Spectral radiative analysis of bio-inspired H2 production in a benchmark photoreactor: A first investigation using spatial photonic balance

The iron–thiolate complex [Fe₂(μ-bdt)CO₆] (bdt = 1,2-benzenedithiolate) is a simplified model of the active site of diiron hydrogenase enzymes. Here, we describe the implementation of this noble-metal-free catalyst in aqueous solutions using eosin Y as photosensitizer and triethylamine as an electron donor in an experimental bench specially designed for the study of H₂ photoproduction. The bench is composed of an adjustable visible light source, a fully equipped flat torus photoreactor and analytical devices. Rates of H₂ production under varied experimental conditions were obtained from an accurate measurement of pressure increase. A spectral radiative analysis involving blue photons of the source primarily absorbed has been carried out. Results have proven the rate of H₂ production is proportional to the mean volumetric rate of radiant light absorbed demonstrating a linear thermokinetic coupling. The bio-inspired catalyst has proven non-limiting and reveals interesting capabilities for future large scale H₂ production.