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This paper describes the development of a novel low precious metal nano-technology catalyst (Nanocat) and its application in a modern European gasoline vehicle. Three iterations of low precious metal nano-technology catalysts were tested on a Euro 3 certified gasoline vehicle over the European drive cycle (EDC). Engine dynamometer lean spike ageing was used to simulate aged catalysts representing approximately 100 000 km on-road ageing. The fresh and aged nano-technology catalysts were tested and compared to the vehicle production catalyst. The third iteration of fresh nano-technology catalyst met Euro 3 emissions legislation and also met Euro 4 limits for HC and NOx. However, after lean spike ageing the NOx levels exceeded Euro 3 limits but the HC tailpipe remained within Euro 4 limits. The ageing process caused an 18% reduction in the NOx conversion but the HC conversion was maintained.

A ceria stabilised zirconia supported Pd/Zn catalyst (Pd/Zn ratio=1:2) has demonstrated its ability to perform as a three-way catalyst (TWC) and to give conversions of up to 99% of a stoichiometric mixture of carbon monoxide/npropane/nitric oxide/dioxygen in dinitrogen carrier at a WHSV of 44,000 h-1. The catalyst also exhibits excellent thermal stability inoxidising conditions. Characterisation of the catalyst has been performed using XRD, XPS, BET,and DSC. From this it has emerged that the palladium is in a highly dispersed state, closely associated with the zinc phase. In situ kinetic studies have also been conducted under continuous flow conditions.