A high-purity gas–solid photoreactor for reliable and reproducible photocatalytic CO2 reduction measurements

• Published in: HardwareX Vol. 15; p. e00448
• Main Authors: Moustakas, Nikolaos G., Klahn, Marcus, Mei, Bastian T., Pougin, Anna, Dilla, Martin, Peppel, Tim, Ristig, Simon, Strunk, Jennifer
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-09-2023; Elsevier
• Subjects: Gas-phase photoreactor; Heterogeneous photocatalysis; High-purity conditions; Photocatalytic CO2 reduction; High-purity conditions; Gas-phase photoreactor; Photocatalytic CO2 reduction; Heterogeneous photocatalysis
• ISSN: 2468-0672; 2468-0672
• DOI: 10.1016/j.ohx.2023.e00448

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•A high purity photoreactor design for reliable CO2 photoreduction experiments.•Design taking into consideration all sources of carbon containing impurities.•High reproducibility of product yields through different iterations of the reactor.•Reactor design and experimental process comply with DIN SPEC 91457.
Reactions between a gas phase and a solid material are of high importance in the study of alternative ways for energy conversion utilizing otherwise useless carbon dioxide (CO2). The photocatalytic CO2 reduction to hydrocarbon fuels like e.g., methane (CH4) is such a potential candidate process converting solar light into molecular bonds. In this work, the design, construction, and operation of a high-purity gas–solid photoreactor is described. The design aims at eliminating any unwanted carbon-containing impurities and leak points, ensuring the collection of reliable and reproducible data in photocatalytic CO2 reduction measurements. Apart from the hardware design, a detailed experimental procedure including gas analysis is presented, allowing newcomers in the field of gas–solid CO2 reduction to learn the essential basics and valuable tricks. By performing extensive blank measurements (with/without sample and/or light) the true performance of photocatalytic materials can be monitored, leading to the identification of trends and the proposal of possible mechanisms in CO2 photoreduction. The reproducibility of measurements between different versions of the here presented reactor on the ppm level is evidenced.