Illustration of an assembled set of different molecules that meet, exchange electrons and then disassemble because chloride ions, which are represented as green spheres, are present â€“ if these chloride ions are removed, the entire process can be reversed (Image: Jung Su Park)
There’s no arguing that batteries are an essential element of today’s electronics landscape. Without them our mobile devices would be a lot less mobile and we might still be crank starting our cars. The explosion in mobile electronic devices enabled by batteries and miniaturization has a major downside in the form of discarded batteries, the majority of which contain toxic heavy metals. Chemists have now discovered a new way to pass electrons back and forth between two molecules that could see the development of organic batteries that are lightweight and work without the need for toxic heavy metals.
Batteries consist of electrochemical cells that store energy in the form of chemical energy, which is converted into electrical energy when connected to an electrical circuit in which an electrical current can flow. When molecules meet, they often form new compounds by exchanging electrons. In some cases, the electron transfer process creates one molecule with a positive charge and one molecule with a negative charge. Molecules with opposite charges are attracted to each other and can combine to form something new.
In their research, University of Texas at Austin chemists Christopher Bielawski and Jonathan Sessler created two molecules that could meet and exchange electrons but not unite to form a new compound.