Johnson Matthey, the autocatalyst maker and precious metal refiner, has seen a sharp fall in sales of catalytic converters over the past three months due to the slowdown in the car industry, although continued interest in alternative energy has buoyed demand for its environmental technologies.

The company, which is the world’s largest maker of catalytic converters, has had a difficult four months, warning first in November, and then again in January that profits would fall short of expectations due to the weakness in the auto industry.