While scientists debate whether electric cars are environmental saints or sinners, New Jersey-based Engelhard Corp has invented a catalyst that may turn gas-guzzlers from air-foulers into clean-up machines. Conventional automobile catalysts reduce smog-forming gases such as volatile organic compounds and nitrogen oxides before they leave the tailpipe. The new catalyst, Engelhard's PremAir, destroys 90 per cent of 2 smog components -- ozone and carbon monoxide (CO). The platinum-based catalyst coats the radiator, enabling airflow over itself which converts ozone to oxygen and carbon monoxide to carbon dioxide.