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Acetic acid (AA), an important commodity chemical, is produced via methanol carbonylation, emitting one ton of CO₂ per ton of product. As a sustainable alternative, we report the electrochemical oxidation of bioethanol to selectively produce AA using a novel Pdsingle bondSn alloy catalyst with nanodendritic morphology supported on nickel foam (PdSn@NF). The catalyst was synthesized via electrodeposition, and the presence of ammonium chloride in the deposition bath was found to critically affect the Pd-to-Sn ratio and, consequently, the catalyst performance. The vital role of catalyst structure, surface composition, and morphology on the activity and selectivity of PdSn@NF towards the EOR was revealed by X-ray diffractometry, emission spectroscopy, and electron microscopy. Specifically, the nanodendritic morphology of the PdSn@NF resulted in the formation of highly active undercoordinated sites, while in situ Raman spectroscopy suggested that Sn helps mitigate CO poisoning – likely a result of a lowered d-band center. Due to the strong synergy between the structural and electronic properties of PdSn@NF, ~100 % faradaic efficiency (FE) to AA at 400 mA cm−2 was achieved with lab-grade ethanol (LGE) in an H-type cell. In continuous flow operation, the FE declined due to product accumulation on active sites; however, this was mitigated by employing current pulses to remove surface-bound products. An optimized pulsing protocol restored ~100 % FE of AA for LGE and achieved ~94 % FE with bioethanol at 400 mA cm−2 despite the presence of fermentation impurities. This study underscores the promise of PdSn@NF as a highly selective and industrially relevant electrocatalyst for sustainable AA production. 

A shift of the Li⁺ion hopping mechanism with temperature in solid-state lithium lanthanum titanate (LLTO) electrolytes was discovered usingab initiometadynamics simulations. 

Synthetic ammonia production by the Haber–Bosch process revolutionized agriculture by making relatively inexpensive nitrogen (N) fertilizer widely available and enabling a rise in global food production1,2. The Haber–Bosch process relies on fossil fuels (known as grey ammonia production) and emits more than 450 Mt of CO2 annually3. Green ammonia, which is produced using renewable energy, offers a pathway to decouple ammonia production from fossil fuels and reduce CO2 emissions. As a carbon-free fuel, green ammonia could partially replace fossil fuels to decarbonize hard-to-abate sectors such as maritime shipping4. However, the widespread use of green ammonia could have complex environmental and social consequences, as it threatens to add reactive N into the biosphere3 and could disrupt fertilizer markets. In this Comment, we identify opportunities, barriers and open questions related to green ammonia production and usage as a fertilizer and beyond. We then recommend research priorities to avoid unforeseen consequences through research, monitoring and adaptation in real time.