What is a Google Colab Notebook?

Google Colaboratory (or Colab) is a hosted Jupyter notebook service that requires no setup to use and provides free access to computing resources. A notebook is an interactive document that combines live executable code, equations, visualizations, and explanatory text in a single place.

Understanding Cell Types

Colab documents are built out of sequential blocks called cells. There are two primary cell types you will use:

• Code Cells: These allow you to write and execute Python code directly in your browser. When you run a code cell, the output is displayed immediately beneath it.
• Markdown Cells: These contain plain text formatted using Markdown syntax. They are used to document your workflow, add explanations, headings, equations, and links.

Accessing Google Colab

To open a new notebook environment, visit the Google Colab Website. You can sign in with your Google account and click New Notebook to start a blank project.

Installing Soft Potato

Before running electrochemical simulations, you need to install the softpotato package into your Colab session environment.

Create a new code cell at the top of your notebook and run the package installation command:

!pip install softpotato

Execute the cell by clicking the play icon on the left or pressing Shift + Enter.

Running the Chronoamperometry Transient Script

Once the package is installed, create a new code cell below, paste the simulation script provided below, and execute it to generate the chronoamperometry plot.

import numpy as np
import matplotlib.pyplot as plt
from softpotato.analytical import cottrell

# Experimental parameters
n = 1
c_bulk = 1.0  # mol/m^3
D = 7.5e-10  # m^2/s
electrode_radius = 1.5e-3  # m
area = np.pi * (electrode_radius**2)

# Time grid
t = np.linspace(0.01, 5.0, 500)

# Calculate current
i_amperes = cottrell(t=t, n=n, D=D, c_bulk=c_bulk, area=area)
i_microamps = i_amperes * 1e6

# Plot
plt.figure(figsize=(7, 4.5))
plt.plot(
    t,
    i_microamps,
    color="#FD8031",
    linewidth=2.5,
    label="softpotato.analytical.cottrell",
)
plt.xlabel("Time (s)")
plt.ylabel("Current (µA)")
plt.title("Installation Verification: Chronoamperometry Transient")
plt.grid(True, linestyle="--", alpha=0.5)
plt.legend()
plt.tight_layout()
plt.show()