title: Structure of BaO on hierarchical macro-meso-microporous alumina and its effect of interaction with Pt nanoparticle on NO2 desorption.
abstract: Recently, the lean NOx trap technology using supported Pt catalyst on alumina was devised to store NOx under lean condition and to reduce into N2 and water under rich condition in lean burn engine. In this work, the effect of the Pt nanoparticle supported on hierarchical macro-meso-microporous BaO-Al2O3 on NO2 desorption has been investigated with NO2 temperature programmed desorption, TEM, SEM, TGA and hydrogen chemisorption. Crystalline BaO phase of 20-30 nm thickness were obtained on the hierarchical macro-meso-microporous Al2O3 with a simple impregnation of Ba(NO3)2 and Ba(ClO4)2. The interaction of Pt and BaO was resulted in the formation of atomically dispersed Pt nanoparticles and also decreased the desorption temperature of NO2 adsorbed on BaO at much lower temperature than that from the BaO-Al2O3 support only. This synergistic lowering of NO2 desorption temperature may be originated from the interaction between Pt and BaO.
authors: Clean Energy Technology Laboratory and Department of Applied Chemical Engineering, Chonnam National University, Gwangju 500-757, Korea.
authors: Ik Jun
authors: IJ
authors: Jang
authors: Hye Sun
authors: HS
authors: Shin
authors: Na Ra
authors: NR
authors: Shin
authors: Su Hyun
authors: SH
authors: Kim
authors: Sung June
authors: SJ
authors: Cho