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The development of porous ceramic screens with high chemical stability, low density, and thermal conductivity can lead to promising screen channel liquid acquisition devices (SC-LADs) for propellant management under microgravity conditions in the future. Therefore, SiOC screens with aligned pores were fabricated via freeze-casting and applied as a SC-LAD. The pore window sizes and open porosity varied from 6 µm to 43 µm and 65 % or 79 %, depending on the freezing temperature or the solid loading, respectively. The pore window size distributions and bubble point tests indicate crack-free screens. On the one hand, SC-LADs with an open porosity of 79 % removed gas-free liquid up to a volumetric flow rate of 4 mL s−1. On the other hand, SC-LADs with an open porosity of 65 % were limited to 2 mL s−1 as the pressure drop across these screens was relatively higher. SC-LADs with the same open porosity but smaller pore window sizes showed a higher pressure drop across the screen and bubble ingestion at higher values of effective screen area when increasing the applied removal volumetric flow rate. The removed liquid from the SC-LADs was particle-free, thus representing a potential for applications in a harsh chemical environment or broad-range temperatures.

Porous SiOC tapes were studied as anodes for bioelectrochemical system (BES) using Geobacter spp. as an electroactive microorganism (EAM). The ceramic anodes were produced by tape‐casting of poly(silsesquioxanes), tailoring the surface properties by incorporating graphite and carbon black, and changing the pyrolysis temperature. By varying these parameters, the specific surface area, the hydrophilicity, and the roughness were adjusted, with the pyrolysis temperature playing a major role. When used as anodes at 0.2 V vs. Ag/AgCl sat. KCl in the BES, maximum current densities relative to the geometric surface area (jGSA) up to 5.8 A m−2 were achieved. Microbial community analysis of the biofilm shows the dominant presence of Geobacter spp. as the EAM. Benchmarking the performance of the anodes of this study with anodes using the same EAM demonstrates that porous SiOC anodes are a promising class of materials, as they show jGSA comparable to carbon‐based anodes.