Data-Driven Inference of Synthesis Guidelines for High-Performance Zeolite-Based Selective Catalytic Reduction Catalysts at Low Temperatures

Numerous zeolite-based selective catalytic reduction
(SCR) catalysts
have been investigated to improve nitrogen oxide (NOx) removal efficiency
at low temperatures of 25–200 °C in diesel vehicles. However,
the majority of these studies examined only one of each feature’s
effects. The catalysis mechanism consists of complex reactions, and
the various features interact, making it difficult to predict their
combinatorial effects on the catalytic activity. Recently, machine
learning-based models have been widely employed in catalysis science
to infer hidden information about catalysts without knowledge of the
underlying physical principles. Interpretable machine learning models
are particularly useful for catalyst research because they can explain
the causal relationship between characteristics and catalytic performance.
In this study, we construct a machine learning model utilizing a decision
tree, one of the representative interpretable machine learning models.
Using this model, we evaluate the causal relationship between features
and the NOx removal efficiency of zeolite-based SCR catalysts at low
temperatures, which is difficult to deduce due to the high number
of features. Additionally, we extract several synthesis guidelines
for catalysts that show superior NOx removal performance at low temperatures.
New catalysts were synthesized using the proposed rules, and their
performance was validated experimentally.