizes due to the enhanced metal-support interaction derived from the reduction of the NiAl 2 O 4 precursor. However, more medium-strength basic sites on the catalyst surface were obtained by adding promoters, which could facilitate the adsorption/activation of CO 2 and the gasification of amorphous carbon, improving the catalytic properties and accelerating the coke elimination rate. Additionally, the incorporation of promoters also prevented the phase transformation of g-alumina.and prevent the sintering of active sites and supports. [32][33][34][35][36][37] Therefore, in pioneer literatures, lots of oxides, especially MgO, 7 CaO, 30 La 2 O 3 , 38 and CeO 2 , 39 have been used as promoters to improve the catalytic properties and reduce coke deposition. Recently, many new methods were developed to add the promoters. Ma et al. 38 prepared the La-modied ordered mesoporous Ni-based catalysts via a one-pot evaporation induced self-assembly method. Ni/SiO 2 doped with La 2 O 3 catalysts were synthesized through an in situ self-assembled core-shell precursor route and used for dry reforming of methane. 40 Catalyst-supports, 10 mol% X-ZrO 2 (X ¼ La, Ce, Pr, Nd, Y) were prepared using a complex polymerized method, and catalyst of 1 wt% Ni/10 mol% La-ZrO 2 showed very high DRM activity. 41 In our previous study, mesoporous crystalline g-aluminas with excellent textural properties and thermal and hydrothermal stability were synthesized via the one-pot partial hydrolysis of Al(NO 3 ) 3 aqueous solution with (NH 4 ) 2 CO 3 , 42 and based on this result, mesoporous NiAl 2 O 4 /g-Al 2 O 3 nanocomposites with high specic surface areas, large pore volumes and narrow pore size distributions were also successfully prepared and showed excellent catalytic performance for DRM aer H 2 reduction. 43 The mesoporous spinel structure could effectively stabilize the metallic Ni during the process of in situ reduction and DRM reaction at high temperatures. Therefore, in order to develop more efficient Ni-based catalysts, we intend to systematically investigate the inuence of different chemical environments and electronic effects caused by doping La, Ce, Ca, and Mg promoters on the catalytic performance of the catalysts for DRM reaction.Herein, mesoporous NiAl 2 O 4 /g-Al 2 O 3 and NiAl 2 O 4 /MO x (M ¼ La, Ce, Ca, Mg)-g-Al 2 O 3 materials were successfully synthesized through the facile one-pot partial hydrolysis of metal nitrates aqueous solution with (NH 4 ) 2 CO 3 . Without any surfactants that makes the prepared procedure to be...