Which plants are healthy to keep in the bedroom at night?
There exist a diversity of flora you may select relative to the antigen or noxious chemical you seek to reduce. 
Pursuant to the British Medical Bulletin, the critical indoor pollutants are the polycyclic aromatic hydrocarbons like furanes and benzenes, ethanal (formaldehyde) and carbon monoxide. Depending upon which gaseous or volatile compound you seek to reduce in your household, you may select Chrysanthemum morifolium for the reduction of ammonia gas, xylene and alternative respiratory irritants; Chlorophytum chomosum for formaldehyde; and Dracaena genus concerning and trichloroethylene. 

If you should suffer any infestation of Penicillium mould, then it is advised that one tackle the source of the infestation directly - areas rich in cellulose and moisture. 

Further information regarding is available from the following links: 

9 Air-Cleaning plants that are almost impossible to kill, https://greatist.com/connect/houseplants-that-clean-air

British Medical Bulletin, https://academic.oup.com/bmb/article/68/1/209/421251