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Low-temperature activity is an important requirement for automotive catalysts. In particular, most of the tailpipe emissions occur right after the engine starts (cold emissions). These emissions can be effectively reduced by using a trap material such as zeolite for hydrocarbon (HC) adsorption [1, 2, 3, 4, 5, 6, 7, 8, 9]. However, using zeolite as a trap material in automotive catalyst is limited due to its low durability under hydrothermal aging conditions. That is the reason why zeolites can be often used for diesel engines which usually run at lower temperature than the gasoline engines during entire mode driving. In most cases, zeolites need to be placed away from large thermal loads in order to take advantage of their adsorption abilities. In general, the thermal endurance of close-coupled catalysts for gasoline powered vehicles proceeds at about 1000 °C in the presence of water.