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In this work, we demonstrate a combined bioelectrochemical and inorganic catalytic system for resource recovery from wastewater. We designed a microbial peroxide producing cell (MPPC) for hydrogen peroxide (H 2 O 2 ) production and used this bioelectrochemically derived H 2 O 2 as a green oxidant for sulfoxidation, an industrial reaction used for chemical synthesis and oxidative desulfurization of transportation fuels. We operated an MPPC equipped with a gas diffusion electrode cathode for six months, achieving a peak current density above 1.4 mA cm −2 with 60% average acetate removal and 61% average anodic Coulombic efficiency. We evaluated several cathode buffers under batch and continuousflow conditions for solubility and pH compatibility with downstream catalytic systems. During 24-h batch tests, a phosphatebuffered MPPC achieved a maximum H 2 O 2 concentration of 4.6 g L −1 and a citric acid−phosphate-buffered MPPC obtained a moderate H 2 O 2 concentration (3.1 g L −1 ) at a low energy input (1.6 Wh g −1 H 2 O 2 ) and pH (10). The MPPC-derived H 2 O 2 was used directly as an oxidant for the catalytic sulfoxidation of 4-hydroxythioanisole over a solid niobium(V)−silica catalyst. We achieved 82% conversion of 50 mM 4-hydroxythioanisole to 4-(methylsulfinyl)phenol with 99% selectivity with a 0.5 mol % catalyst loading in 100 min in aqueous media. Our results demonstrate a new and versatile approach for valorization of wastewater through continuous production of H 2 O 2 and its subsequent use as a selective green oxidant in aqueous conditions for green chemistry applications.

Some catalytic oxide supports are more equal than others, with numerous variable properties ranging from crystal symmetry to surface chemistry and electronic structure. As a consequence, it is often very difficult to determine which of these act as the driver of performance changes observed in catalysis. In this work, we hold many of these variable properties constant with structurally similar LnScO3 (Ln = La, Sm, and Nd) nanoparticle supports with cuboidal shapes and a common Sc-rich surface termination. Using CO oxidation over supported Au nanoparticles as a probe reaction, we observe higher activation energy and a slower rate using NdScO3 as the support material. This change is found to correlate to the strength of CO2 binding to the support surface, identified by temperature-programmed desorption measurements. The change is due to differences in the 4f electrons of the lanthanide cations, the cations’ Lewis acidity, and the inductive effect they impose.

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