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Allen et al. J Mater Inf 2024;4:35 https://dx.doi.org/10.20517/jmi.2024.72 Page 7 of 15

The first round of GP-generated conditions consists of PC 20 to PC 23 in Supplementary Table 2 and
corresponds to a single new condition picked according to each of the four GP models. The four new
conditions did not add any significant information about the dataset with none of the conditions producing
a film with a new champion distance among any of the metrics. The models were rerun with the addition of
these new data points, and the second round of GP-generated conditions (PC 24 to PC 26) were picked as
the next most promising optimization conditions for the models trained on the first three similarity metrics
(excluding RMSD due to overfitting). Condition PC 25, suggested by the Fréchet distance model, showed a
particularly strong similarity to the TA reference. It was the only condition to achieve Procrustes distance
values of 10 and one of only two conditions to yield Fréchet and RMS distances < 2.0 × 10 . UV-vis
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spectra of MAPbI made using PC 03 (6.8 J/cm ), PC 04 (12.2 J/cm ), and PC 25 (11.5 J/cm ) are shown in
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Figure 1. PC 03, PC 25, and PC 04 are chosen to represent PC MAPbI films produced with low, optimal,
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and high radiant energy conditions. PC 03, a lower-energy condition, shows a clear UV-vis shift, although
its Fréchet distance is small [Table 1]. In contrast, PC 04, a higher-energy condition, may appear not too
different from the TA reference at first glance but has a poor Fréchet distance.
The low similarity metrics of PC 25 suggest that we have found an optimized PC condition that can produce
MAPbI films with the same UV-vis absorption spectrum as the TA sample. To verify the conversion, we
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created a final round of conditions (PC 27 to PC 30) that were all picked from the model trained on Fréchet
distances. None of the new four conditions produced similarity metrics better than PC 25, and we
concluded that the model was properly trained. Figure 2A corresponds to the final heat maps of the
expected maximum values of the inverted scaled Fréchet distance in each pair of input parameters of all
available PC conditions with the color-coded points corresponding to each round of LHS and GP-generated
PC conditions with the best condition, PC 25, marked with a “red star”. The calculation of inverted scaled
values of the Fréchet distance is detailed in the Supplementary Materials. Figure 2A clearly shows that the
model has converged to an “optimal area” within the input parameter space. This area generally
corresponds to a condition with a medium pulse length (> 20 ms), relatively higher radiant energy
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(9-12 J/cm ), a large number of µpulses (> 20), and a mid-ranged duty cycle (40%-60%). The fact that the
model is neither overfitted nor underfitted in Figure 2A strengthens our confidence that the correct
hyperparameters were selected. The associated parity plot for measured vs. predicted outputs for the Fréchet
distance model is shown in Figure 2B. A slope of near unity and a small y-intercept suggest that the
surrogate model accurately represents the experimental data. The heat maps and parity plots for models
trained on the other three metrics are shown in Supplementary Figures 1 and 2, respectively.

Material properties for photonic cured MAPbI 3
To evaluate the quality of the MAPbI produced via PC, PC MAPbI films for the three conditions PC 03,
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PC 25, and PC 04 representing films produced with low, optimal, and high radiant energies were examined.
We first performed XRD on all MAPbI films and a precursor film [Supplementary Figure 3]. For all
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annealed samples, tetragonal MAPbI perovskite is the dominant crystalline feature with strong intensities
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displayed for the (110) and (220) major reflections at 14.2° and 28.4°, respectively. The TA sample and the
two higher radiant energy PC samples show a small PbI (001) peak at ~12.7°. The lower radiant energy
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condition (PC 03) and the precursor film both share a small peak around 8.2°, consistent with an
[24]
intermediate MAPbI phase for 2-MOE-based, NMP-assisted MAPbI . Previous works on PC of DMF/
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dimethyl sulfoxide (DMSO)-based MAPbI using radiant energy similar to PC 03 also contained residual
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[11]
DMSO adducts . The peak intensity for the (110) MAPbI crystallographic reflection normalized to the TA
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sample served as the benchmark for the crystallinity of PC samples. Table 1 shows that the crystallinity of
PC samples increases with increasing radiant energy.