Mazda Motor will fit the world’s first single-nanocatalyst to its redesigned 3 (sold as the Axela in Japan) on sale later this year. The new catalyst, said to be highly durable, significantly reduces the amount of precious metals used.
With the single-nanocatalyst, the underfloor catalytic converter requires only 0.15g/l of precious metals, approximately 70% less than the 0.55g/l required in the previous model. Along with the substantial reduction in precious metal usage, the Axela continues to qualify as a super ultra-low emissions Vehicle (SU-LEV) in Japan by achieving exhaust emissions that are at least 75% cleaner than the government’s 2005 regulations.
In conventional catalysts, exposure to hot exhaust gases causes the precious metal particles to agglomerate into larger clumps, which reduces their effective surface area and catalytic activity. To counteract this, an increased amount of the precious metals is required to maintain an efficient purification performance.
The single-nanocatalyst increases the effective surface area of the precious metals used. By developing a method of controlling precious metal particles that are less than five nanometres (nm) in diameter as well as a proprietary catalyst material structure, the automaker achieved the first catalyst to have single-nanosized precious metal particles embedded in fixed positions. As a result, there is no agglomeration of the particles and the amount of rare metals used can be significantly reduced.
The new catalyst material will also enable very efficient purification with minimal deterioration over time even under the harshest operating conditions, the automaker claimed.
Mazda said it would introduce the single-nanocatalyst in all markets.