Illustration of the Sabatier principle in heterogeneous catalysis. Inspired by From the Sabatier principle to a predictive theory of transition-metal heterogeneous catalysis.
\documentclass[tikz]{standalone}
\usetikzlibrary{shapes}
\begin{document}
\begin{tikzpicture}[thick, align=center]
\fill[blue!20] (0,0) rectangle (4.5,4);
\fill[orange!20] (4.5,0) rectangle (8,4);
\node at (2.5,1) {limited by\\desorption\\of product};
\node at (6,1) {limited by\\activation\\of reactant};
\node[ellipse, fill=teal!50, inner sep=2pt] at (4.5,4.2) {Sabatier\\optimum};
\draw[->] (-1,0) -- (8,0) node[below, pos=0.17] {weak} node[below, pos=0.55, font=\bfseries] {bond strength} node[below, pos=0.92] {strong};
\draw[->] (0,-1) -- (0,5) node[below right, font=\bfseries] {reaction rate};
\draw[rounded corners=5ex, very thick] (0,1) -- (4.5,4) -- (8,1);
\end{tikzpicture}
\end{document}
#import "@preview/cetz:0.3.2": canvas, draw
#set page(width: auto, height: auto, margin: 8pt)
#canvas({
import draw: line, content, rect, hobby, circle
// Draw background rectangles
rect(
(0, 0),
(4.5, 4),
fill: rgb(200, 220, 255), // blue!20
stroke: none,
)
rect(
(4.5, 0),
(8, 4),
fill: rgb(255, 230, 200), // orange!20
stroke: none,
)
// Draw axes
let arrow-style = (mark: (end: "stealth", fill: black, scale: 0.7), stroke: black + 1pt)
let axis-overshoot = -0.75
line((axis-overshoot, 0), (8, 0), ..arrow-style, name: "x-axis") // x-axis
line((0, axis-overshoot), (0, 5), ..arrow-style, name: "y-axis") // y-axis
// Add axis labels
content((rel: (-axis-overshoot, -0.2), to: "x-axis.6%"), "weak", anchor: "north")
content((rel: (-axis-overshoot, -0.25), to: "x-axis.50%"), text(weight: "bold")[bond strength], anchor: "north")
content((rel: (0, -0.2), to: "x-axis.95%"), "strong", anchor: "north")
content((rel: (0.1, 0), to: "y-axis.95%"), text(weight: "bold")[reaction rate], anchor: "west")
// Add region labels
content(
(2.5, 1),
align(center)[limited by\ desorption\ of product],
)
content(
(6, 1),
align(center)[limited by\ activation\ of reactant],
)
// Draw Sabatier optimum label
let ellipse-center = (4.5, 4.2)
let ellipse-width = 1.2
let ellipse-height = ellipse-width / 2
// Draw ellipse background
circle(
ellipse-center,
radius: (ellipse-width, ellipse-height),
fill: teal,
stroke: none,
)
// Draw volcano curve using hobby spline
hobby(
(0, 1),
(2, 2.6),
(4.5, 3.7),
(6, 2.8),
(8, 1),
stroke: black + 1.2pt,
omega: 1,
)
// Add label
content(
ellipse-center,
align(center)[Sabatier\ optimum],
padding: 2pt,
)
})