Future electronics and computer components may incorporate a range of new 2D ferroelectric materials that UNSW and Flinders University researchers recently described in a new Nature journal article.

Van der Waals (vdW) ferroelectrics – which are structurally different from conventional oxide ferroelectrics with rigid lattices – have stable layered structures with a combination of strong intralayer and weak interlayer forces, as identified by the researchers in the Nature Review Materials article.

Dr Pankaj Sharma, from Flinders University College of Science and Engineering, and UNSW collaborators from the ARC Centre of Excellence in Future Low-Energy Electronics Technologies (FLEET) say that future applications include ultra-low energy electronics, high-performance and non-volatile data-storage, high-response optoelectronics and flexible (energy-harvesting or wearable) electronics.

“It’s a relatively new field, so there are still many challenges that need to be solved to realise the full technological potential of these materials,” says co-author Dr Sharma.

“For example, we need to address large-area, uniform, wafer-scale growth and integration methods. These will allow the development of futuristic low-energy electronics and computing solutions.”

At Flinders University, Dr Sharma leads experimental studies of nanoscale ferroelectrics and devices utilising cutting-edge scanning probe microscopy and spectroscopic techniques for developing low-energy electronics and data storage applications. His key contributions to this field include demonstrating a novel electronic materials class – ferroelectric metals, and low-energy ferroelectric wall memory technology.

The special atomic arrangement in these materials, in combination with the ferroelectric order, give rise to fundamentally new phenomena and functionalities not found in conventional materials, according to the research team.

“Fundamentally new properties are found when these materials are exfoliated down to atomically thin layers,” says UNSW co-author Dr Dawei Zhang.

“For example, the origin of the polarisation and the switching mechanisms for the polar order can be different from conventional ferroelectrics, enabling new material functionality.”

One of these materials most intriguing aspects is their easily stackable nature because of the weak van-der-Waals interlayer bonds, which means that vdW ferroelectrics are readily integrable with highly dissimilar crystal-structure materials, such as industrial silicon substrates, without interfacial issues.

“This makes them highly attractive as building blocks for post-Moore’s law electronics,” says UNSW co-author Professor Jan Seidel.

• A new solar perovskite cell nano research article in  Advanced Energy Materials also features the work of other Flinders University researchers. The team of researchers from Monash University, ANU, Flinders University, The University of Sydney and the Karlsruhe Institute of Technology achieved a record-breaking 30.3% efficiency in a perovskite and silicon tandem solar cell.