The website Care2, has a list of 20 plants that can help with everything from:
..reduc[ing] the chance of getting seasonal sicknesses (such as the common cold), remove airborne contaminants (volatile organic compounds [or VOCs]), reduce the chance of headaches, lift your mood, decrease your blood pressure, reduce allergies, improve sleep and much more.
The 20 plants listed below are specifically known for their air purifying properties. And while an open window may feel like all the fresh air you need, did you know that everything from toilet paper to common household cleaners can contain chemicals and release toxins like formaldehyde? Or that VOCs like benzene can be released into the air by everything from the paint on your walls, to the printed material found in your home?
More plants and information here. The article also mentions what toxins each one helps eliminate.