Electrochemical activation of alkanes plays an enabling role for applications ranging from fuel cells to electro-production of materials and chemicals. Intermediate-temperature (>200 oC) electrochemical devices have improved diffusions, reaction kinetics, and feedstock flexibility. In this contribution, we present the electrochemical activation of alkanes using intermediate-temperature electrochemical devices. Our work is inspired by Duan et al. whose work showed that alkanes can be oxidized as fuel in protonic ceramic fuel cells1. We extend this concept and evaluate whether this electrochemical activation can activate longer-chain hydrocarbons to form industrial gases. We present a comparison of the electrochemical approach to pyrolysis, and in particular, its selectivity. Different electrocatalysts will be evaluated to test both electrochemical and thermal oxidation. Finally, we use small-molecule oxidation experiments to probe how the thermochemical reactions occur in parallel with the electrochemical conversion. We identify the products from these processes and propose the alkane activation mechanism. Duan, C.; Kee, R. J.; Zhu, H.; Karakaya, C.; Chen, Y.; Ricote, S.; Jarry, A.; Crumlin, E. J.; Hook, D.; Braun, R.; Sullivan, N. P.; O’Hayre, R., Highly durable, coking and sulfur tolerant, fuel-flexible protonic ceramic fuel cells. Nature 2018, 557 (7704), 217-222.

Hydrogen from water electrolysis is essential to energy and industrial decarbonization. Beyond being a carbon-neutral fuel to stabilize the intermittent nature of the renewable grid, hydrogen also plays a key role in manufacturing including ammonia and steel production. Intermediate-temperature water electrolysis (>200 °C) has several advantages. First, the thermodynamic requirement for water splitting decreases as temperature increases. Second, reaction kinetics are more facile at higher temperatures. We present water electrolysis using an intermediate-temperature solid acid electrolysis cells (SAECs), with CsH2PO4 (CDP) as an electrolyte. Inspired by Fujiwara et al., whose work demonstrated water electrolysis in SAEC1, we extend upon their work to understand the role of electrode materials on stability and efficiency. We analyze the microstructure of post-electrolysis SAFCs to understand the role of temperature and electrode composition on the degradation. We focus on the reaction kinetics of the oxygen evolution reaction (OER) on the anode and present the challenges that must be overcome by future materials. (1) Fujiwara, N.; Nagase, H.; Tada, S.; Kikuchi, R. Hydrogen Production by Steam Electrolysis in Solid Acid Electrolysis Cells. ChemSusChem 2021, 14 (1), 417–427. https://doi.org/10.1002/cssc.202002281.

The structural characteristics of supports, such as surface area and type of porosity, affect the deposition of electrocatalysts and greatly influence their electrochemical performance in fuel cells. In this work, we use a series of high surface area hierarchical porous carbons (HPCs) with defined mesoporosity as model supports to study the deposition mechanism of Pt nanoparticles. The resulting electrocatalysts are characterized by several analytical techniques, and their electrochemical performance is compared to a state-of-the-art, commercial Pt/C system. Despite the similar chemical composition and surface area of the supports, as well as similar amounts of Pt precursor used, the size of the deposited Pt nanoparticles varies, and it is inversely proportional to the mesopore size of the system. In addition, we show that an increase in the size of the catalyst particles can increase the specific activity of the oxygen reduction reaction. We also report on our efforts to improve the overall performance of the above electrocatalyst systems and show that increasing the electronic conductivity of the carbon support by the addition of highly conductive graphene sheets improves the overall performance of an alkaline fuel cell.