First-row transition metal carbonates catalyze the electrochemical oxygen evolution reaction: iron is master of them all.

In pursuing green hydrogen fuel, electrochemical water-splitting emerges as the optimal method. A critical challenge in advancing this process is identifying a cost-effective electrocatalyst for oxygen evolution on the anode. Recent research has demonstrated the efficacy of first-row transition metal carbonates as catalysts for various oxidation reactions. In this study, Earth-abundant first-row transition metal carbonates were electrodeposited onto nickel foam (NF) electrodes and evaluated for their performance in the oxygen evolution reaction. The investigation compares the activity of these carbonates on NF electrodes against bare NF electrodes. Notably, Fe2(CO3)3/NF exhibited superior oxygen evolution activity, characterized by low overpotential values, i.e. Iron is master of them all (R. Kipling, Cold Iron, Rewards and Fairies, Macmillan and Co. Ltd., 1910). Comprehensive catalytic stability and durability tests also indicate that these transition metal carbonates maintain stable activity, positioning them as durable and efficient electrocatalysts for the oxygen evolution reaction.

Interface-Driven Multifunctionality in Two-Dimensional TiO2 Nanosheet/Poly(Dimercaptothiadiazole-Triazine) Hybrid Resistive Random Access Memory Device.

Interface-driven multifunctional facets are gearing up in the field of science and technology. Here, we present the interface-activated resistive switching (RS), negative differential resistance, diode behavior, and ultraviolet (UV) light sensing in nanosheet-based hybrid devices. A hybrid device i.e., titanium dioxide nanosheet (TiO2-NS)/poly(dimercaptothiadiazole-triazine)[Poly(DMcT-CC)] is fabricated by spin coating Poly(DMcT-CC) polymer on hydrothermally as-grown TiO2-NS. The pristine devices of both materials show either small or no magnitude of RS, but the hybrid device shows highly enhanced RS of nearly four orders due to the formation of a p-n junction at the NS/polymer interface. The resistive random access memory feature appears to be more prominent in the hybrid device i.e., high and low current states are found to be stable in repetitive cycles since the interface acts as a trapping center for the carriers. The UV sensing ability of the hybrid device has been demonstrated by a threefold increment in a current at 60 mV. The impedance spectroscopy has been employed to show that the multifunctional features are directly associated to the NS/polymer interface, which deduce that the manipulation of such interfaces can pave the way for developing the hybrid structures.