Machine Learning for Estimating Electron Transfer Rates From Square Wave Voltammetry

Chempluschem. 2021 Nov 12;87(1):e202100418. doi: 10.1002/cplu.202100418. Online ahead of print.

Abstract

Electrochemistry of surface-bound molecules is of high importance for numerous electronic and sensor applications. Extracting the electron transfer rate is beneficial for understanding surface-bound processes, but it requires experimental or computational rigor. We evaluate methods to determine electron transfer rates from large voltammetry sets from experiments via machine learning using decision tree ensembles, neural networks, and gaussian process regression models. We applied these to reproduce computational measures of electron transfer rates modeled by first principles. The best machine learning models were a random forest with 80 decision trees and a neural network with Bayesian regularization, producing root mean squared errors of 0.37 and 0.49 s-1 , respectively, corresponding to mean percent errors of 0.38 % and 0.52 %, respectively. This work establishes machine learning methods for rapidly acquiring electron transfer rates across large datasets for widespread applications.

Keywords: artificial intelligence; charge transfer; cyclic voltammetry; decision trees; electrochemical kinetics.