Electrochemical reduction of carbon
dioxide (CO2) has
received increasing attention with the recent rise in awareness of
climate change and the increase in electricity supply from clean energy
sources. However, because of the complexity of its reaction mechanism
and the largely unknown electron transfer pathways, the development
of a first-principles-based operational model of a CO2 electrocatalytic
reactor is still in its infancy. This work proposes a methodology
to develop a feed-forward neural network (FNN) model to capture the
input–output relationship of an experimental electrochemical
reactor from experimental data that are obtained from easy-to-implement
sensors. This FNN model is computationally efficient and can be used
in real-time to determine energy-optimal reactor operating conditions.
To further account for the uncertainty of the experimental data, the
maximum likelihood estimation (MLE) method is adopted to construct
a statistical neural network, which is demonstrated to be able to
address a usual overfitting problem that occurs in the standard FNN
model. In addition, by comparing the neural network with an empirical
first-principles-based model, it is demonstrated that the neural network
model achieves improved prediction accuracy with respect to experimentally
determined input–output operating conditions. Finally, the
insights obtained from the FNN model and the limitations identified
of the empirical, first-principles model (EFP model) are used to propose
specific modifications to the EFP model to improve its prediction
capability.