Skip to main content

Defect & Dopant Predictions for Thermoelectric Materials

Mar 20, 2018
(Left) Dopability range predictions (red) follow trends of experimental results (blue) for ~100 diamond-like semiconductors. (Above) LiZnSb has been repeatedly predicted to be a world-class thermoelectric material, but our calculations demonstrate it cannot be n-type doped due to vacancy formation.
(Left) Dopability range predictions (red) follow trends of experimental results (blue) for ~100 diamond-like semiconductors. (Above) LiZnSb has been repeatedly predicted to be a world-class thermoelectric material, but our calculations demonstrate it cannot be n-type doped due to vacancy formation.

Challenge: Defects and scarcity of dopants often are the Achilles heel to realizing the theoretical potential of new semiconductors (eg transparent conductors, thermoelectrics). Further, native defects and dopants are computationally expensive to accurately calculate.  Two approaches to overcome this challenge are in progress:  

Approach 1: Experimental training sets concerning dopability have been assembled and serve as the basis for machine learning models to predict the maximum dopability range in materials (left Figure). We have achieved predictive dopability, with carrier concentration predicted within one order of magnitude.

Approach 2: Rather than relying on experimental literature and our on-going experimental efforts to build a training set, a similar database has been constructed using DFT calculations of defects in model systems.  We have validated the defect calculations against experimental measurements.

Union: Looking forward, we will combine these two training sets to provide greater predictive accuracy.

Authors

https://dmref.org/files/13bc53a2-6be6-4e57-855e-ff7d538df0c1

Additional Materials

U.S. National Science Foundation and NSF DMREF, Materials for Our Future

This material is based upon work supported by the U.S. National Science Foundation Award No. 2015237. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the U.S. National Science Foundation. This site is maintained collaboratively by principal investigators with NSF DMREF awards, independent of the NSF.