How Non-Ohmic Contact-Layer Diodes in Perovskite Pinholes Affect Abrupt Low-Voltage Reverse-Bias Breakdown and Destruction of Solar Cells

This repository contains essential data (largely current-voltage data and current-time data) to reproduce figures in the manuscript of the referenced article. Some code to plot raw data is provided, but we expect that users will be able to write their own simple plotting code. This repository contains a larger analysis code (Python via Jupyter Notebook) to produce the model curves that simulate the current-voltage curves of solar cells with various pinhole defects. This repository does not contain raw image data.

Data:
BCP_TLD_data.xlsx --- Current-voltage data from perovskite-free transport-layer diodes (TLDs) with BCP ETLs. Various HTLs are separated into sheets.
SnOx_TLD_data.xlsx --- Current-voltage data from perovskite-free TLDs with SnOx ETLs. Various HTLs are separated into different sheets in the file.
K21_13_PxD_JV.txt --- Current-voltage data from the solar cell recorded during video thermography (Fig. 1e)

Folders:
Fig_1b_JV_curves --- Current-voltage data for all cells in Fig. 1b of the manuscript.
Fig_3G --- all TLD current-voltage data for 12 mm^2 and 200-micrometer diameter TLDs.
Fig_3H --- all TLD current-time (fixed voltage) data for 12 mm^2 and 200-micrometer diameter TLDs.
Fig_5B_12mm2 --- Current-voltage data from 12mm^2 cells
Fig_5B_0.032mm2 --- Current-voltage data from 200-micrometer diameter cells
Fig_5D --- Reverse-bias current-voltage scans from 200-micrometer diameter cells
Fig_5E --- Forward-bias current-voltage scans from 200-micrometer diameter cells *after* reverse-bias scans
Fig_5F --- Current-time data from fixed-voltage holds at -2.5 V on 200-micrometer diameter cells (data should be plotted with respect to the absolute start time in the filename after '*T*')
SI_Figure_26 --- Current-voltage data from cells used for thermography imaging with metal (26C) and ITO (26F) top contacts.

Codes:
Double_Diode.ipynb

The code Double_Diode.ipynb is used to calculate the current-voltage behavior of a solar cell with TLD-type pinholes. It is described in more detail here. The curves produced from this code assume TLD behavior derived by fitting the TLD data contained in 'BCP_TLD_data.xlsx' and 'SnOx_TLD_data.xlsx'. The "solar cell" area is define as an ideal p-i-n diode with characteristics taken from typical experimental values. The total model is described in the manuscript. Each diode is assigned a scaling factor of "phi", the area of the pinhole divided by the total area multiplied by the total number of pinholes. Pinholes are assumed circular and the size is defined by a pinhole radius (in micrometers) and then phi is calculated and applied to the total current density. We include the information on the fitting processes in the Supplementary Information.