Logo
Wydrukuj tę stronę

Nonoparticles materials in diesel particulate filters

The reduction of platinum (Pt) loadings in the catalytic bed constitutes a primary means of reducing cost to the levels required for mass- produced vehicles. We have produced and tested, on the laboratory scale a series of innovative catalysts as an active part of a new PM- filter consisting of Pd-Au-Ag-Ni-Co (non Pt) nanometric, powder alloy.
The hollow part structure of TiO2-x-RuO2-x has been proposed as the active layer on the catalyst support, composed of SiC. We have previously demonstrated that single layers of Pt atoms on some other materials, such as palladium (Pd) or gold- nickel alloys, have higher activities than the analogous all-Pt catalysts. Such control of the composition and structure of the top-most atomic layers of catalyst particles gives hope of achieving the four-fold increase in mass activity catalysts needed to reach automotive catalyst cost targets.
1. INTRODUCTION
The price of the catalyst is one of the main barriers to the development of affordable fuel cells and automotive catalyst bed and DPF.
However, platinum is a very costly noble metal material, and alternatives are needed to reduce the cost for practical application of automotive catalysts and fuel cells.
A very active area of development in the DPF field is optimization of the system.Palladium is a member of the platinum group of metals. It shares many of the chemical properties of platinum. Like platinum, it is used in catalytic converters for cars and for other catalysts that make use of its properties. In short, palladium is a highly useful and highly valued metal.
The role of the surface structure for the catalytic activity of a metal surface is studied using density functional theory. Monatomic steps at close packed Ru and Pd surfaces are identified to be highly reactive for the dissociation of diatomic molecules (NO, CO, N2).
The high reactivity is caused by the existence of a favorable reaction ensemble at which the complex reaction (e.g. stretched NO) coordinates to surface metal atoms [8]. (...)

Artykuł zawiera 12330 znaków.

Źródło: Czasopismo Logistyka

© 2000-2023 Sieć Badawcza Łukasiewicz - Poznański Instytut Technologiczny