Hydrogen is a promising energy carrier. A carbon-free option to produce hydrogen is the photocatalytic splitting of water, when solar radiation provides the photons needed for the reaction. The DLR develops a test bed to assess the activity of potential catalysts either in suspensions or in fixed-bed electrochemical cells under practical sun-light conditions, concentrated by a factor up to 20. A rectangular flat focus is required in order to guarantee a homogeneous distribution of concentrated radiation on the planar receiver plate, where the light enters the receiver. A low deviation of irradiation on the receiver plate promotes a reliable evaluation of the catalysts’ efficiency and quantum yields. This paper is focused on the development of a suitable concentrator concept. A concentrator/receiver-concept featuring a homogeneous distribution of radiation on the reactor surface was chosen after analyzing different options by means of a ray tracing tool. The favorite concept employs a 2-axis modified linear Fresnel collector. The overall dimensions were determined taking the optical properties of the irradiated surface of the reactor into account. A limitation of the angle of incidence ensures that only a marginal fraction of the radiation is lost due to reflection on the irradiated surface of the reactor.

This content is only available via PDF.
You do not currently have access to this content.