Illuminating Innovations: Accelerated Discovery of Structure-Activity Relationships in Solar Fuels Chemistry

Abstract:

Illuminating Innovations: Accelerated Discovery of Structure-Activity Relationships in Solar Fuels Chemistry

This presentation highlights innovative methods for exploring the intricate interactions between reagents and catalysts in light-driven chemical processes crucial for solar fuel production. Newly developed 96-well photo-reactors have significantly enhanced and accelerated the measurement of photocatalytic rates and turnover numbers in processes such as photocatalytic alcohol reforming, photoredox transformations, and light-driven metal reductions. These reaction rates were determined using a camera-based detection system with indicator dyes and gas-sensitive films.

Thousands of reaction conditions, catalysts, and chromophores were examined using an infrastructure built from single-board computers, 3-D printers, laser cutters, and other tools popular in the Maker culture. Advanced data science and machine learning techniques were employed to identify trends in the structure-activity databases. Special attention was given to the [Ir(CN)₂(NN)]⁺ family of luminophores, with libraries created from cyclometalating C^N and 1,2-diimine N^N ligands, resulting in a vast array of structurally and electronically diverse photocatalyst structures. The newest result will expand these studies to Rh-based chromophore libraries.

Thousands of rates and turnover numbers for hydrogen photogeneration were measured using these photosensitizer libraries, as shown in Figure 1. The presentation will also detail the path to develop hydrogen-sensitive films along with the calibration methods used to quantify the colorimetric response. The latest research focused on light-driven water oxidation reactions, with oxygen evolution measured by O₂-sensitive film in parallel on multi-well reactors.