A few years back NASA did a study to determine which indoor plants best cleaned the air and came up with a top 25 list. Many of the the plants that Everything Grows offers with its interior plant service are on the list.
One of them is the Ficus Decora known as the Rubber Plant. It is a hardy indoor plant that can tolerate lower light levels found in indoor environments. Not only does this plant produce oxygen from Carbon Dioxide, but it also absorbs harmful benzene, formaldehyde and/or trichloroethylene.
Here is a picture of a small Ficus Decora with dark shiny leaves:
