Piezoelectric materials can change mechanical energy completely to electrical energy, as well as the other way around. Lately, there has been developing interest in the quest for two-layered (2D) layered piezoelectrics. Such layered van der Waals piezoelectrics are especially helpful for specialty applications like actuators with nuclear scale accuracy and wearable sensors. Furthermore, 2D piezoelectrics can be used as nanoscale power generators for nanoscale devices.
The revelation of 2D piezoelectrics has generally been on an impromptu premise. An orderly hunt through a 2D materials data set is expected to reveal 2D materials which are generally appropriate for use as piezoelectrics. The exploration group, led by Associate Professor Quek Su Ying from the Department of Physics, National University of Singapore, performed such a precise hunt through a data set of 2,940 layered van der Waals materials utilizing high-throughput first standards estimations. Of the 2,940 materials, the group recognized 109 materials that show piezoelectric impacts in the single layer structure. Among these materials, around 10 of them are found to have especially huge piezoelectric coefficients, with the most elevated being those for NbOI2. Materials with high piezoelectric coefficients, by and large, give better piezoelectric execution.
The great piezoelectric exhibition of NbOI2 is reflected in its anticipated electromechanical coupling factor, which has the most extreme conceivable level of solidarity in this material. The examination group detached not many layer NbOI2 gems and performed laser checking, concentrating on mass and barely any layer NbOI2 precious stones to gauge their piezoelectric reaction. They found that NbOI2 showed a piezoelectric reaction that is a lot bigger than reference materials in both the mass and not many layer tests.
“There is a lot of application potential for the NbOX2 material class. Our research revealed that among the 2,940 materials in our investigation, NbOI2, one of its members, had the best piezoelectric performance. Additionally, we discovered that its thickness has no effect on its piezoelectric performance. In contrast to other 2D piezoelectric materials like molybdenum disulfide.”
Associate Professor Quek Su Ying from the Department of Physics, National University of Singapore
NbOI2 has a place in a group of niobium oxydihalides (NbOX2: X = Cl, Br, I) which have huge piezoelectric coefficients. The scientists made a more definite investigation of this material family and found that NbOX2 has a natural ferroelectric polarization as its gem structure isn’t even in the x-course). Strangely, the piezoelectric coefficients are the biggest for NbOI2, while the ferroelectric polarization is the biggest for NbOCl2.
Prof. Quek said, “The class of NbOX2 materials has incredible potential for applications.” Our work showed that one of its individuals, NbOI2, had the best piezoelectric exhibition among the 2,940 materials in our review. Besides, we observed that its piezoelectric execution is free of thickness. This is dissimilar to other 2D piezoelectrics, for example, molybdenum disulfide, where the piezoelectricity is absent when there is a large number of layers. The thickness-freedom of piezoelectricity in NbOX2 is helpful for viable applications where the control of the material thickness might pose an especially challenging challenge. “
More information: Yaze Wu et al, Data-driven discovery of high performance layered van der Waals piezoelectric NbOI2, Nature Communications (2022). DOI: 10.1038/s41467-022-29495-y
Journal information: Nature Communications
