{ "cells": [ { "cell_type": "markdown", "id": "directed-wound", "metadata": {}, "source": [ "Jochen Kieninger
\n", "**Electrochemical Methods for the Micro- and Nanoscale**
\n", "www.electrochemical-methods.org\n", "\n", "## Task 6.1 (Rotating ring disk electrode - collection efficiency)\n", "\n", "The collection efficiency of an RRDE depends on geometrical parameters only, assuming stable reaction products. The radii are $r_1$ for the disk, $r_2$ the inner and $r_3$ the outer of the ring." ] }, { "cell_type": "code", "execution_count": 1, "id": "moved-library", "metadata": {}, "outputs": [], "source": [ "import numpy as np" ] }, { "cell_type": "code", "execution_count": 2, "id": "characteristic-registration", "metadata": {}, "outputs": [], "source": [ "r1 = 2.5 # mm (disk radius)\n", "r2 = 3 # mm (inner ring radius)\n", "r3 = 4 # mm (outer ring radius)" ] }, { "cell_type": "markdown", "id": "hybrid-privilege", "metadata": {}, "source": [ "- For the collection efficiency $N$, Albery and Bruckenstein (https://dx.doi.org/10.1039/tf9666201920) proposed a generally accepted solution:" ] }, { "cell_type": "code", "execution_count": 3, "id": "surgical-little", "metadata": {}, "outputs": [], "source": [ "a = (r2/r1)**3 -1\n", "b = (r3/r1)**3 - (r2/r1)**3" ] }, { "cell_type": "code", "execution_count": 4, "id": "portuguese-sixth", "metadata": {}, "outputs": [], "source": [ "def FF(x):\n", " result = np.sqrt(3)/4/np.pi\n", " result *= np.log((1+x**(1/3))**3/(1+x))\n", " result += 3/2/np.pi*np.arctan((2*x**(1/3)-1)/np.sqrt(3))\n", " result += 0.25\n", " return result" ] }, { "cell_type": "code", "execution_count": 5, "id": "endangered-silence", "metadata": {}, "outputs": [ { "data": { "text/plain": [ "0.4" ] }, "execution_count": 5, "metadata": {}, "output_type": "execute_result" } ], "source": [ "N = 1-FF(a/b) + b**(2/3)*(1-FF(a))\n", "N = N - (1+a+b)**(2/3)*(1-FF(a/b*(1+a+b)))\n", "round(N, 2)" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.9.1" } }, "nbformat": 4, "nbformat_minor": 5 }