Morphological changes of Pt nanocrystals under oxidation environment

Abstract

Pt nanocrystals are used in a various application such as hydrogen fuel cell, catalysis for carbon monoxide oxidation, etc. Especially Pt surface oxides play an important role in catalyst performance. To analyze nanocrystals surface oxidation, we investigated x-ray crystal truncation rod (CTR) under oxidation conditions. X-ray CTR is caused by the cutting plane of the crystals. By observing change of x-ray CTR, we can present morphological evolution of Pt nanocraystals oxidation process. In order to practical x-ray diffraction analysis, we require to fabricate mono-disperse axis aligned periodic Pt nanocrystals array. Such Pt nanocrystals array are effective for understand the average crystal properties through statistical methods. We employed a mask-deposition, thermal annealing method to fabricate particular Pt nanocrystals array. Pt nanocrystal array quality is determined using SEM image analysis. In this work we fabricated mono-disperse Pt nanocrytals array and monitored x-ray diffraction CTR. Our finding describes average morphological evolution of Pt nanocrystals array during oxidation process. Thus, identifying the average character of Pt nanocrystals will contribute to the commercialization of effective Pt nanocrystals in an economical and easy way.