Electrochemical interfaces

The anthraquinone process is currently the predominant method for large-scale H₂O₂ production, but the reaction’s high energy consumption and hazardous waste generation spur the search for alternatives. Here, the authors investigate the two-electron oxygen reduction reactivities of metal-free non-porous, micro-, and mesoporous carbon catalysts to elucidate the impacts of porous structures, finding mesoporous structures show the highest H₂O₂ production selectivity.

The signal transducing interface between biosamples and detection devices plays a key role in translating electrochemical reactions into output signals and often governs detection limits and biocompatibility of the sensor. Here, the author reviews syntheses and properties of electrochemical interfaces of field-effect transistor-based biosensors.

All-solid-state lithium-ion batteries are promising energy storage devices owing to their safe use and high energy density, whereby understanding electrode and solid electrolyte interfaces is key for battery development. Here, the authors use spectroscopic ellipsometry, impedance measurements, as well as Monte Carlo simulations to elucidate the formation of charge depletion layers at the electrode/electrolyte interface.

The surface chemistries of electrode materials strongly influence their faradaic and non-faradaic properties. Here, the anode material Li₄Ti₅O₁₂ is probed in the presence of different electrolytes, and surface polarons are suggested to enable a Li ion equilibrium between the bulk and the electrolyte, explaining the role of defects for intercalative pseudocapacity and fast charging properties in this material.

The effect of the electric double layer with solid electrolytes remains hard to characterize. In this study, the authors show how to evaluate the electric double layer effect with various lithium solid electrolytes using a hydrogenated diamond-based transistor.

Lithium-ion batteries suffer from declining performance when the electrolyte decomposes. Now, low-dosage cryogenic transmission electron microscopy (cryo-TEM) visualizes how the common solid electrolyte interface component lithium carbonate decomposes and how additives stabilize the interface.

Biosourced and biodegradable organic electrode materials are investigated for environmentally benign energy storage, but their performance at higher current density is often poor. Here, the authors construct electrodes with quinone-based species from Sepia melanin and tannins on treated carbon paper and observe electrode capacitance as high as 1355 mF cm⁻² at current densities up to 10 A g⁻¹.