Reported synthetic conditions of carbon nitride (CNx) do not directly correlate with photocatalytic activities

Correlating individual synthetic and measured parameters of carbon nitride (CN x ) with its photoactivity to unravel its structure-activity relationship remains elusive. We utilize the design of experiments approach, based on the Latin hypercube sampling method, as a technique to obtain a tractable number of CN x samples prepared under a broad range of synthetic conditions (5 parameters, 2 - 4 levels each). This approach led to twenty-four different synthetic conditions that each yield a different CN x material. The set of CN x s were evaluated by benchtop techniques including the photocatalytic H 2 production activity, FTIR, UV-vis diffuse reflectance, photoluminescence spectroscopy, and transient absorption spectroscopy. The link between synthetic parameters, spectroscopic features, and activity of the CN x materials were explored by Pearson correlations, machine learning models, and Principal Component Analysis. The three different multivariate analyses all identify that opto-electronic properties measured post-synthetically have stronger correlations with the photocatalytic activity compared to the synthetic conditions. • Design of experiment was used to generate a large set of 24 carbon nitrides. • Provide rich dataset from synthetic conditions and characterization results. • Multivariate analyses show that synthetic conditions don’t predict activity. • Post-synthetic optoelectronic properties correlate more strongly to activity.