Researchers are saying that hexagonal boron nitride or h-BN can effectively prevent overheating of small electronics. For those who don’t know: hexagonal boron nitride is more commonly referred to as white graphene. Recently a research team representing the Rice University has released the very first theoretical analysis of the process of using white graphene as a tunable material for controlling the flow of heat in electronic devices of daily use.
White graphene is similar to conventional graphene as far as its appearance is concerned. The only difference between the two is that while white graphene can play the role of an insulator, regular graphene cannot provide any barrier to electricity. Both graphene and h-BN, however, are good conductors of heat, which indicate that the latter would be an ideal material to be used for controlling the production of heat within electronic devices.
Rouzbeh Shahsavari, a Rice researcher, involved in the study, said that it’s a common expectation from all electronics that heat gets out of the system as efficiently and quickly as possible. He added that a notable drawback electronics come with, especially when there are layered materials on the base, is that rapid heat flow occurs in a particular direction along a conductive plain, while between layers the flow remains quite subdued. When explaining this drawback of electronics Shahsavari used multiple stacked graphene layers as an example.
The researchers used computer simulations to demonstrate that 3D structures of white graphene planes that were linked with each other by means of boron nitride nano-tubes possess the ability to move phonons in every direction. Next, the researchers calculated how these phonons will be using nano-tubes of various densities and lengths for moving across the four different structures.
Eventually, the team found that the junctions of planes and pillars played the role of “yellow traffic lights” by significantly slowing down the flow of phonons from one layer to another.
Shahsavari said that boron nitride’s insulating properties allowed it to complement and enable the creation of graphene-based, 3D nanoelectronics. According to him, 3D thermal management systems of this type might give birth to thermal rectifiers or thermal switches, in which heat flowing in a given direction can vary from heat flowing in its opposite direction. Shahsavari informed that doing this is possible just by altering the shape or mass of the material.
The entire study can be read on the latest edition of the widely read journal American Chemical Society.