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Super-microporous alumina (pore size between 1 and 2 nm) with polycrystalline walls and high surface area (more than 650 m 2 /g) was synthesized successfully via an evaporation induced self-assembly (EISA) pathway using readily available and inexpensive nonionic surfactant fatty alcohol polyoxyethylene ether (AEO-7) as the template. N 2 adsorption-desorption results showed that the obtained materials are super-microporous when removing the template at 400 °C, then if the calcination temperature increase from 600 °C to 1000 °C, a breakdown of the walls separating adjacent pores allows the transformation to mesopores (pore size > 2 nm). FTIR pyridine adsorption and NH 3 -TPD measurement suggested the presence of strong Lewis acid sites. Transmission electron microscopy (TEM) measurements indicated that the alumina possesses the disordered “wormhole-like” super-microporous structure with polycrystalline walls. Loaded with copper, the catalyst exhibited outstanding activity in the selective catalytic reduction of NO with methane and could achieve a NO x conversion 100% when the reaction temperature is over 600 °C. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Micro-mesoporous alumina-zirconia nanocrystals are prepared by vapor-induced route. • The Al incorporation improves the textural properties of the composites. • The largest surface area of 313 m2/g is obtained. • The samples possess stable tetragonal structure of zirconia. • The samples show large pore volumes in the range of 0.18–0.39 cm3/g. Abstract Micro-mesoporous alumina-zirconia nanocrystals with controllable textural properties are prepared using triblock copolymer F127 as a template via one-pot vapor-induced pathway. The BET surface area and pore volume of the samples increase with rising aluminum content. When the Al/Zr molar ratio is 0.6, the sample exhibits highest surface area of 313 m2/g of which 118 m2/g in the form of micropores after high temperature calcination. Moreover, the incorporation of Al species enhances the structural stability of zirconia in tetragonal phase. [ABSTRACT FROM AUTHOR]