Making photocatalysts screenable – a milliscale multi-batch screening photoreactor as extension for the modular photoreactor

Abstract

Development and evaluation of new photocatalytic systems requires screening of large parameter spaces. For such investigations, a photonically characterized, simple, and low-cost multi-batch screening photoreactor is presented that enables the screening of up to 49 sealed 4 mL milli batch reactors. The reactor concept is based on theoretical contemplation of the geometrical and optical properties of suited reflector concepts and utilizes basic components of the modular photoreactor introduced recently. Raytracing, radiometry and chemical actinometry were used for the photonic characterization. Applicability of the screening setup under catalytic conditions was evaluated using a benchmark system for photoinduced hydrogen evolution consisting of [Ru(bpy)₃](PF₆)₂ as the photosensitizer, ascorbic acid as a sacrificial agent and Mo₃S₁₃²⁻ as the catalyst. Extending screening to metal-free organic photosensitizers, bimane compounds are reported as photosensitizers for photoinduced hydrogen evolution in various catalytic systems.