X-type zeolite with mesoporosity (Meso-13X) was prepared by using dimethyloctadecyl[3- trimethoxysilyl) propyl] ammonium chloride as a mesopore-generating agent, and then modified with polyethylenimine (PEI) through a physical impregnation method to form a hybrid material (Meso-13X- PEI). Meso-13X with and without PEI was characterized by X-ray powder diffraction (XRD), N-2 adsorption-desorption isotherm at 77 K, scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Meso-13X-PEI exhibited higher CO(2)capture capacity than PEI-modified zeolite 13X owing to its larger pore volume that accommodates more amine species inside the pore structure, and the mesoporosity also can facilitate dispersion of PEI molecules inside the pore channels. Compared to zeolite 13X, Meso-13X-PEI showed much higher CO(2)capture selectivity (against N-2) as well as higher CO(2)capture capacity at relatively high temperature (e.g. 100 degrees C) and dilute CO2 concentration relevant to post-combustion conditions. (C) 2015 Elsevier B.V. All rights reserved.