White light emitting diodes packaged with photocatalyst

This study designed a versatile white light emitting diode (WLED) capable of breaking down volatile substances via photocatalytic reactivity produced by ultraviolet (UV) radiation. An optical filter was coated with photocatalytic material on the back side to separate the optical paths of visible and UV light, thereby reducing the possibility of UV leakage. The deodorization capability of the device was measured according to the rate at which ammonia was decomposed in an isolation chamber. Ammonia concentrations were reduced by 30% from the initial value within just two hours.