Super Intelligent Catalyst
The "intelligent catalyst" used on Daihatsu vehicles is an innovative technology. We have given a self-regenerating function to palladium (Pb), a precious metal used in automotive catalysts, to prevent its exhaust gas cleansing function from deteriorating over time. Our research results were introduced in England's most authoritative science magazine, Nature (11th July, 2002 issue). We have also received many awards for this achievement. At the present, the intelligent catalyst is being used in several of Daihatsu's production models.
Automotive Catalyst Functions
We have also further advanced this technology and developed the "super intelligent catalyst," in which all three precious metals — palladium (Pd), rhodium (Rh) and platinum (Pt) — have gained a self-regenerating function. The new technology further reduces the consumption of precious metals to conserve valuable natural resources, and achieves cleaner emissions at the same time. It is a technology with the potential to become the global standard in the automotive industry.
Exhaust gases produced and emitted by petrol-engine automobiles contain hazardous substances (carbon monoxide, hydrocarbon, nitrogen oxides, etc.). To prevent these harmful substances from being released directly into the atmosphere, automobiles are equipped with a component called a catalyst for purifying the exhaust gas through chemical reactions.
catalyst purifying performance vs.travel distance
These chemical reactions take place on the micro-particle surfaces of precious metals, such as palladium and platinum. The finer the metal particles are, the larger the surface area of the metal exposed to the exhaust gas becomes, thus increasing the cleansing effect. The catalyst is installed right under the engine and exposed to the extremely hot exhaust gas that leaves the engine. Exhaust gas temperatures can be as high as 1,000°C under some operating conditions. Since precious metals such as palladium are vulnerable to high temperatures, their micro-particles bond with adjacent micro-particles due to high heat and grow precious particles into a huge lump. As a result, their purifying performance drops over years of use.
In anticipation of this deterioration of catalyzing performance that occurs over time, catalysts are produced with increased amounts of precious metals. As emission regulations are becoming stricter, the consumption of precious metals has increased all over the world. Those precious metals are also used in a wide range of applications in the electronics and chemistry fields, for example, in dentistry and other areas. Because precious metals are valuable and in limited supply, there is a strong need to reduce their consumption for automotive applications.
Comparison of precious metal conditions in vehicle lifetime
To respond to this need, Daihatsu actively conducted research aimed at discovering a method to "prevent phenomenon known as particle growth" with the cooperation of research organizations such as the Japan Atomic Energy Agency. To that end, Daihatsu has developed a nano-technology that precious metal ions, at the atomic level, into ceramic crystals. According to the conventional knowledge for catalysts, this method was believed to be ineffective for preventing deterioration of catalyzing performance. However, an intriguing phenomenon occurred. Together with the cyclic change in exhaust gas components, the precious metal ions entered and exited the ceramic crystals repeatedly as if they had intelligence, and the precious metal ions did not grow larger in size.
This "self-regenerating" function has enabled the retention of the initial catalyzing performance and allowed a significant reduction in the consumption of all three valuable and rare precious metals — palladium, rhodium and platinum.
Perovskite-type crystal