Articial Neural Networks for Accurate Prediction and Analysis of Perovskite Bandgaps

Tuesday, 15 October 2019
Grand Ballroom (The Hilton Atlanta)
Z. Stoichev, O. A. Allam, and S. S. Jang (Georgia Institute of Technology)
Perovskites are a unique class of semiconductors with long carrier diffusion lengths which have shown remarkable promise for photovoltaic applications as their solar conversion efficiencies increased rapidly by nearly 20% over the past decade. Here we evaluate the efficacy of artificial neural networks for the analysis and prediction of 3D perovskite band gaps; which is the key parameter used in solar cell design. The set of input parameters for our artificial neural network includes descriptors such as s, p, d, and f orbital radii, electronegativity, octahedral factor, and formation energy. Furthermore, we apply a recursive feature correlation filter to eliminate features which highly correlate with other features in our model as well as features which have a low contribution with regards with regards to predicting bandgap. We find that splitting the dataset between training, testing, and validation sets in a 70:15:15 ratio provides a highly reliable model that yields a mean square error of less than 0.25 eV. We then validate the capability of artificial neural network by testing its predictability for bandgaps based on unseen inputs.