A team of researchers at The University of Manchester have found that on a microscopic scale water behaves very differently when only a few molecules thick and its thin layers lose any polarizability, becoming electrically dead.
Such water was previously predicted to exhibit a reduced electric response, but it remained unknown by how much.
The new study shows that atomically thin layers of water near solid surfaces do not respond to an electric field.
For many decades scientists tried without success to figure out how water behaves on a microscopic scale, in the immediate vicinity of other substances, solid surfaces and macromolecules, thus remaining a controversial issue in modern physical chemistry.
There has been a research study based on the work of two teams at the National Graphene Institute at The University of Manchester. The first team was led by Dr Laura Fumagalli and the second by Professor Andre Geim. The research finally succeeded in measuring the dielectric properties of water that is only a few molecules thick.
They achieved this by combining two recently developed technologies. First, the researchers created special channels that were down to several angstroms in size and accommodated only a few layers of water.
Second, they introduced a technique capable of probing water’s dielectric constant inside such nanochannels.
The researchers have found that the electric response of the confined water is not only suppressed but completely absent. In other words, the water inside nanochannels was electrically dead with its dipoles immobilized and unable to screen an external field.
This is in contrast to bulk water whose molecules easily align along an electric field. The thickness of the dead layer was found to be less than one nanometer, two to three molecules thick.