A photocatalytic device comprising Manganese dioxide and Titanium dioxide coated housing, an ultraviolet light source disposed therein, and a plurality of multi-metallic photocatalytic structures, such as hydrated multi-metallic catalyst substrates, is adapted to be deployed in conjunction with the exchange air intake of a mini-split system. The photocatalytic device has (a) Manganese dioxide and Titanium dioxide coated reflector(s) that is/are positioned to reflect ultraviolet light onto the photocatalytic structures. The photocatalytic device may have at least one carbon fiber and/or needle type ionizer disposed in the housing. The photocatalytic device may also have at least one sensor and may be wirelessly coupled to a computing device or controller.
