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Accelerated aging of automotive catalysts has become a routine process for the development of new catalytic formulations and for homologation of vehicle emissions. In the standard approach, catalyst samples are subjected to temperatures in excess of 800°C on a predefined test cycle and aged for precise timescales representative of certain vehicle mileage. The high temperature feed gas is traditionally provided by a large gasoline engine but, increasingly, alternative bench-aging techniques are being applied as these offer more precise control and considerable cost savings, as well as offering more development possibilities. In the past few years, emissions control of light duty vehicles has become increasingly prominent as more stringent emissions legislations require more complex after-treatment systems. Aging of the catalysts are not fully understood as they are subjected to many varying environments, including temperature and gas concentrations.

A three-way automotive catalyst's ability to store oxygen is still a crucial performance metric for modern day catalyst applications. With more stringent emissions legalisation, the oxygen storage capacity (OSC) within a catalyst can assist with converting different harmful exhaust gases such as CO, THC and NOx under transient operating conditions. Additionally, OSC is currently the only onboard catalyst performance metric recorded during a vehicle's useful life. Catalyst performance is correlated to this OSC measurement. OSC in three-way automotive catalysts can be split into two main OSC types. "Latent" OSC deep within the washcoat and "dynamic" OSC on the surface of the catalyst washcoat. Dynamic OSC is more commonly applied in the evaluation of useful OSC of the catalyst during practical operation.