Common pitfalls in chemical actinometry

Combining microflow chemistry and photoreaction technology has shown to be a viable option to intensify and significantly improve photochemical processes in terms of control and efficiency. Chemical actinometry allows to measure the actually incident photon flux in a specific reactor, but is not trivial to perform. Especially under flow conditions. Numerous errors can occur, not only in the experimental and analytical procedure, but also in the subsequent calculations before finally receiving the incident photon flux. Nevertheless, knowledge of this metric is of fundamental importance to determine the efficiency of photochemical reactor setups. Consequently, this work illustrates, comments and explains various possible pitfalls of chemical actinometry. To avoid adulterated results, a standard measurement and calculation procedure is proposed.