Thai Noipho/iStock via Getty Images Co-authored by Treading Softly. When you hear the word catalyst, what comes to mind? For many, you may immediately think of your car and its catalytic converter. Good thinking! The catalytic converter contains a material to help finalize the conversion of emissions in your car's exhaust system to less dangerous and less smelly gases. A catalyst is something, a chemical, a material, or an energy source that helps kickstart a reaction and often remains unchanged by the reac ...