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

phenyl-C -butyric-acid methyl ester (PC BM) in chlorobenzene at 1,200 rpm for 60 s followed by spin-
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coating 60 µL of a 0.5 mg/mL bathocuproine (BCP) solution in ethanol at 4,000 rpm for 30 s. The top
electrodes were deposited by thermal evaporation of 100 nm of Al followed by 50 nm of Ag. The diode area
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is 0.11 cm .

Materials characterization
Device current density - voltage (J-V) measurements were taken using a 2635A Keithly source meter under
an AM 1.5G 100 mW/cm illumination from an AAA solar simulator (Abet). Using a 0.0491 cm aperture,
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device forward scans were measured using a voltage sweep of -0.2 to 1.2 V with reverse scans sweeping from
1.2 to -0.2 V at 70 mV/s. The following material characterization techniques were taken on TA/PC MAPbI
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film samples on unpatterned ITO substrates. X-ray diffraction (XRD) patterns for each condition were
measured using a Rigaku Mini Flex diffractometer at a scan speed of (3°/min) with Cu Kα radiation (λ =
1.518 Å). Scanning electron microscope (SEM) images of MAPbI films were taken using a Zeiss Supra 40
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SEM at an acceleration voltage of 5 kV in a 7:3 InlenseDuo:SE2 mode. Atomic force microscopy (AFM) was
performed on at least three 5 × 5 μm areas using an Asylum Research MFP-3D system. MAPbI film
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thickness was measured using a Keyence optical profilometer (VK-X3100) in a laser confocal mode.
Absorbance data for all TA/PC MAPbI films was measured using an Ocean Optics USB 4000 spectrometer.
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PC on MAPbI and temperature simulation
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PC of MAPbI thin films was performed using a 500 V / 3 A PulseForge Invent system with a single lamp
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driver. Prior to pulsing a sample, the radiant energy for each PC condition was verified using a National
Institute of Standards and Technology (NIST)-traceable bolometer. Samples were pulsed with the
appropriate PC condition within 30 s after spin-coating. The pulsing procedure would involve securing the
sample face-up onto the PulseForge Invent platform with two magnetic strips. Successful observation of
crystallization is indicated by a color change from light brown to dark brown with a shiny appearance,
similar to fully converted TA MAPbI films, immediately after PC.
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Simulations of temperature vs. time for all PC samples were made using the built-in software SimPulse®.
Simulated temperatures for each condition were taken on a material stack consisting of (from top down)
MAPbI (270 nm), ITO (155 nm), and soda-lime glass (1.1 mm). MAPbI film thickness was nominally the
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same for all TA/PC annealing conditions [Table 1]. ITO and glass thickness were verified via specifications
provided by the manufacturer. The thermal and optical properties for temperature simulations of ITO and
glass were built into the SimPulse® database. All simulated material properties are available in
Supplementary Table 2.

ML method
Initial sampling
Initial PC conditions were chosen using a quasi-random Latin Hypercube Sampling (LHS) for the four PC
parameters on the PulseForge Invent tool in “µpulse” mode. The four input parameters (range, increment)
correspond to the pulse length (10-50 ms, in steps of 0.1 ms), radiant energy (3.0-13.5 J/cm , in steps of
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0.1 J/cm ), number of µpulses (2-30, in steps of 1), and the duty cycle (20%-70%, in steps of 5%). The ranges
were determined by the limit of the instruments or the desired outcome. For example, radiant energy above
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13.5 J/cm completely ablates the MAPbI films. The ranges and increments for the four inputs result in over
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13 million combinations, which is impossible to investigate with traditional methods. A set of 20 initial LHS
conditions was selected from these combinations in a space-filling method to survey the outcomes for the
defined input space [Supplementary Table 1].