Air purifier

An air purifier is provided, including a body (14) comprising a wall (16) defining an interior space (18), a first opening (20) to the interior space, and a second opening (22) to the interior space. The body is a tubular body. An airflow pathway is provided through the tubular body defined between the first and second openings. A source of ultraviolet radiation (36) is arranged to emit ultraviolet radiation into the interior space. A photocatalyst (34) is arranged within the interior space and along the airflow pathway, and the ultraviolet radiation can be emitted onto at least a portion of the surface of the photocatalyst to activate the photocatalyst. In one example, the wall includes an aperture (40), and a cover (42) is coupled to the body about the aperture and configured to enclose the source of ultraviolet radiation. In another example, the air purifier includes turbulence structure (52).